# GCN_circulars

GRB_name: GRB081209A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8664
SUBJECT: GRB 081209: Fermi GBM detection
DATE:    08/12/12 21:24:02 GMT
FROM:    Colleen A. Wilson at NASA/MSFC/NSSTC  <colleen.wilson@nasa.gov>

Colleen A. Wilson-Hodge (NASA/MSFC) and Valerie Connaughton (UAH)
report on behalf of the Fermi GBM Team:

"At 23:41:56.39 UT on 9 December 2008, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB 081209 (trigger 250558317 / 081209981).

The on-ground calculated location, using the GBM trigger data, is
RA = 45.3, DEC = 63.5 (J2000 degrees, equivalent to 02 h 20 m, 68 d 52'),
with an uncertainty of 4.9 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees). This location overlaps the IPN
arc reported in Golenetskii et al. 2008 (GCN Circular #8646).
 
The angle from the Fermi LAT boresight is 109 degrees.

The GBM light curve consists of a single peak with a duration (T90) of
about 0.4 s (8-1000 keV). The time-averaged spectrum from T0-0.110 s to
T0+0.210 s is best fit by a Band function with Epeak = 808 +/- 163 keV,
alpha = -0.5 +/- 0.1, and beta = -2.0 +/- 0.1. (chi squared 321.85 for
360 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(5.9 +/- 0.3)E-07 erg/cm^2. The 1-sec photon flux measured starting from
T0-0.110 s in the 8-1000 keV band is 7.8 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081207A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8665
SUBJECT: GRB 081207: Fermi GBM detection
DATE:    08/12/13 00:16:48 GMT
FROM:    Michael S. Briggs at UAH and MSFC  <michael.briggs@nasa.gov>

M. S. Briggs (UAH) and A.J. van der Horst (NASA/MSFC/ORAU) report
on behalf of the Fermi GBM Team:

"At 16:18:46.94 UT on 7 December 2008, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB 081207 (trigger 250359527 / 081207680).
The on-ground calculated location, using the GBM trigger data, is
RA = 119.2, DEC = +66.9 (J2000 degrees, equivalent to 7h57m, +66d54'),
with an uncertainty of 1.6 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT
boresight is 56 degrees.

The GBM light curve consists of one pulse with a duration (T90) of about
153 s (10-1000 keV). The time-averaged spectrum from T0+9.2s to T0+66.6s
is best fit by a Band function with Epeak = 639 +/- 42 keV,
alpha = -0.65 +/- 0.03, and beta = -2.41 +/- 0.17. The event fluence
(10-1000 keV) in this time interval is (1.06 +/- 0.2)E-4 erg/cm^2.

The spectral and timing analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081211B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8666
SUBJECT: Possible GRB 081211B - Swift-XRT analysis
DATE:    08/12/13 09:19:47 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page, P.A. Evans (U. Leicester) and S.T. Holland (CRESST/USRA/GSFC) 
report on behalf of the Swift-XRT team:

Swift-XRT performed a Target of Opportunity observation of the possible 
BAT Slew Survey (BATSS) burst GRB 081211B (Copete et al., GCN Circ. 8661), 
starting 81.6 ks after the slew in which it was detected, and found a 
single, uncatalogued X-ray source within the BATSS error circle.

Using 1878 s of XRT Photon Counting mode data and 4 UVOT images, we find 
an astrometrically corrected X-ray position (using the XRT-UVOT alignment 
and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 
168.2646, 53.8300 which is equivalent to:

RA (J2000):  11 13 3.49
Dec (J2000): +53 49 48.1

with an uncertainty of 2.0 arcsec (radius, 90% confidence).

During the initial observation (81.6-92 ks), the mean X-ray count rate was 
0.035 +/- 0.005 count s^-1. A second observation (126-133 ks) showed a 
count rate of 0.018 +/- 0.006. The source, therefore, appears to have 
faded, with a power-law index, alpha = 1.4 +0.8/-0.9. However, we cannot 
rule out a constant source at this time, so cannot categorically confirm 
this is an X-ray afterglow.

This is an official product of the Swift-XRT team.


GRB_name: GRB081210A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8667
SUBJECT: GRB 081210: optical observations
DATE:    08/12/14 17:44:38 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

V. Rumyantsev (CrAO), A. Pozanenko (IKI) on behalf of larger GRB follow up 
collaboration report:

We observed the error box of Swift GRB 081210 (Krimm  et al, GCN  8648) in R 
band on Dec. 10 between (UT)  22:31:15 -  23:05:19 with Shajn telescope of 
CrAO. Inside the enhanced XRT error box (Osborne et al. GCN 8650) we do not 
detect optical afterglow (Krimm   et al, GCN 8648). A photometry based on 
0787-0047183 USNO B1.0 star  (04:41:55.26 -11:14:39.0) assuming  R2=16.33 is 
following:

T0+    Filter,  Exp.,     UL
(h)             (s)       (3 sigma)

2.487  R        29x60     >20.0 


GRB_name: GRB081213A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8668
SUBJECT: GRB 081213: Fermi GBM detection
DATE:    08/12/15 16:00:47 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team: 

"At 04:09:41.64 UT on 13 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081213 (trigger 250834182 / 081213173).
The on-ground calculated location, using the GBM trigger data,
is RA = 25.5, Dec = -35.3 (J2000 degrees,
equivalent to 01h 42m, -35d 18'), with an uncertainty
of 12.5 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 51 degrees.

This short GRB consists of a single peak with a duration of about 50 ms.
Since the source is weak, the time-averaged spectrum is poorly constrained."


GRB_name: GRB081211B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8669
SUBJECT: Possible GRB 081211B: Swift/UVOT Upper Limits
DATE:    08/12/15 17:27:44 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) reports, on the behalf of the Swift
UVOT team:

       The Swift/UVOT observed the field of the possible BAT Slew
Survey burst GRB 081211B (Copete et al., GCN Circ. 8661) starting 81.7
ks after the start of the slew that this source was detected in.  We
find no new source, relative to the DSS, USNO-B1.0, or 2MASS, or a
variable source, inside the UVOT-enhanced XRT error circle (Page et
al. 2008, GCN Circ. 8666).  Preliminary 3-sigma upper limits for
detecting a source in the co-added images, using an aperture-corrected
2.5 arcsecond radius circular aperture, are

Filter   T_start   T_stop  Exp(s)      Mag
------------------------------------------
    v      81,651  132,774    2318    >21.4
    b      85,687  126,980    1770    >22.5
  uvm2    132,780  133,265     478    >20.8
  uvw2     87,513  128,664    1426    >21.8
  white    86,600  127,893    1770    >23.1
------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight corresponding to a
reddening of E_{B-V} = 0.01 mag (Schlegel et al., 1998, ApJS, 500,
525).  All photometry is on the UVOT photometry system described in
Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB081215A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8671
SUBJECT: GRB 081215A: Andromeda inside Fermi error box: MASTER observations
DATE:    08/12/15 19:27:12 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, 
D.Kuvshinov, P.Balanutsa
Sternberg Astronomical Institute, Moscow State University

A. Tlatov, A.V. Parhomenko Kislovodsk Solar Station of the Pulkovo Observatory

V.Krushinski, I.Zalognikh
Ural State University, Kourovka


S.Yazev, K.Ivanov
Irkutsk State University

One of the four  MASTER Very Wide Field Cameras located at Kislovodsk
(http://apollo.sai.msu.ru/, D=50 mm, 4x1000 square degrees, 35'' per pix)
has observed  Fermi  error box  (Trig Num 251059717) with 5s exposures during 
all night without time gap between images.
The M31 (ANdromeda) is inside Fermi error box.

The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB081215A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8673
SUBJECT: GRB 081215A: Gamma Repeater?
DATE:    08/12/15 20:32:18 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

V. Lipunov, E. Gorbovskoy,

If the GRB 081215A really connected with M31 (Gorbovskoy et al, GCN 
Circ 8671,  8672) it must be Soft Gamma Repeater or Andromeda X-ray 
binary source.

The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB081118A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8675
SUBJECT: GRB 081118: Zadko observations
DATE:    08/12/16 01:27:18 GMT
FROM:    David Coward at U of Western Aus.  <coward@physics.uwa.edu.au>

Subject: GRB 081118: Zadko observations
From: D.M Coward at UWA


D.M. Coward, T. Vaalsta, J. Zadko, A. Imerito, D. Blair, R. Burman,  
P. Lucas, S. Gordon, K. Frost, A. Fletcher
(University of Western Australia)
M. Todd, M. Zadnik (Curtin University)
M. Boer, A. Klotz (TAROT)


On 18 Nov, the Zadko Telescope team observed the XRT field of GRB  
081118 reported by P. Evans (GCN 8525) using the 1 meter Zadko  
Telescope (in very early commissioning mode). Imaging commenced  
approx 1.96 hr post burst trigger using an unfiltered integrating CCD  
video camera and continued over a period of 1 hr.
  The OA candidate reported by GCN 8529 is seen in a selected stack  
of 40 x 5 second exposures, though it is near the detection limit.
  We do not have absolute standard star photometric calibration.
Using nearby USNO-B1 stars we estimate the limiting magnitude of the  
OA to be in the range 20.9 +- 0.5.

This message is quotable in publications.

David Coward and Timo Vaalsta report on behalf of the UWA Zadko  
Telescope Team.


GRB_name: GRB081211B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8676
SUBJECT: GRB 081211B - possibly a short burst with extended emission
DATE:    08/12/16 18:19:57 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and 
and T. Cline, on behalf of the Konus-Wind team,

J. Cummings, S. Barthelmy, N. Gehrels, and H. Krimm, on behalf of
the Swift-BAT team,

On December 11, Konus-Wind detected in the waiting mode a short spike at 
06:12:58 UT, ~120 s before the BATSS GRB 081211B (Copete et al., GCN 
8661). The burst was seen as a single 2.9s-long spike in the G1 (20-70 
keV) and G2 (70-300 keV) bands. The BAT also detected this burst at 
06:12:55.1 UT as a weak single pulse that did not produce a significant 
on-board image. The BATSS position of GRB 081211B was 1.3% coded in the 
BAT at the time of this burst.
The measured propagation time delay from Swift to Wind as well as the 
K-W ecliptic latitude response for a short spike are consistent with the 
position of GRB 081211B. Hence, taking in account that the BATSS 
GRB081211B light curve shape suggests that it is possibly the tail end 
of the prompt emission of a burst (Copete et al., GCN 8661), we believe 
that the short spike detected by Konus-Wind and BAT is the main burst 
(likely short), followed by a long tail (extended emission) seen as the 
BATSS GRB081211B.
There is a hint of the extended emission in the K-W G1 and G2 bands.

The K-W light curve of this GRB is available at 
http://www.ioffe.ru/LEA/GRBs/GRB081211B/


GRB_name: GRB081216A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8677
SUBJECT: IPN localization of short hard GRB 081216
DATE:    08/12/17 16:39:34 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, T. 
Cline on behalf of the Konus-Wind team,

K. Yamaoka, M. Ohno, Y. Fukazawa, T. Takahashi, M. Tashiro, Y. Terada,
T. Murakami, and K. Makishima on behalf of the Suzaku-WAM team,

A. von Kienlin, G. Lichti, and A. Rau, and K. Hurley on behalf of the
INTEGRAL SPI-ACS GRB team, report:

Suzaku-WAM, INTEGRAL-SPI-ACS, and Konus-Wind observed the short-duration 
hard spectrum GRB 081216 at about 12:44:00 UT (corresponds to the 
Fermi/GBM trigger 251124240). The burst light curve shows a single pulse 
with a duration of ~0.2 sec.

We have triangulated it to the following, 3-sigma
error box:
-----------------------------------------------
      RA(2000), deg            Dec(2000), deg
-----------------------------------------------
Center:
  130.205 (08h 40m 49s)   +11.816 (+11d 48' 57")
Corners:
  129.100 (08h 36m 24s)   + 8.470 (+08d 28' 11")
  129.552 (08h 38m 12s)   + 8.548 (+08d 32' 53")
  131.144 (08h 44m 35s)   +15.131 (+15d 07' 52")
  130.699 (08h 42m 48s)   +15.056 (+15d 03' 20")
-----------------------------------------------

The error box area is 2.762 sq. deg.

Analysis of the Konus-Wind data yields
a burst fluence of ~5x10^-6 erg/cm2 (in the 20 keV - 7 MeV range),
and an Epeak of the time-integrated spectrum of ~1.5 MeV.
Since the incident angle on the K-W detector was >90 deg,
a detailed reliable spectral analysis of the K-W data can not be performed.

The results of spectral analysis of the Suzaku-WAM data will be reported 
later.

The K-W light curve of this GRB and IPN triangulation map is
available at http://www.ioffe.ru/LEA/GRBs/GRB081216_T45844/


GRB_name: GRB081215A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8678
SUBJECT: GRB 081215A: Fermi GBM detection
DATE:    08/12/17 22:42:55 GMT
FROM:    Rob Preece at UAH  <Rob.Preece@nasa.gov>

Robert Preece (UAH) reports on behalf of the Fermi GBM Team:

"At 18:48:36.85 UT on 15 December 2008, the Fermi Gamma-Ray Burst  
Monitor
triggered and located GRB 081215 (trigger 251059717 / 081215784).

The on-ground calculated location, using the GBM trigger
data, is RA = 135.0, DEC = +53.8 (J2000 degrees,
equivalent to 09 h 00 m 00.00, 53 d 48 '), with an uncertainty
of 1.0 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 86 degrees.

The on-board GBM Flight Software localization for this very bright
burst, as reported in the GCN Notices, was consistent
with a position on the Earth's surface, likely due to a large scattered
flux from the Earth. This resulted in an autonomous and erroneous
"100%  Below horizon" classification for this event which prevented an
automated ground localization from being sent through the GCN notice
system.

The GBM light curve consists of a very hard narrow pulse on
top of a broader emission episode,
with a duration (T90) of about 7.7 s (8-1000 keV).
The time-averaged spectrum from T0-1.79 s to T0+13.57 s is
best fit by a Band function with Epeak = 304 +/- 11 keV,
alpha = -0.585 +/- 0.022, and beta = -2.066 +/- 0.038.

The event fluence (8-1000 keV) in this time interval is
(3.54 +/- 0.05)E-6 erg/cm^2. The 1-sec photon flux measured
starting from T0+1.28 s in the 8-1000 keV band
is 68.9 +/- 1.0 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081215A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8679
SUBJECT: GRB 081215A: Fermi GBM detection (correction to event fluence)
DATE:    08/12/18 17:05:04 GMT
FROM:    Rob Preece at UAH  <Rob.Preece@nasa.gov>

Robert Preece (UAH) reports on behalf of the Fermi GBM Team:

"The correct event fluence for the GRB detection reported
in Circular Number 8678 should be:
(5.44 +/- 0.07)E-5 erg/cm^2 in the energy interval 8-1000 kev
for times -T0-1.79 s to T0+13.57 s. Thanks to Alexander Kann
at TLS Tautenburg for spotting the error."


GRB_name: GRB081216A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8680
SUBJECT: GRB 081216 : Fermi GBM observation
DATE:    08/12/18 18:07:45 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

Sheila McBreen (UCD/MPE) and Andreas von Kienlin (MPE)
report on behalf of the Fermi GBM Team:

"At 12:43:59.99 UT on 16 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081216 (trigger 251124240 / 081216531).

The on-ground calculated location, using the GBM trigger
data, is RA = 123.2, DEC = +13.7 (J2000 degrees,
equivalent to 08 h 13 m, +13 d 42'), with an uncertainty
of 7 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from  the Fermi LAT boresight is 95 degrees.

This burst was also independently detected by
Suzaku-WAM, INTEGRAL-SPI-ACS, and Konus-Wind (Golenetskii et al., GCN 8677)
and the GBM localisation is consistent with the IPN localisation.

This short, hard burst consists of 2 pulses
with a duration (T90) of about 0.96 s (10-1000 keV). The second and
main pulse starts at T0+0.5 s and was detected by Golenetskii et al.
The time-averaged spectrum from T0-0.13 s to T0+0.83 s is
adequately fit by  a Band function with Epeak = 1235 +/- 264 keV,
alpha = -0.70 +/-0.09, and beta = -2.17+/-0.21
(chi squared 358 for 356 d.o.f.).

The event fluence (10-1000 keV) in this time interval is
(3.6 +/- 0.1)E-06 erg/cm^2. The 32 ms peak photon flux measured from
T0+0.62 s in the 10-1000 keV band is 55 +/- 3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081216A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8681
SUBJECT: GRB 081216: Suzaku WAM observation of the prompt emission
DATE:    08/12/18 18:26:18 GMT
FROM:    Kazutaka Yamaoka at Aoyama Gakuin U  <yamaoka@phys.aoyama.ac.jp>

A. Endo, M. Tashiro, Y. Terada, Y. Urata, K. Onda,
N. Kodaka, K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.),
T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), S. Sugita,
K. Yamaoka (Aoyama Gakuin U.), M. Ohno, M. Kokubun, M. Suzuki,
T. Takahashi (ISAS/JAXA), Y.E. Nakagawa, T. Tamagawa (RIKEN),
Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira 
(Hiroshima U.), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, 
N. Ohmori, K. Kono, H. Hayashi (Univ. of Miyazaki), S. Hong (Nihon U.), 
on behalf of the Suzaku WAM team, report:

The IPN-localized short hard GRB 081216 (Golenetskii et al., GCN 8677; 
Fermi/GBM trigger #251124240; McBreen et al., GCN 8680) triggered the 
Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 
50 keV - 5 MeV at 12:44:00.303 UT (=T0).

The observed light curve shows a single peak starting at
T0+0.2s, ending at T0+0.4s with a duration (T90) of about 0.2
seconds. The fluence in 100 - 1000 keV was (2.0 +/- 0.2) x 10^-6 erg/cm^2.
The 1-s peak flux measured from T0 s was 3.7 (+0.2, -0.4) photons/cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0 s to T0+0.5 s is well fitted by a power-law with exponential
cutoff model:
dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha = 0.51 (+0.24, -0.28), and
Epeak = 1090 (+203, -167) keV (chi^2/d.o.f. = 26.5/24).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB081215B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8682
SUBJECT: GRB 081215B: Fermi GBM detection
DATE:    08/12/19 15:31:23 GMT
FROM:    Vandiver Chaplin at UAH/Fermi-GBM  <chapliv@email.uah.edu>

V. Chaplin (UAH), A.J. van der Horst (NASA/MSFC/ORAU)
and R. Preece (UAH) report on behalf of the Fermi GBM Team:

"At 21:06:53.03 UT on 15 December 2008, the Fermi Gamma-Ray Burst  
Monitor
triggered and located GRB 081215B (trigger 251068014 / 081215.880).
The on-ground calculated location, using the GBM trigger
data, is RA = 244.8, DEC = -45.3 (J2000 degrees,
equivalent to 16h19m, -45d20'), with a statistical uncertainty of 5.9  
degrees
(radius, 1-sigma containment, statistical only; there is additionally
a systematic error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 112 degrees.

The GBM light curve shows/consists of two peaks, each with a duration  
of ~10 seconds, at T0
and ~T0+80 seconds, with little emission in between.
The time-averaged spectrum from T0-1.3 s to T0+7.9 s is
well fit by a power law function with an exponential
high energy cutoff. The power law index is -0.14 +/- 0.26 and
the cutoff energy, parameterized as Epeak, is 139 +/- 14 keV.
The event fluence (50-300 keV) in this time interval is
(2.8 +/- 0.5)E-06 erg/cm^2.

The spectral and temporal analysis results presented above are  
preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081211B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8683
SUBJECT: GRB 081211B: Further Swift-XRT analysis
DATE:    08/12/19 16:21:47 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page, J.P. Osborne (U. Leicester) and S.T. Holland (CRESST/USRA/GSFC) 
report on behalf of the Swift-XRT team:

The possible BAT Slew Survey burst GRB 081211B has been observed again by 
Swift, 8 days after it was first located. The source mentioned by Page et 
al. in GCN Circ. 8666 is not detected in 2.3 ks of XRT data, with an upper 
limit of 4.3x10^-3 count s^-1 (equivalent to a 0.3-10 keV observed flux of 
~1.6x10^-13 erg cm^-2 s^-1). The decay slope is 1.6 +0.9/-0.6, 
incorporating the limit placed by this non-detection. We therefore confirm 
that the source has faded.

This is an official product of the Swift-XRT team.


GRB_name: GRB081215A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8684
SUBJECT: GRB081215A: Fermi-LAT observations
DATE:    08/12/19 17:34:59 GMT
FROM:    Julie McEnery at UMBC/GSFC  <mcenery@milkyway.gsfc.nasa.gov>

Julie McEnery (NASA/GSFC) reports on behalf of the Fermi LAT team

We report a detection by the Fermi Large Area Telescope (LAT) of 
emission from GRB081215A (Preece et al, GCN8678).

This burst was at an angle of 86 degrees to the LAT boresight, which 
means that neither directional nor energy information can be obtained 
with the standard analysis procedures.

Using a non-standard data selection, over 100 counts above background 
were detected within a 0.5 s interval in coincidence with the main GBM 
peak. The significance of this excess was greater than 8 sigma. A 
preliminary study of the instrument performance at such a large 
inclination suggests that these events are likely to be low energy 
gamma-rays, with energies less than 200 MeV.

Further analysis is ongoing.

The Fermi LAT point of contact for this burst is Julie McEnery 
(julie.mcenery@nasa.gov).

The Fermi LAT is a pair conversion telescope designed to cover the 
energy band from 20 MeV to greater than 300 GeV. It is the product of an 
international collaboration between NASA and DOE in the U.S. and many 
scientific institutions across France, Italy, Japan and Sweden.
This message can be cited.


GRB_name: GRB081203A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8685
SUBJECT: Modification of Swift/UVOT response to bright GRBs
DATE:    08/12/19 21:10:47 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W. Landsman (GSFC), P. Kuin (MSSL), F. Marshall (GSFC), M. Page (MSSL), 
P. Roming (PSU), N. Gehrels (GSFC) report on behalf of the Swift/UVOT team

The Swift/UVOT has modified its automated response to GRBs with a BAT 
trigger rate larger than 100 cps.   For these bright GRBs, a 50s UV 
grism exposure is now inserted following the first 150s finding chart in 
the white filter.      Roughly half of all Swift GRBs are sufficiently 
bright to trigger the use of the grism.

The UVOT grism covers the spectral range 1700 - 5500 A, and  can provide 
useful spectra for GRBs brighter than about V~13.     Further details 
are available in Kuin et al. (2008, astro-ph 0812/2943 ) who report 
their analysis of the UVOT grism spectrum of GRB081203A.

The grism zero-order spectrum in the 50s exposure can provide photometry 
for sources brighter than B-18.    The zero-order spectrum includes 
visible light and its brightness roughly  correlates with Johnson B 
magnitude, with a scatter of about 0.23 mag.


GRB_name: GRB081217A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8686
SUBJECT: GRB 081217: Fermi GBM detection
DATE:    08/12/19 22:33:44 GMT
FROM:    Colleen A. Wilson at NASA/MSFC/NSSTC  <colleen.wilson@nasa.gov>

Colleen A. Wilson-Hodge (NASA/MSFC)
reports on behalf of the Fermi GBM Team:

"At 23:34:49.01 UT on 17 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081217 (trigger 251249690 / 081217983).

The on-ground calculated location, using the GBM trigger data, is
RA = 116.7, DEC = +26.7 (J2000 degrees, equivalent to 07 h 47 m, 26 d 44'),
with an uncertainty of 2.0 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 54 degrees.

The GBM light curve consists of a broad structured peak with a duration
(T90) of about 39 s (8-1000 keV). The time-averaged spectrum from T0 to
T0+18.432 s is adequately fit by a Band function with
Epeak = 167 +/- 11 keV, alpha = -0.61 +/- 0.09, and beta = -2.7 +/- 0.6.
 
The event fluence (8-1000 keV) in this time interval is
(1.0 +/- 0.07)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0 in the 8-1000 keV band is 4.0 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081221A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8687
SUBJECT: GRB 081221: Swift detection of a burst
DATE:    08/12/21 16:42:05 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

E. A. Hoversten (PSU), W. H. Baumgartner (GSFC/UMBC),
D. N. Burrows (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC),
J. A. Kennea (PSU), V. Mangano (INAF-IASFPA),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
P. T. O'Brien (U Leicester), D. M. Palmer (LANL),
J. L. Racusin (PSU), P. Romano (INAF-IASFPA),
B. A. Rowlinson (U Leicester), M. C. Stroh (PSU),
G. Tagliaferri (INAF-OAB), T. N. Ukwatta (GSFC/GWU) and
L. Vetere (PSU) report on behalf of the Swift Team:

At 16:21:11 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 081221 (trigger=337889).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 15.805, -24.526 which is 
   RA(J2000) = 01h 03m 13s
   Dec(J2000) = -24d 31' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed two peaks, at 
T+0 to T+10 seconds and a much larger one at T+15 to T+40 seconds.  
The peak count rate was ~20000 counts/sec (15-350 keV), at 22 sec 
after the trigger. 

The XRT began observing the field at 16:22:20.2 UT, 68.4 seconds after
the BAT trigger. XRT found a bright, fading, uncatalogued X-ray source located
at RA, Dec 15.7934, -24.5484 which is equivalent to:
   RA(J2000)  = 01h 03m 10.41s
   Dec(J2000) = -24d 32' 54.2"
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This
location is 89 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

The initial flux in the 0.1 s image was 7.36e-08 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White  
filter starting 78 seconds after the BAT trigger, and a finding  
chart exposure of 250 seconds with the u filter starting 290 seconds 
 after the trigger. No credible afterglow candidate has been found in 
 the initial data products. The 2.7'x2.7' sub-image covers 100% of  
the XRT error circle. The 3-sigma upper limit at the XRT position is 
19.9  mag in White, 19.8 mag in u. No correction has been made for 
the expected extinction  corresponding to E(B-V) of 0.02. 

We note that this burst is coincident with a Fermi GBM burst (trigger 251569273). 

Burst Advocate for this burst is E. A. Hoversten (hoversten AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB081221A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8688
SUBJECT: GRB 081221: NOT observations
DATE:    08/12/21 20:13:16 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@astro.ku.dk>

Daniele Malesani, Johan P. U. Fynbo (DARK/NBI), Eric Stempels (Univ. St. 
Andrews), and Tapio Pursimo (NOT), report on behalf of a larger 
collaboration:

We observed the field of GRB 081221 (Hoversten et al., GCN 8687) with 
the NOT equipped with ALFOSC. R-band imaging was carried out (12 min 
exposure) with mean time Dec 21.81 UT (3.14 hr after the GRB). Inside 
the XRT error circle (Hoversten et al., GCN 8687), we detect no source 
down to a limiting magnitude R ~ 23. Further imaging is ongoing.

We note the presence of two faint sources just outside the XRT error 
circle, at approximate coordinates (J2000):

1: RA = 01:03:10.26, Dec = -24:32:47.4, R ~ 22.3
2: RA = 01:03:10.10, Dec = -24:32:58.6, R ~ 23.0

We acknowledge excellent support from the NOT staff.


GRB_name: GRB081221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8689
SUBJECT: GRB 081221: further NOT observations
DATE:    08/12/21 22:12:49 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@astro.ku.dk>

Daniele Malesani, Johan P. U. Fynbo (DARK/NBI), Tapio Pursimo (NOT), and 
Eric Stempels (Univ. St. Andrews) report on behalf of a larger 
collaboration:

Further to what reported in GCN 8688, we observed the field of GRB 
081221 (Hoversten et al., GCN 8687) in the I and z filters with the NOT 
equipped with ALFOSC. Exposure times were 18 and 16 min, respectively, 
with mean times Dec 21.844 and Dec 21.863 UT (3.89 and 4.37 hr after the 
GRB, respectively).

Inside the XRT error circle reported by Hoversten et al. (GCN 8687), we 
do not detect any source in either filters. The limiting magnitude is I 
~ 23 assuming I = 17.65 for the USNO star at RA = 01:03:09.59, Dec = 
-24:32:45.0.

We encourage deeper searches of the optical/NIR counterpart of this 
event, which had a bright gamma- and X-ray prompt emission.


GRB_name: GRB081221A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8690
SUBJECT: GRB 081221: Enhanced Swift-XRT position
DATE:    08/12/22 03:22:16 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 4345 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 081221, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 15.7925, -24.5481 which is equivalent
to:

RA (J2000): 01h 03m 10.20s
Dec (J2000): -24d 32' 53.1"

with an uncertainty of 1.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB081222A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8691
SUBJECT: GRB 081222: Swift detection of a burst with a bright optical afterglow
DATE:    08/12/22 05:28:23 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

D. Grupe (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), C. B. Markwardt (CRESST/GSFC/UMD),
D. M. Palmer (LANL), J. L. Racusin (PSU), M. Stamatikos (NASA/ORAU)
and M. C. Stroh (PSU) report on behalf of the Swift Team:

At 04:53:59 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 081222 (trigger=337914).  Swift slewed immediately to the 
burst.  The BAT on-board calculated location is 
RA, Dec 22.751, -34.128 which is 
   RA(J2000) = 01h 31m 00s
   Dec(J2000) = -34d 07' 41"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multipeaked
structure with a duration of about 20 sec.  The peak count rate
was ~10000 counts/sec (15-350 keV), at 3 sec after the trigger. 

The XRT began observing the field at 04:54:51.7 UT, 51.8 seconds after
the BAT trigger. Using promptly downlinked data we find a bright, fading,
uncatalogued X-ray source located at RA, Dec 22.74067, -34.09556 which
is equivalent to:
   RA(J2000)  = 01h 30m 57.76s
   Dec(J2000) = -34d 05' 44.0"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 120 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
2.24e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 3.91e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 60 seconds after the BAT trigger. There is a
candidate afterglow in  the rapidly available 2.7'x2.7' sub-image
consistent with the XRT candidate.  A precise location and magnitude
estimate are not available at this time. 

This burst is consistent with the Fermi GBM burst   Trigger 251614441. 

Burst Advocate for this burst is D. Grupe (grupe AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB081222A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8692
SUBJECT: GRB081222: REM candidate afterglow
DATE:    08/12/22 05:30:11 GMT
FROM:    Stefano Covino at Brera Astronomical Observatory  <stefano.covino@gmail.com>

S. Covino, P. D'Avanzo, L.A. Antonelli, D. Malesani, D. Fugazza, L.  
Calzoletti,  S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini,   
V. D'Elia,  F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C.  
Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A.  
Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella,   
G. Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, F.  
Vitali report on behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed  
automatically the field of the GRB 081222 (Grupe et al. GCN8691)  
starting about 28s after the burst.  We detect a bright object in  
our  first H-band image inside the XRT error box at the following  
coordinates (J2000):

R.A. = 01:30:57.59
Dec = -34:05:41.7

with an uncertainty of about 1.0". The object is approximately H~11.1  
at about 1min after the burst and faded rapidly during the next  
observations.

Further observations are in progress


GRB_name: GRB081222A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8693
SUBJECT: GRB 081222: GROND Detection of the Optical/NIR Afterglow
DATE:    08/12/22 08:42:04 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

A. Updike (Clemson University), P. Afonso, C. Clemens, and J. Greiner (all
MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 081222 (Swift trigger 337914, Grupe et al.,
GCN #8691) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla
Observatory (Chile).

Observations started at 05:26 UT on Dec 22, 2008, 32 min after the GRB
trigger. They were performed at an average seeing of 1.0" and at high
airmass.

We detect the source within the Swift-XRT error circle reported by
Grupe et al. (GCN #8691) and Covino et al. (GCN #8692) at

RA (J2000) = 01h 30m 57.56s
DEC (J2000) = -34d 05' 41.5''

with an uncertainty of 0.5".

We obtained 8 min of total exposures in g'r'i'z'JHK.  Preliminary
magnitudes (calibrated against field stars in the USNO B1.0 and 2MASS
catalogs), exposure length (in seconds, NIR bands co-added), and midtimes
are as follows.

BAND     MAGNITUDE        EXP   MIDTIME (UT)
--------------------------------------------
g'      19.08 +/- 0.01    115    05:27:13
i'      18.04 +/- 0.01    115    05:27:13
z'      18.24 +/- 0.01    115    05:27:13
J       16.12 +/- 0.03    480    05:29:18
H       15.45 +/- 0.02    480    05:29:18
K       14.92 +/- 0.03    480    05:29:18


Tracking problems made data reduction difficult, especially in the r'
band, in which we detect the object but could not properly calibrate the
field.  The object is seen in g' band, implying a redshift smaller than
3.5.  No correction has been made for galactic extinction.


GRB_name: GRB081221A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8694
SUBJECT: Konus-Wind observation of GRB 081221
DATE:    08/12/22 11:05:55 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin,
D. Frederiks, P. Oleynik, D. Svinkin, M. Ulanov,
and T. Cline, on behalf of the Konus-Wind team report:

The long GRB 081221 (Hoversten et al., GCN 8687)
triggered Konus-Wind at T0=58874.915 s UT (16:21:14.915).

The burst light curve shows two multipeaked pulses with a total
duration of ~40 s.

As observed by Konus-Wind the burst
had a fluence of (2.28 +/- 0.07)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+19.824 s
of (1.75 +/- 0.16)x10^-6 erg/cm2/s
(both in the 20 keV - 1 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+39.424 s) can be fitted (in the 20 keV-1 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.91(-0.14, +0.15),
and Ep = (83 +/- 4) keV (chi2 = 67.4/51 dof).
Fitting by GRB (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy
photon index: beta < -3.48 (chi2 = 67.4/50 dof).

Thus, it is a bright and soft GRB.

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB081221_T58874/


GRB_name: GRB081203A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8695
SUBJECT: GRB081203A: BTA observation
DATE:    08/12/22 12:38:47 GMT
FROM:    Vladimir Sokolov at SAO RAS  <sokolov@sao.ru>

T. Fatkhullin, A. Moskvitin (SAO RAS, Russia), A. Posanenko (IKI RAS, 
Russia), E. Sonbas (SAO RAS,University of Cukurova, Turkey ),
A. Volnova (SAI MSU), V. Rumyantsev (CrAO), V. Kouprianov (GAO RAS),
V. Sokolov (SAO RAS) and A.J. Castro-Tirado ((IAA-CSIC Granada, Spain)
on behalf of a larger collaboration report:

We observed the field of the GRB081203A (A. M. Parsons et al., GCN #8595) 
in the Rc-band with the 6-m telescope of the SAO RAS in Caucasus. In total 15
3-min exposures were obtained starting from 01:42 7 Dec. 2008 UT (T-T_0 =
3.49 days).  We clearly detected an object at the position of the UVOT
optical transient (M. De Pasquale and A. Parsons, GCN #8603).
Calibration based on the SDSS stars yields the brightness of the OT as
R = 23.94 +/- 0.13 (errors are statistical only). At the 3.2 +/- 0.2 
arcsec to the South-West from the OT position we also detect an extended
object with R = 22.74 +/- 0.07. For redshift of z=2.05 (N.P.M Kuin et al,
astro-ph/0812.2943) it corresponds to ~26 kpc in projection (H0=71,
Omega_M=0.3, Omega_L=0.7). It is unlikely that this object is a host 
galaxy of the GRB081203A but redshift measurements are needed for certainty. 
Further observations are planned.

Our finding chart can be dowloaded from
ftp://ftp.sao.ru/pub/grb/GRB081203A/GRB081203A_OT.jpg

This message can be cited


GRB_name: GRB081222A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8696
SUBJECT: GRB081222: Swift/UVOT detection of an optical afterglow
DATE:    08/12/22 12:52:27 GMT
FROM:    Alice Breeveld at MSSL-UCL  <aab@mssl.ucl.ac.uk>

A.A. Breeveld (MSSL/UCL) and D. Grupe (PSU) report on behalf of the  
Swift UVOT team:

The Swift/UVOT started settled observations of the burst GRB081222  
(Grupe et al. GCN Circ. 8691) with the finding chart exposure in  
white, 60s after the BAT trigger. The afterglow is detected in the  
white and u filters at:
01h 30m 57.59s  -34d 05' 41.49" with a 0.5" 90% confidence limit.
This position is consistent with the XRT (Grupe et al. GCN Circ.  
8691), REM (Covino et al. GCN Circ. 8692) and GROND (Updike et al. GCN  
Circ. 8693) positions. The two white exposures show that the afterglow  
is fading with an estimated temporal slope of alpha = 0.85. The  
initial UVOT magnitudes are as follows:
Filter   Tstart(s)   Tstop(s)   Exp(s)   Magnitude
white   60            210           147.4     14.84+/-0.02
white   873          1023         147.4     17.36+/-0.03
u          272           522           245.8     16.32+/-0.03
The values quoted above are in the UVOT photometric system (Poole et  
al. 2008, MNRAS, 383, 627) and are not corrected for the expected  
Galactic extinction corresponding to a reddening of E(B-V)=0.021 mag  
in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB081222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8697
SUBJECT: GRB081222, optical observation
DATE:    08/12/22 13:43:55 GMT
FROM:    Norisuke Ohmori at Miyazaki U  <ohmori@astro.miyazaki-u.ac.jp>

E.Sonoda, H.Tanaka, R.Hara, N.Ohmori, K.Kono, H.hayasi, 
A.Daikyuji, K.Noda, Y.Nisioka, M.Yamauchi
(University of Miyazaki)


 We have observed the field covering the error circle of
GRB081222 (Swift trigger 337914, Grupe et al., GCN 8691) 
with the unfiltered CCD camera on the 30-cm telescope 
at University of Miyazaki.
The observation was started 08:41:19 UT, about 3.78 hr
after the Swift trigger time.
We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog,
the upper limits are as follows:
--------------------------------------------------------------
Start(UT)   End(UT)    Num. of frames    Limit (mag.)
--------------------------------------------------------------
10:36:04    10:36:19          1            ~16
10:36:04    10:49:52         12            ~17
---------------------------------------------------------------


GRB_name: GRB081221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8698
SUBJECT: GRB 081221: Gemini-N nIR imaging
DATE:    08/12/22 13:49:28 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick),
K. Wiersema (U. Leicester), A. S. Fruchter, J. Graham (STScI)
report:

We observed the field of GRB 081221 with Gemini-N/NIRI, starting
22 Dec 2008 04:20UT, approximately 12 hours post burst.

Our preliminary analysis reveals a faint point source in the enhanced
XRT error circle (GCN 8690) with magnitude K~20.1 at position:

01:03:10.19
-24:32:52.2

relative to three 2MASS stars in the field.  The source is also
marginally detected in J and H.

We suggest this is most likely the afterglow of GRB 081221, but that
its faintness and red colour (H-K>~2) argue for a dusty sight-line
rather than a high redshift as the explanation for the absence of an
optical detection (GCN 8688 and GCN 8689).

Further analysis is ongoing.

We thank Ricardo Schiavon (Gemini) for his assistance in obtaining
these observations.


GRB_name: GRB081222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8699
SUBJECT: GRB 081222: Faulkes Telescope South observations
DATE:    08/12/22 13:51:17 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

A. Melandri (Liverpool JMU), C. Guidorzi (U. Ferrara), D. Carter 
(Liverpool JMU)
report on behalf of a larger collaboration:

On 2008 December 22 (10:17:46 UT) we began observing the field of GRB 081222
(Grupe et al. GCN Circ. 8691) with the Faulkes Telescope South.
Observations consisted of two sequences of 6x300s exposures acquired
using the SDSS-i and SDSS-r filters, respectively.

We clearly detect the optical afterglow reported by REM (Covino et al.
GCN Circ. 8692) and GROND (Updike et al. GCN Circ. 8693), with the following
magnitudes:

Telescope   Filter  T_mid[hr]   Exposure[s]      Mag
--------------------------------------------------------------
FTS          SDSS-i    5.47        2x300        20.45 +/- 0.25
FTS          SDSS-r    6.01        2x300        21.34 +/- 0.30
--------------------------------------------------------------

The calibration was performed using the R2 and I magnitudes of several
USNOB-1 catalogue field objects. Uncertainties include the different
zero points of the USNOB-1 stars. Compared with the value reported by GROND
(Updike et al. GCN Circ. 8693), we estimate a power-law index between the
two epochs of about 1.1 .


GRB_name: GRB081221A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8700
SUBJECT: GRB 081221: pseudo-redshift (pz=0.7) from the spectral parameters  of the prompt emission
DATE:    08/12/22 14:02:52 GMT
FROM:    Jean-Luc Atteia at Lab d Astrophys.,OMP,Toulouse  <atteia@ast.obs-mip.fr>

A. Pelangeon and J-L. Atteia (LATT-OMP) report:

We have used the spectral parameters of GRB 081221 provided
by Golenetskii et al. (GCN Circ. 8694) to compute the spectral
pseudo-redshift** of this burst detected by Swift-BAT (Hoversten
et al. GCNC 8687).

We find a pseudo-redshift pz = 0.7 +/- 0.1

** http://cosmos.ast.obs-mip.fr/projet/index.html


GRB_name: GRB081221A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8701
SUBJECT: GRB 081221: Swift-XRT Refined Analysis
DATE:    08/12/22 14:26:07 GMT
FROM:    Michael Stroh at PSU/Swift  <stroh@astroh.org>

M.C. Stroh and E. A. Hoversten (PSU) report on behalf of the Swift-XRT  
team:

We have analyzed the first seven orbits of XRT data from GRB 081221  
(Hoversten et al., GCN 8687) beginning 73s after the trigger. The  
Swift-XRT data consists of 803s in Windowed Timing (WT) mode and 5.9ks  
in Photon Counting (PC) mode. The enhanced XRT position for this burst  
was reported by Evans et al. (GCN Circ. 8690).

The X-ray light curve begins with count rates near 10^3 cts/s and has  
an early flare reaching 1130 cts/s at T+103s. Following the flare, the  
light curve can be modeled with a double broken power-law with initial  
decay rate of 5.48 +/- 0.08, initial break time at T+207s, second  
decay rate of 0.68 +/- 0.20, second break time at T+896s, and a final  
decay rate of 1.35 +/- 0.04. If the light curve follows the same  
decline, we predict count rates at T+24hr and T+48hr to be 1.6e-2 and  
6.4e-3 respectively.

The time-averaged WT spectrum can be fit with an absorbed power law  
with photon index Gamma = 1.994 (+/-0.014) and nH of 3.24 (+/- 0.05)  
e21 cm^-2 which is in excess of the Galactic value of 2.03e20 cm^-2  
(Kalberla et al. 2005). The absorbed (unabsorbed) 0.3-10.0 keV flux is  
2.44 (3.86) e-9 ergs/cm^2/s.

The time-averaged PC spectrum can be fit with an absorbed power law  
with photon index Gamma = 2.37 (+/-0.15) and nH of 3.5 (+/-0.5) e21  
cm^-2. The absorbed (unabsorbed) 0.3-10.0 keV flux is 1.04 (2.17) e-11  
ergs/cm^2/s.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB081215A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8702
SUBJECT: IPN triangulation of bright GRB 081215A
DATE:    08/12/22 14:41:25 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, T. 
Cline, and K. Hurley on behalf of the Konus-Wind team,

M. Marisaldi, F. Fuschino, I. Donnarumma, E. Del Monte and M. Feroci on
behalf of the AGILE Team,

J. Cummings, S. Barthelmy, N. Gehrels, and H. Krimm, on behalf of
the Swift-BAT team, report:

AGILE-MCAL and Konus-Wind observed the very bright GRB 081215A at about 
18:48:38 UT (corresponds to the Fermi/GBM
trigger 251059717 / 081215784: Preece, GCN 8678, 8679). The burst was 
outside the coded field of view of the SuperAGILE. The burst light curve 
shows a multipeaked structure with a total duration of ~10 sec.
The Swift-BAT saw nothing at this time. Hence, taking in account the 
high intensity of this GRB, that means the source of the burst was below 
the horizon for Swift.

Triangulation gives an annulus centered at RA(2000)=78.201 (05h 12m 48s)
  Dec(2000)=+17.575 (+17d 34' 32"), whose radius is 51.547  0.508 deg
(3sigma). The Fermi/GBM ground position (Preece, GCN 8678) is 5 deg away 
from the center line of the annulus. The Konus ecliptic latitude 
response constrains the arrival direction to a band between ecliptic 
latitudes +30 and +53 degrees.

Combining all these data, we have triangulated
this burst to a single error box, whose corners are:
-----------------------------------------------------
     RA(2000), deg              Dec(2000), deg
-----------------------------------------------------
1: 129.016 (08h 36m 04s)   +50.756 (+50d 45' 22")
2: 122.577 (08h 10m 18s)   +58.308 (+58d 18' 28")
3: 121.670 (08h 06m 41s)   +57.174 (+57d 10' 27")
4: 127.051 (08h 28m 12s)   +51.125 (+51d 07' 32")
-----------------------------------------------------

Preliminary analysis of the Konus-Wind data yields
a burst fluence of ~7x10^-5 erg/cm2 (in the 20 keV - 5 MeV range),
and an Epeak of the time-integrated spectrum of ~450 keV.

Detailed spectral parameters will be reported later.

The K-W light curve of this GRB and IPN triangulation map is
available at http://www.ioffe.ru/LEA/GRBs/GRB081215_T67721/


GRB_name: GRB081221A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8703
SUBJECT: Swift/UVOT observations of GRB 081221
DATE:    08/12/22 14:56:47 GMT
FROM:    Paul Kuin at MSSL  <npkuin@googlemail.com>

N. P. M. Kuin (MSSL/UCL) and E. A. Hoversten (PSU) report
on behalf of the Swift UVOT team.

The Swift UltraViolet/Optical Telescope (UVOT) began settled
observations of GRB081221 (Swift BAT trigger number 337889,
Hoversten et al., GCN Circ.  8687), on December 21, 2008, at
16:22:29, 78 seconds after the trigger with a white finding chart.

We do not detect any new source at the enhanced XRT position
reported in GCN Circ. 8690 (Evans et al.).

The observed magnitude upper limits for GRB 081221 are given below
for the first observations and the summed exposures in the UVOT
filters:

Filter Tstart(s) Tstop(s)  Exp(s)  Magnitude

wh       78       228     149.8    >20.84  (3-sigma UL)
v       619       639      19.4    >17.89  (3-sigma UL)
b       545       565      19.4    >18.85  (3-sigma UL)
u       290       540     245.8    >20.15  (3-sigma UL)
uvw1    668       688      19.4    >18.10  (3-sigma UL)
uvm2    644       664      19.5    >17.71  (3-sigma UL)
uvw2    595       615      19.4    >18.08  (3-sigma UL)

wh       78      6086     381.0    >21.41  (3-sigma UL)
v        59     34696    2192.4    >20.74  (3-sigma UL)
b       545     41269    1765.2    >21.55  (3-sigma UL)
u       290     40478    3667.7    >21.69  (3-sigma UL)
uvw1    668     39565    3758.4    >21.57  (3-sigma UL)
uvm2    644     45178    3409.4    >21.55  (3-sigma UL)
uvw2    595     33783    2005.6    >21.35  (3-sigma UL)

The values quoted above are on the UVOT Photometric System
(Poole et al, 2008, MNRAS 383,627). They are not corrected for the
expected galactic reddening of E(B-V) = 0.021 in the direction of
the burst (Schlegel et al. 1998).


GRB_name: GRB081221A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8704
SUBJECT: GRB081221: Fermi GBM observation
DATE:    08/12/22 16:09:29 GMT
FROM:    Colleen A. Wilson at NASA/MSFC/NSSTC  <colleen.wilson@nasa.gov>

Colleen A. Wilson-Hodge (NASA/MSFC) reports on behalf of the Fermi GBM
Team: 

"At 16:21:12.22 UT on 21 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081221 (trigger 251569273 / 081221681),
which was also detected by the SWIFT-BAT and XRT (Hoversten et al. 2008,
GCN 8687).

The on-ground calculated location, using the GBM trigger data, is
RA = 17.2, DEC = -24.8 (J2000 degrees, equivalent to 01 h 09 m, -24 d 50'),
with an uncertainty of less than 1.0 degree (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 78 degrees.

The GBM light curve consists of a weak initial peak and a bright second peak
with a duration (T90) of about 40 s (8-1000 keV). The time-averaged spectrum
from T0+0.003 s to T0+38.401 s is adequately fit by a Band function with
Epeak = 77 +/- 1 keV, alpha = -0.42 +/- 0.03, and beta = -2.91 +/- 0.08.
These spectral parameters are consistent with Konus-Wind observations
(Golenetskii et al. 2008, GCN 8694.)

The event fluence (8-1000 keV) in this time interval is
(3.7 +/- 0.1)E-05 erg/cm^2. The 64-msec peak photon flux measured starting
from T0+19.3923 s in the 8-1000 keV band is 33 +/- 9 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081222A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8705
SUBJECT: GRB 081222: Swift XRT refined analysis
DATE:    08/12/22 16:14:12 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

Dirk Grupe (PSU) reports on behalf of the Swift-XRT team:


The XRT began observing the field of GRB 081222 (trigger=337914; Grupe et al.,
GCN Circ 8691) on 2008-December-22 at 04:54:51.7 UT, 51.8 seconds after
the BAT trigger.


The 0.3-10 keV X-ray light curve of the first five orbits
displays a smooth light curve that can be fitted with an initial decay slope
alpha1 = 0.90+/-0.02 with a break at 1420+/-100s followed by a steeper decay
slope alpha2=1.20+/-0.02.

The spectrum of the Windowed Timing data of the first orbit
can be well fitted by an absorbed single
power law model with a photon
index Gamma = 2.01 +/- 0.20 and a column density
NH=(4.61+/-0.80)e20 which is in excess of the Galactic column density in the
direction of the burst of NH-gal=2.24e20 (Kalberla et al. 2005).
The photon counting mode data of the first five orbits are consistent 
with this
result.


If the underlying power law decay of 1.2
continues as is, we predict an XRT count rate
of 0.030 counts/s at T+24 hours or 1e-12 ergs/s/cm2 and at T+48 hours 0.015
counts/s or 5e-13 ergs/s/cm2.

This circular is an official product of the Swift-XRT team.

[GCN OPS NOTE(23dec08):  Per author's request, the "081221" in the first line
was changed to "081222".]


GRB_name: GRB081215A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8706
SUBJECT: Konus-Wind observation of very bright GRB 081215A
DATE:    08/12/22 16:19:07 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The very bright GRB 081215A (Fermi/GBM trigger 251059717 / 081215784: 
Preece, GCN 8678, 8679) localized by IPN (Golenetskii et al., GCN 8702) 
triggered Konus-Wind at T0=67721.281 s UT (18:48:41.281).

As observed by Konus-Wind the burst
had a fluence of (7.99 +/- 0.68)x10^-5 erg/cm2,
and a 16-ms peak flux measured from T0+0.448 s
of (1.24 +/- 0.17)x10^-4 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+12.544 s) is well be fitted (in the 20 keV - 5 MeV
range) by GRB (Band) model for which:
the low-energy photon index is alpha = -0.870(-0.064, +0.070),
the high energy photon index beta = -2.20(-0.19, +0.13),
the peak energy Ep = 447(-52, +60) keV (chi2 = 72.2/76 dof).
The spectrum of the most intense peak
(from T0+0.256 s to T0+0.512 s) is well fitted (in the 20 keV-10 MeV
range) by GRB (Band) model for which:
the low-energy photon index is alpha = -0.49(-0.10, +0.12),
the high energy photon index beta = -2.38(-0.37, +0.23),
the peak energy Ep = 1001(-174, +193) keV (chi2 = 57.5/58 dof).
In this spectrum a statistically significant emission is clearly seen up 
to 10 MeV.

All the quoted errors are at the 90% confidence level.

[GCN OPS NOTE(23dec08): Per author's request, "2.38(-0.37, +0.23)"
was changed to "-2.38(-0.37, +0.23)".]


GRB_name: GRB081222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8707
SUBJECT: GRB081222 optical limit by "Pi of the Sky"
DATE:    08/12/22 16:23:11 GMT
FROM:    Marcin Sokolowski at Soltan Inst. Nuc Studies,Warsaw  <msok@fuw.edu.pl>

M.Cwiok, W.Dominik, G.Kasprowicz, A.Majcher, A.Majczyna,
K.Malek, L.Mankiewicz, K.Nawrocki, L.W.Piotrowski,
D.Rybka, M.Sokolowski, J.Uzycki, G.Wrochna, M.Zaremba, A.F.Zarnecki
on behalf of "Pi of the Sky" collaboration http://grb.fuw.edu.pl

During the night 20081222 the "Pi of the Sky" apparatus observed the
position of GRB081222 in the sky scan mode.
Three 10s images of this field have been taken at 02:10:44 - 02:11:21
( 2 hours 43 min 16 sec before the GRB).
No new object is seen within the error box and the limit is 12.5 
magnitudo.

After receiving the trigger from Swift, the field was observed 63s after
the GRB. No new object has been found within the Swift-BAT error box.
The limiting magnitude (unfiltered) on single 10s exposures is:

         04:55:03 - 04:55:13 - 12.0 mag
         04:55:16 - 04:55:26 - 12.0 mag
         04:55:28 - 04:55:38 - 12.0 mag

The field was observed until 06:00:17, no new object brighter then 12.0mag
was observed. The limit on 20 coadded images is 12.5 mag.


GRB_name: GRB081221A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8708
SUBJECT: GRB 081221, Swift-BAT refined analysis
DATE:    08/12/22 19:27:08 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc@milkyway.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
E. A. Hoversten (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. M. Palmer (LANL), A. M. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+873 sec from the recent telemetry 
downlink,
we report further analysis of BAT GRB 081221 (trigger #337889)
(Hoversten, et al., GCN Circ.  8687).  The BAT ground-calculated 
position is
RA, Dec = 15.801, -24.542 deg which is
  RA(J2000)  =  01h 03m 12.2s
  Dec(J2000) = -24d 32' 32.8"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 61%.

The mask-weighted light curve shows two main overlapping peaks, the smaller
from about T+0 to T+12 sec and the larger from about T+12 to T+40 sec, with
multiple subsidiary peaks and an extended tail visible to about T+150 sec.
T90 (15-350 keV) is 34 +- 1 sec (estimated error including systematics).

The time-averaged spectrum from T-0.3 to T+112.6 sec is best fit by a power
law with an exponential cutoff.  This fit gives a photon index 1.21 +- 
0.13,
and Epeak of 69.9 +- 3.9 keV (chi squared 37.73 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 1.81 +- 0.03 x 10-05 
erg/cm2
and the 1-sec peak flux measured from T+21.42 sec in the 15-150 keV band is
18.2 +- 0.5 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.86 (chi squared 119.90 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/337889/BA/


GRB_name: GRB081222A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8709
SUBJECT: GRB 081222, Swift-BAT refined analysis
DATE:    08/12/22 19:28:59 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc@milkyway.gsfc.nasa.gov>

E. E. Fenimore (LANL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), D. Grupe (PSU), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-119 to T+183 sec from the recent telemetry 
downlink,
we report further analysis of BAT GRB 081222 (trigger #337914)
(Grupe, et al., GCN Circ. 8691).  The BAT ground-calculated position is
RA, Dec = 22.748, -34.095 deg which is
  RA(J2000)  =  01h 30m 59.5s
  Dec(J2000) = -34d 05' 41.4"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The burst was in the fully-coded field of view.

The mask-weighted light curve shows a main peak with several subpeaks
from about T+0 to T+20 sec and an exponential tail visible to about
T+70 sec.  T90 (15-350 keV) is 24 +- 3 sec (estimated error including
systematics).

The time-averaged spectrum from T-0.6 to T+38.0 sec is best fit by a 
power law
with an exponential cutoff.  This fit gives a photon index 1.08 +- 0.15,
and Epeak of 131 +- 31 keV (chi squared 45.61 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 4.8 +- 0.1 x 10^-06 
erg/cm2
and the 1-sec peak flux measured from T+3.45 sec in the 15-150 keV band is
7.7 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.48 +- 0.03 (chi squared 68.25 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/337914/BA/


GRB_name: GRB081204C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8710
SUBJECT: GRB 081204C: Fermi GBM detection
DATE:    08/12/22 22:37:27 GMT
FROM:    Valerie Connaughton at MSFC  <valerie@nasa.gov>

Valerie Connaughton (UAH)
reports on behalf of the Fermi GBM Team:

"At 00:05:24.24 UT on 04 December 2008, the Fermi Gamma-Ray Burst
Monitor triggered and located GRB 081204C
(trigger 250041925 / 081204004).

The on-ground calculated location, using the GBM trigger
data, is RA = 61.9, DEC = -61.5 (J2000 degrees,
equivalent to 04h 08m, -61d 30'), with an uncertainty
of 4.0 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 56 degrees.


The GBM light curve consists of a single weak pulse
with a duration (T90) of about 4.7 s (8-1000 keV).
The time-averaged spectrum from T0-0.8 s to T0+2.3 s is
adequately fit by a Power Law of index around -1.4.
Although the Band function is preferred statistically,
the burst is too weak to constrain its parameters.

The event fluence (8 -- 1000 keV) in this time interval
using a simple power-law fit is (1.48 +/- 0.3)E-06 erg/cm^2.
The 1-sec peak photon flux measured starting from T0 s
in the 8 - 1000 keV band is 7.2 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8711
SUBJECT: GRB 081221: Probable host galaxy in Keck imaging
DATE:    08/12/23 11:23:47 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom (UC Berkeley), J. Kalirai (STSCI), R. 
Strickler, E. Ramirez-Ruiz (UCSC), and A. A. Miller (UCB) report:

We began a series of deep optical imaging exposures on the field of GRB 
081221 (Hoversten et al., GCN 8687) using the Keck I telescope (+LRIS) 
starting at 2008-12-23 at 5:06 UT.  We acquired 10x330s in g-band and 
10x300s in I-band (simultaneously using the 560 dichroic).

A extended source coincident with the Gemini (Tanvir et al., GCN 8698) 
and Swift XRT (GCN 8690) afterglow positions is clearly detected in our 
g-band stack, which we tentatively identify as the host galaxy.  The 
magnitude within a 1.0" aperture of this object is approximately B~25.4 
(calibrated relative to the USNO star at RA=15.797098, dec=-24.412259, 
B2=19.59).  It is only marginally detected in the I-band imaging, with 
an estimated magnitude of I~24.5, though photometry in this band is 
complicated by blending with a nearby object.

The detection of a host galaxy would be consistent with a low-redshift 
origin (GCN 8698).  Within the significant uncertainties of the 
photometric calibration the color of the galaxy appears typical of 
normal GRB hosts.  Further analysis is planned.

An image of the field is posted to:
http://lyra.berkeley.edu/~dperley/081221/081221hostkeck.png


GRB_name: GRB081222A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8712
SUBJECT: GRB081222: Swift/UVOT further observations
DATE:    08/12/23 12:15:56 GMT
FROM:    Alice Breeveld at MSSL-UCL  <aab@mssl.ucl.ac.uk>

Alice Breeveld (MSSL), Wayne Landsman (GSFC), Paul Kuin (MSSL) and  
Dirk Grupe (PSU) report on behalf of the Swift/UVOT team:

Further analysis of Swift/UVOT data of GRB081222 (Grupe et al., GCN  
Circ. 8691), shows that the burst was detected in the v and b filters  
in addition to the white and u filters described in the initial  
circular (Breeveld et al., GCN Circ. 8696). The source is not detected  
in any of the UV filters, in single or co-added exposures. The initial  
magnitudes and upper limits are given in the table below:

Filter    Tstart(s) Tstop(s)     Exp(s)   Magnitude
white   60            210           147        14.84+/-0.02
white   873          1023         147       17.36+/-0.03
v           602          622           20          16.20+/-0.02
b           528          548           20          16.86+/-0.02
u           272           522           246       16.32+/-0.03
uvw1    652          1815         142        >20.9  (3-sigma UL)
uvm2    627          1790         127        >21.0  (3-sigma UL)
uvw2    577          1914         124        >21.1  (3-sigma UL)

A 49s UV grism spectrum was obtained beginning 216s after the  
trigger.  The very low S/N quicklook spectrum shows a continuum of  
about 3e-15 erg/s/cm2/A longward of ~3400 A.  No flux is detected  
shortward of 3400 A, even though the grism sensitivity increases  
toward shorter wavelengths.  If this is the wavelength of the Lyman  
edge, then the redshift of GRB081222 is ~2.7.  The detection of  
GRB081222 in the u filter and the non-detection in UVW1 filter are  
consistent with this redshift.

The values quoted above are in the UVOT photometric system (Poole et  
al. 2008, MNRAS, 383, 627) and are not corrected for the expected  
Galactic extinction corresponding to a reddening of E(B-V)=0.021 mag  
in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB081222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8713
SUBJECT: GRB 081222: Gemini-South absorption redshift
DATE:    08/12/23 14:58:35 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara, D. B. Fox (Penn State), S. B. Cenko  (Berkeley) and E. Berger
(Harvard) report on behalf of a larger collaboration:

Starting at 01:02 UT on 2008 December 23  we observed the optical
counterpart of GRB 081222 (Grupe et al., GCN 8691, Covino  et al.,
GCN 8692 and Updike et al. 8693) using Gemini-South with the GMOS-South
spectrograph (R~1600).
We acquired 2x900s spectra covering the wavelength range 4000A-8000A.

We detect a damped Lyman-alpha system (DLA) at redshift z=2.77.

We also detect several metal absorption features which we interpret as
SiIV(1393,1402), SiII1526 and 1260, SiII*1264, CII1334, CII*1335,
CIV(1548,1550), FeII1608 and NiII(1454) at the same redshift.

In combination with the strong metal absorption features, the detection of
a DLA at z = 2.77 confirms that this is the redshift of GRB 081222 and its
host galaxy.

We thank the Gemini staff, in particular Henry Lee, for conducting
these observations.


GRB_name: GRB081222A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8715
SUBJECT: GRB 081222: Fermi GBM observation
DATE:    08/12/23 16:28:19 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E.Bissaldi (MPE) and S. McBreen (UCD/MPE)
report on behalf of the Fermi GBM Team: 


"At 04:54:00.25 UT on 22 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081222 (trigger 251614441 / 081222204),
which was also detected by the Swift-BAT (Grupe et al., GCN Circular 8691
and Fenimore et al., GCN Circular 8709).
 
The angle from the Fermi LAT boresight is 50 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of a main pulse with a
duration (T90) of about 30 s (8-1000 keV) and T50
of about 10 s (8-1000 keV). 

The time-averaged spectrum from T0 to T0+11.52 s is 
best fit by a Band function with Epeak = 134 +/- 9,
alpha = -0.55 +/- 0.07 and beta  = -2.10 +/- 0.06.

The event fluence (8-1000 keV) in this time interval is 
(1.35 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux 
measured starting from T0+3.3 s in the 8-1000 keV band
is 14.8 +/- 1.4 ph/s/cm^2.


The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog." 


GRB_name: GRB081222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8716
SUBJECT: VLA radio upper limit on GRB 081222
DATE:    08/12/23 16:34:08 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on
behalf of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward
optically bright GRB 081222 (GCN 8691) at a frequency of 8.46 GHz
on 2008 Dec 23.17 UT. The GRB radio afterglow is undetected and
the peak radio flux at the REM optical afterglow position (GCN 8692)
is 54  53 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB081222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8717
SUBJECT: GRB 081222:Optical afterglow observation
DATE:    08/12/23 18:13:10 GMT
FROM:    Rupak Roy at ARIES  <roy@aries.ernet.in>

Rupak Roy, Brajesh Kumar, S. B. Pandey
and Brijesh Kumar (ARIES, NainiTal, India, on behalf of larger
Indian GRB collaboration) 


GRB 081222, localized by Swift (Grupe
et al. GCN 8691), was observed with 1.04m telescope at NainiTal
starting ~ 9 hours after the burst in R_c  and I_c
filters.
Photometry of the co-added R_c frames (300 sec x 6)
did not detect the optical afterglow candidate (Covino et al. GCN
8692) down to a limiting magnitude of ~ 21 mag in comparison to
nearby USNO stars.
This message may be cited.


GRB_name: GRB081222A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8718
SUBJECT: GRB 081222: Gemini-N confirmation of redshift z=2.77
DATE:    08/12/23 20:14:39 GMT
FROM:    John Graham at STScI  <graham@stsci.edu>

J. F. Graham (STScI/JHU), N. R. Tanvir (U. Leicester), A. S. Fruchter 
(STScI), K. Wiersema (U. Leicester), A. J. Levan (U. Warwick) report on 
behalf of a larger collaboration:

We observed the afterglow of GRB 081222 with Gemini-North/GMOS Nod & 
Shuffle spectroscopy beginning 22 Dec 2008 06:38 UT, approximately 105 
minutes post-burst. From absorption lines of SiII, CIV, and FeII, we 
confirm the redshift reported in GCN 8713 (Cucchiara et al.) of z=2.77. 
We also find tentative evidence for a lower redshift system at z=2.74.

We thank the Gemini staff, in particular Ricardo Schiavon, for 
conducting these observations.


GRB_name: GRB081221A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8719
SUBJECT: GRB 081221: GROND observations
DATE:    08/12/23 20:22:43 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 081221: GROND observations 

P. Afonso, T. Kruehler, J. Greiner, C. Clemens (all MPE Garching) and A.
Updike (Clemson University) report on behalf of the GROND team: 

GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m ESO/MPI
telescope at La Silla Observatory (Chile) imaged the field of GRB 081221
(Swift trigger 337889, Hoversten et al., GCN #8687) on two epochs
simultaneously in g'r'i'z'JHK. This burst was also detected by Konus-Wind
(Golenetskii et al. GCN #8694) and the Fermi GBM (Wilson-Hodge, GCN
#8704). 

The first epoch started on 2008-12-22 at 01:33:08 UT roughly 9 hours after
the trigger and consisted of 16 images of 375s exposure in g'r'i'z' and
480 images of 10s exposure in JHK. An equal amount of images were obtained
during the second epoch in the following night from 01:19:56 UT on, 33
hours after the burst. 

Inside the refined XRT error circle (Stroh & Hoversten, GCN #8701) we
detect in both epochs the object reported by Tanvir et al.(GCN #8698) and
Perley et al. (GCN #8711) in g'r'i', but not in z'JHK. 

No variability between the two epochs is evident, and no other source is
detected inside the XRT error circle. 

Preliminary VEGA magnitudes from the second epoch calibrated against
USNO-B field stars and upper limits are as follows: 

g' = 25.2 +/- 0.3
r' = 24.7 +/- 0.2
i' = 24.4 +/- 0.4
z' > 24.0
J > 21.0
H > 19.8
K > 19.0 

Given the large errors due to image statistics, photometric calibration
and complicated photometry as pointed out by Perley et al. (GCN #8711),
these values are consistent with what is reported in GCNs #8698 and #8711. 

 


GRB_name: GRB081223A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8720
SUBJECT: GRB 081223: Fermi GBM detection
DATE:    08/12/24 12:33:20 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

Elisabetta Bissaldi (MPE)
reports on behalf of the Fermi GBM Team: 


"At 10:03:57.15 UT on 23 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081223 (trigger 251719438 / 081223419).
The on-ground calculated location, using the GBM trigger
data, is RA = 116.7, Dec = 33.5 (J2000 degrees,
equivalent to 07h 47m, 33d 30'), with an uncertainty
of 6.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 28 degrees.

This short burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of a single spike
with a duration (T90) of about 890 ms (8-1000 keV).
The time-averaged spectrum from T0-0.078 s to T0+0.434 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.63 +/- 0.10 and
the cutoff energy, parameterized as Epeak, is 280 +/- 30 keV
(chi squared 334 for 318 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(1.20 +/- 0.10)E-06 erg/cm^2. The 64-ms peak photon flux
measured starting from T0+0.114 s in the 
8-1000 keV band is 22 +/- 3 ph/s/cm^2.


The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081222A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8721
SUBJECT: Konus-Wind observation of GRB 081222
DATE:    08/12/24 14:14:00 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The long GRB 081222 (Swift-BAT trigger #337914: Grupe et al., GCN 8691; 
Fenimore et al., GCN 8709) triggered Konus-Wind at T0=17642.534 s UT 
(04:54:02.534).

The burst light curve shows a single pulse with a duration of ~12 s.
There is a hint of the weak tail detected by the Swift-BAT (Fenimore et 
al., GCN 8709) in the K-W G1 band (~20-80 keV).

As observed by Konus-Wind the burst
had a fluence of 1.32(-0.40, +0.48)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+4.688 s
of 2.22(-0.73, +0.87)x10^-6 erg/cm2/s
(both in the 20 keV - 1 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+16.640 s) can be fitted (in the 20 keV - 1 MeV
range) by GRB (Band) model for which:
the low-energy photon index is alpha = -0.67(-0.33, +0.39),
the high energy photon index beta = -2.35(-1.25, +0.30),
the peak energy Ep = 165(-29, +47) keV (chi2 = 63.0/51 dof).

All the quoted errors are at the 90% confidence level.

Assuming z = 2.77 (Cucchiara et al., GCN 8713; Graham et al., GCN 8718) 
and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, 
Omega_\Lambda = 0.73, the isotropic energy release E_iso ~2.4x10^53 erg, 
the peak luminosity (L_iso)_max ~ 1.5x10^53 erg/s, and Ep_rest ~600 keV.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB081222_T17642/


GRB_name: GRB080810A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8722
SUBJECT: GRB 080810: optical observations
DATE:    08/12/24 14:21:54 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (SAI MSU), I. Korobtsev (ISTP),  A. Pozanenko (IKI), E. Klunko 
(ISTP), N. Bochkarev (SAI MSU), E. Karitskaja (Institute of Astronomy),  on 
behalf of larger  GRB follow up collaboration  report:

We observed the afterglow of GRB 080810 (Page et al. GCN 8080) with 1.5  m 
telescope of Sayan observatory (Mondy) under good weather  conditions. 
Series of R and B images were obtained between Aug. 10 (UT) 
16:50:03 -18:17:06.  While we clearly detect afterglow in single R images, 
the afterglow is not detected in a combined image obtained in B. A 
photometry of the combined images is based on several SDSS nearby stars:

  T0+         Filter  Exp.    mag.           Upper_Limit seeing
 mid., days                                 (3 sigma)

  0.1599      B      14x60    n/d            19.26      ~2.7"
  0.1786      R      30x60   17.98 +/- 0.13  20.85      ~2.2"
  0.2026      R      30x60   18.10 +/- 0.17  21.14      ~2.0"

The photometry in R-band is an agreement with power law decay index of 
light curve (alpha = 1.12) between 400 s and 1 day after the burst  reported 
by Thoene et al (GCN 8106). 


GRB_name: GRB081224A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8723
SUBJECT: GRB 081224: Fermi GBM Detection & LAT Localization
DATE:    08/12/25 00:43:55 GMT
FROM:    Valerie Connaughton at MSFC  <valerie@nasa.gov>

Colleen Wilson-Hodge (MSFC) and Valerie Connaughton (UAH) on behalf
of the Fermi-GBM team,
Francesco Longo (INFN Trieste) and Nicola Omodei (INFN Pisa) on behalf
of the Fermi LAT team.

"On 21:17:55.41 UT of Dec 24 2008 GBM detected a bright GRB.
Preliminary analysis of the real-time Fermi GBM  data from Trigger number
251846276/ GRB 081224887 / GRB 081224
shows that this is a FRED (Fast Rise Exponential Decay) lasting
approximately 50 seconds with a peak of FWHM 15 sec long.    It is
located to a position of RA=206.2, Dec= 73.3  with statistical
uncertainty 1 deg (and an estimated systematic uncertainty of 2-3 deg)
which places it at 16 deg to the LAT boresight.

The Large Area Telescope (LAT) also provided a tentative onboard
localization:
RA=213.367, DEC=74.233 (J2000)
corresponding to:
RA: +14h 13m 28s  (J2000),
DEC: +74d 13' 60" (J2000)
with on board estimated error of 36 arcmin (statistical only).
The current estimated onboard systematic error is 1 deg.

The estimated LAT position is  2.2 deg from the ground GBM location
and may be  considered more reliable. 
Accurate LAT localization and spectral analysis will
await the downlink of both LAT and GBM data which could take several
hours.

We further report that the Fermi Observatory executed a maneuver
following  this trigger and will track the burst location for the next
5 hours, subject  to Earth-angle constraints.

We encourage follow up observations.
The Fermi LAT point of contact for this burst is Francesco Longo
(francesco.longo@ts.infn.it).
The Fermi GBM point of contact is Valerie Connaughton
(valerie@nasa.gov)

The Fermi LAT is a pair conversion telescope designed to cover the
energy band from 20 MeV to greater than 300 GeV. It is the product of an
international collaboration between NASA and DOE in the U.S. and many
scientific institutions across France, Italy, Japan and Sweden.
This message can be cited."


GRB_name: GRB081222A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8724
SUBJECT: GRB 081222: MITSuME optical observation
DATE:    08/12/25 01:51:58 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida@oao.nao.ac.jp>

D. Kuroda, M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama,
H. Toda (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf
of the MITSuME collaboration:

We observed the field of GRB 081222 (Grupe et al. GCN 8691) with
the optical three color (g', Rc and Ic) imager attached to the
MITSuME 50cm telescope of Okayama Astrophysical Observatory on
Dec.22 2008 UT. We detected a fading point source at the position
of the X-ray - optical afterglow candidate (Covino et al. GCN 8692;
Updike et al. GCN8693; Grupe GCN 8705) in Rc band. Photometric
results are listed below. We used GSC2.3 catalog for flux
calibration.

# Mid-MJD      Mid-UT   EXP-T    g'       Rc          Ic
-------------------------------------------------------------
54822.401100  09:37:36  540.0  >18.3  18.0+/-0.3  >17.8
54822.438455  10:31:23 2940.0  >19.2  18.9+/-0.3  >18.2
54822.469650  11:16:18 4500.0  >19.2  19.3+/-0.4  18.6+/-0.3
-------------------------------------------------------------


GRB_name: GRB081224A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8725
SUBJECT: GRB 081224: Swift-XRT observation
DATE:    08/12/25 10:17:22 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT 
team:

Swift performed a Target of Opportunity follow-up observation of the Fermi 
GBM and LAT burst GRB 081224 (Wilson-Hodge et al., GCN Circ. 8723), 
starting 18 ks after the trigger. 

There is a faint X-ray source (~6.7x10^-3 count s^-1) within the XRT field 
of view, detected in the 3.6 ks of data collected so far. Using 1193 s of 
XRT Photon Counting mode data and 1 UVOT image, we find an astrometrically 
corrected X-ray position (using the XRT-UVOT alignment and matching UVOT 
field sources to the USNO-B1 catalogue): RA, Dec = 213.1494, 74.1999, 
which is equivalent to:

RA (J2000):   14 12 35.85
Dec (J2000): +74 11 59.5

with an uncertainty of 3.4 arcsec (radius, 90% confidence).

However, we note that the uncertainty on the LAT position (36 arcmin) is 
larger than the XRT field of view, so Swift has not observed the complete 
error circle. We also cannot say whether the XRT source is fading at this 
time.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB081224A
Detection_method: retraction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8726
SUBJECT: GRB081224: LAT retraction
DATE:    08/12/25 14:50:33 GMT
FROM:    Julie McEnery at UMBC/GSFC  <mcenery@milkyway.gsfc.nasa.gov>

Julie McEnery (NASA/GSFC) reports on behalf of the LAT collaboration

On-ground analysis of GRB 081224 did not confirm the tentative LAT 
on-board detection reported in GCN 8723. The apparent onboard excess was 
likely a statistical fluctuation.


GRB_name: GRB081211B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8727
SUBJECT: GRB 081211B: optical observations
DATE:    08/12/25 18:09:36 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy), Ju. 
Babina  (CrAO), A. Pozanenko (IKI) on behalf of larger GRB follow up 
collaboration report:

We observed  the field of GRB 081211B (Copete et al., GCN 8661)   with 
Zeiss-600 telescope of Mt. Terskol observatory on Dec.13 in R-band. In the 
XRT error box (Page et al., GCN 8666) we do not detect any optical source. A 
photometry of the combined image is following:

Mid time (UT)      Exposure   R_mag (3 sigma)
                   s

08-12-13 02:10:40  85x60      >21.1 


GRB_name: GRB080810A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8728
SUBJECT: GRB 080810: optical observations
DATE:    08/12/25 18:17:47 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (SAI MSU), R. Karimov (MAO),  A. Pozanenko (IKI), M. Ibrahimov 
(MAO)  on behalf of larger GRB follow up collaboration  report:

We observed the afterglow of GRB 080810 (Page et al. GCN 8080) with  AZT-22 
(1.5 m) telescope of Maidanak observatory (MAO) in  R band  on Aug. 12 (UT) 
(20:18:17 -  21:07:58) and Aug. 14 (20:26:35  - 21:33:00).   A photometry of 
combined images is based on several SDSS DR6 field stars:

T0+         Filter  Exp.  mag.           UL
mid., days                               (3 sigma)


2.315      R      2700    21.36 +/-0.09  23.10
4.326      R      3600    n/d            22.30

The photometry in R-band is an agreement with power law decay index  (alpha 
= 1.8)  reported by Thoene et al (GCN 8106) for this phase of  the light 
curve. 


GRB_name: GRB081226A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8729
SUBJECT: GRB 081226: Swift detection of a possible short-hard burst
DATE:    08/12/26 01:21:22 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

O. Godet (U Leicester), W. H. Baumgartner (GSFC/UMBC),
D. N. Burrows (PSU), E. A. Hoversten (PSU), J. A. Kennea (PSU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 01:03:37 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 081226 (trigger=338177).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 120.527, -69.006 which is 
   RA(J2000) = 08h 02m 06s
   Dec(J2000) = -69d 00' 20"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a short hard burst
structure with a duration of about 0.5 sec.  The peak count rate
was ~4000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 01:05:11.9 UT, 94.6 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 120.50054, -69.02994 which is
equivalent to:
   RA(J2000)  = 08h 02m 0.13s
   Dec(J2000) = -69d 01' 47.8"
with an uncertainty of 4.5 arcseconds (radius, 90% containment). This
location is 92 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.19e+21 cm^-2 (Kalberla et al. 2005). 

The UVOT data has not yet been received so it is not possible to
comment on the UV/optical nature of the burst at this time.  There is
a 7th magnitude source nearby which will complicate UVOT observations. 

Burst Advocate for this burst is O. Godet (og19 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB081226A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8730
SUBJECT: GRB 081226: ROTSE-III Optical Limits 
DATE:    08/12/26 01:32:34 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

B. E. Schaefer (Louisiana State), E.S. Rykoff (UCSB), F. Yuan (U Mich), 
report on behalf of the ROTSE collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,
responded to GRB 081226 (Swift trigger 338177; Godet, GCN 8729), producing
images beginning 8.8 s after the GCN notice time. An automated response
took the first image at 01:04:02.8 UT, 25.4 s after the burst, under
excellent conditions. We took 10 5-sec, 20 20-sec exposures.  These
unfiltered images are calibrated relative to USNO A2.0 (R). Imaging is on
going.

Comparison to the DSS (second epoch) reveals no new sources within the 
3-sigma Swift/BAT error circle or the XRT error circle, for both single 
images and coadding into sets of 10; the field is not crowded. Individual 
images have limiting magnitudes ranging from 16.8-17.4; we set the 
following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
01:04:02.8   01:04:07.8         5     17.0           25.4       N
01:04:02.9   01:05:19.0        76     17.8           25.5       Y


GRB_name: GRB081226A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8731
SUBJECT: GRB 081226: GROND afterglow candidate
DATE:    08/12/26 03:08:29 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 081226: GROND afterglow candidate 


P. Afonso, T. Kruehler (both MPE Garching), S. Klose (TLS Tautenburg), and 
J. Greiner (MPE Garching) report on behalf of the GROND team: 

GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m ESO/MPI 
telescope at La Silla Observatory (Chile),started observations of the field 
of GRB 081226 (Godet et al. 2008, GCN #8729) in g'r'i'z'JHK at 01:14 UTC, 11 
min after the burst. We detect a faint optical source in the XRT error 
circle (Godet et al. 2008, GCN #8729) at: 

RA(J2000): 08:01:59.92
DEC(J2000): -69:01:47.4 

with uncertainties of 0.5". 

At a midtime of 01:57 UTC, we measure a rough preliminary r' band magnitude 
of 24.3 calibrated with the GROND zeropoint. 

No statement about variability can be made at this point. Observations are 
ongoing. 


GRB_name: GRB081226A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8732
SUBJECT: GRB 081226:  Gemini-South imaging
DATE:    08/12/26 03:26:41 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard), A. Cucchiara, and D. B. Fox (Penn State) report:

"We imaged the error circle of GRB 081226 (GCN 8729) with GMOS on the
Gemini-S telescope starting on 2008 Dec 26.04 UT.  In a single 300 sec
r-band image we detect the object located by GROND within the XRT
error circle (GCN 8731).  In addition, we find a second, fainter source
within the error circle at (J2000):
 RA = 08:02:00.44
 DEC = -69:01:48.9
with an uncertainty of about 0.5" in each coordinate.  Additional
observations are on-going to determine if either of these two sources is
fading."


GRB_name: GRB081226A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8733
SUBJECT: GRB 081226:  Gemini-South spectrum of possible afterglow
DATE:    08/12/26 04:51:20 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard), A. Cucchiara, and D. B. Fox (Penn State) report:

"We obtained spectroscopic observations of the possible afterglow of GRB
081226 (GCNs 8731, 8732) with GMOS on the Gemini-South telescope using the
R400 grating with a central wavelength of 6000A for a total of 2400 sec.
We detect smooth continuum emission but no obvious absorption or emission
features in the wavelength range 4000-8000A.  Further analysis is
on-going."


GRB_name: GRB081226B
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8734
SUBJECT: GRB 081226B: a short-hard GRB detected by INTEGRAL
DATE:    08/12/26 14:24:19 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

S.Mereghetti, A.Paizis (IASF-Milano), D.Gotz (CEA-Saclay), M.Turler,
V.Beckmann, M. Beck (ISDC, Versoix), and J. Borkowski (CAMK, Torun) on
behalf of the IBAS Localization Team report:

A short hard GRB consisting of a single peak with duration of  about 0.7 s 
has been detected by IBAS in IBIS/ISGRI data at 12:13:11 UT on December 26th. 

The refined coordinates (J2000)  are:

RA = 25.495 [degrees]
DEC= -47.439 [degrees]

with an uncertainty of 2.5 arcmin (90% c.l.).

A preliminary analysis gives a peak flux in the 20-200 keV range of  
about 3 ph/cmq/s (0.2 s integration time) and a fluence over the same energy
range of about 10e-7 erg/cmq.

A plot of the light curve will be posted at

http://ibas.iasf-milano.inaf.it/IBAS_Results.html

This message can be cited.


GRB_name: GRB081226A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8735
SUBJECT: GRB 081226A: Swift-BAT refined analysis
DATE:    08/12/26 16:12:39 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
O. Godet (U Leicester) C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 081226A (trigger #338177)
(Godet, et al., GCN Circ. 8729).  The BAT ground-calculated position is
RA, Dec = 120.478, -69.014 deg, which is 
   RA(J2000)  =  08h 01m 54.6s 
   Dec(J2000) = -69d 00' 48.6" 
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 32%.
 
The mask-weighted light curve shows a single spike starting at T+0.0 and
ending at T+0.4 sec.  T90 (15-350 keV) is 0.4 +- 0.1 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-0.1 to T+0.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.36 +- 0.29.  The fluence in the 15-150 keV band is 9.9 +- 1.8 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T-0.30 sec in the 15-150 keV band
is 2.4 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/338177/BA/


GRB_name: GRB081226A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8736
SUBJECT: GRB 081226:  Second epoch of Gemini-South imaging
DATE:    08/12/26 16:27:15 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger, A. M. Soderberg (Harvard), A. Cucchiara, and D. B. Fox (Penn
State) report:

"We re-observed the error circle of GRB 081226 (GCN 8729) with GMOS on the
Gemini-South telescope on 2008 Dec 26.349 UT (7.31 hours post burst).  A
comparison to our first epoch of imaging, taken on 2008 Dec 26.112 UT
(1.62 hours post burst; GCN 8732), reveals that neither of the two objects
within the XRT error circle (GCN 8732) have varied in brightness.  This
is confirmed using digital image subtraction with the ISIS package."


GRB_name: GRB081226A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8737
SUBJECT: GRB 081226A: Swift UVOT Upper Limits
DATE:    08/12/26 18:03:45 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) and O. Godet (U Leicester) report on behalf of
the Swift UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 08226A 156s after the BAT trigger (Godet et al., GCN 8729).
We do not detect any source at the Swift XRT position.  The white
filter observation was skipped due to a 7th magnitude star in the field.
The UVOT upper limits are around 20th magnitude so the non-detections do
not conflict with the possible optical afterglow detections in GCN
8731 and GCN 8732 at 24th magnitude.  UVOT magnitude 3-sigma upper
limits are reported in the following table:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
v          461      2276     233         > 19.24
b          410      2226     228         > 20.13
u          155      2051     833         > 20.87
uvw1       510      2176     213         > 19.71
uvm2       486      2151     213         > 19.51
uvw2       436      2252     233         > 19.83

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.16 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).


GRB_name: GRB081226A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8738
SUBJECT: GRB 081226: Swift-XRT refined analysis
DATE:    08/12/26 22:40:57 GMT
FROM:    Olivier Godet at U.of Leicester  <og19@star.le.ac.uk>

O. Godet (U Leicester) on behalf the Swift-XRT team:
 
The Swift-XRT started observing the field of GRB 081226 (trigger number
338177, Godet et al., GCN Circ. 8729) at 2008-12-26 01:05:11.9 UT, 94.5
seconds after the trigger. Using 11.6 ks of photon counting (PC) mode data,
the best XRT position is located at RA, Dec 120.50152, -69.02924 which is
equivalent to:
RA(J2000) = 08h 02m 00.36s
Dec(J2000) = -46d 01' 45.2"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 2.8 arcseconds from the XRT position given in Godet et al. (GCN
Circ. 8729). It is also consistent with the position of the possible 
optical counterpart reported by Afonso et al. (GCN Circ. 8731).
 
The X-ray light curve presently spans 11.6 ks of PC mode data from T+109 s 
to T+42 ks. Due to poor statistics, it is difficult to properly model the
light-curve, which shows a decay (with a slope around 1.8) possibly followed 
by a flattening at later time.
 
The PC X-ray spectrum from the same interval can be well fit by an absorbed
power-law with a photon index of 2.60 +1.61/-0.98 and a column density of 
(6.4 +8.8/-4.6) x 10^21 cm^-2 (the Galactic value is 1.19 x 10^21 cm^-2 in 
the direction of the burst - Kalberla et al. 2005).  The observed 0.4-10.0 
keV flux is (1.8 +0.8/-1.3) x 10^-13 erg cm^-2 s^-1 which corresponds to 
an unabsorbed flux of (4.7 +1.4/-2.5) x 10^-13 erg cm^-2 s^-1.
 
No more Swift observations are planned for this burst.
 
This is an official product of the Swift-XRT team.
 


GRB_name: GRB081224A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8739
SUBJECT: GRB 081224: Suzaku WAM observation of the prompt emission
DATE:    08/12/27 03:55:50 GMT
FROM:    Hidenori Hayasi at Miyazaki U  <hayasi@astro.miyazaki-u.ac.jp>

H. Hayashi E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, 
N. Ohmori, K. Kono (Univ. of Miyazaki)
A. Endo, M. Tashiro, Y. Terada, Y. Urata, K. Onda,
N. Kodaka, K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.),
T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), S. Sugita,
K. Yamaoka (Aoyama Gakuin U.), M. Ohno, M. Kokubun, M. Suzuki,
T. Takahashi (ISAS/JAXA), Y.E. Nakagawa, T. Tamagawa (RIKEN),
Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira 
(Hiroshima U.), S. Hong (Nihon U.), 
on behalf of the Suzaku WAM team, report:

The long, bright GRB 081224 (Fermi-GBM trigger #251846276; Colleen et
al., GCN 8725) triggered the Suzaku Wide-band All-sky Monitor (WAM)
 which covers an energy range of 50 keV - 5 MeV at 2008-12-24 21:17:55.214 UT (=T0).

The observed light curve shows a FRED-like peak structure
starting at T0-0.2s, ending at T0+19.8s with a duration (T90) of about 10.3 seconds.
The fluence in 100 - 1000 keV was 2.87(+0.09, -0.04) erg/cm^2.
The 1-s peak flux measured from T0+2s - T0+3s was 16.95(+0.91, -0.55) photons/cm^2/s in the same
 energy range.

Preliminary result shows that the time-averaged spectrum from
T0-0.2s to T0+19.8s is well fitted by a power-law with exponential cutoff model
  dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
  alpha       0.83(+0.27, -0.28), and
  Epeak       447(+57, -40) keV (chi^2/d.o.f. = 19/22).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB081226B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8740
SUBJECT: GRB 081226B: Swift XRT and UVOT upper limits
DATE:    08/12/27 10:02:56 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans (U. Leicester) and E.A. Hoversten (PSU) report on behalf of
the Swift team:

Swift observed the field of GRB 081226B (Mereghetti et al. GCN Circ
8734) for 8 ks, beginning 9.6 ks after the INTEGRAL trigger. The XRT
data (all in Photon Counting mode) contain no source in the INTEGRAL
error circle. A 3-sigma upper limit is 0.001 counts/sec which is 5.6e-14
erg cm^-2 s^-1 for a typical GRB spectrum.

Given the absence of an XRT position, the UVOT images were compared to
archival images from the Digitized Sky Survey.  No candidate afterglow
was found in the INTEGRAL error circle.  UVOT magnitude 3-sigma upper
limits are reported in the following table:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
WHITE     9744     22737    1414        > 22.24
v         9621     27619    1940        > 20.48
b         9720     21824    1414        > 21.06
u         9694     16082     352        > 20.34
uvw1     10019     15877     313        > 20.20
uvm2     15472     28224     787        > 20.75
uvw2     10812     23271     932        > 21.27

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.01 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).

This circular is an official product of the Swift XRT and UVOT teams.


GRB_name: GRB081221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8741
SUBJECT: VLA radio observation of GRB 081221
DATE:    08/12/27 20:13:00 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on
behalf of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward
GRB 081221 (GCN 8687) at a frequency of 8.46 GHz on 2008 Dec 27.14
UT. The GRB radio afterglow is undetected at 3-sigma level. However,
there is a 2.5 sigma source (97 +/- 38 uJy) at the Gemini optical
afterglow position reported by Tanvir et al. (GCN 8698).

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB081228A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8742
SUBJECT: GRB 081228: Swift detection of a burst
DATE:    08/12/28 01:33:10 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

K. L. Page (U Leicester), W. H. Baumgartner (GSFC/UMBC),
P. J. Brown (PSU), D. N. Burrows (PSU),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), C. B. Markwardt (CRESST/GSFC/UMD) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 01:17:40 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 081228 (trigger=338338).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 39.467, +30.843 which is 
   RA(J2000) = 02h 37m 52s
   Dec(J2000) = +30d 50' 33"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single peak
with a duration of about 2.5 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~0.5 sec after the trigger. 

The XRT began observing the field at 01:18:58.7 UT, 78.0 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 39.46043, 30.85393 which is equivalent
to:
   RA(J2000)  = 02h 37m 50.50s
   Dec(J2000) = +30d 51' 14.1"
with an uncertainty of 4.8 arcseconds (radius, 90% containment). This
location is 44 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
8.8e+20 cm^-2 (Kalberla et al. 2005). 

UVOT took a finding chart exposure of  37 seconds with the White filter
starting 82 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 25% of
the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
BAT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.16. 

Burst Advocate for this burst is K. L. Page (kpa AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB081228A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8743
SUBJECT: GRB 081228: TAROT Calern observatory optical observations
DATE:    08/12/28 02:01:57 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Gendre, B. (OAMP),
Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 081228 detected by SWIFT
(trigger 338338) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 24.7s after the GRB trigger
(6.1s after the notice). The elevation of the field decreased
from 24 degrees above horizon and weather conditions
were good.

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT in the XRT error box (Page et al.
GCNC 8742) with a limiting magnitude of:
t0+24.7s to t0+84.7s : R > 16.9

The second image is 30.0s exposure in tracking mode:
t0+91.8s to t0+121.8s : R > 17.4

We co-added a series of exposures:
t0+91.8s to t0+384.6s : R > 18.4

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon=148.4290 lat=-26.7069
and the galactic extinction in R band is 0.4 magnitude
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.


GRB_name: GRB081228A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8744
SUBJECT: GRB 081228: Enhanced Swift-XRT position
DATE:    08/12/28 03:20:28 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 27 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 081228, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 39.4616, +30.8526 which is equivalent
to:

RA (J2000): 02h 37m 50.77s
Dec (J2000): +30d 51' 09.5"

with an uncertainty of 2.9 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB081228A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8745
SUBJECT: GRB 081228: detection by GROND
DATE:    08/12/28 07:50:22 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 081228: detection by GROND 

P. Afonso (MPE), S. Klose (Tautenburg), T. Kruehler, (MPE), J. Greiner
(MPE), A. Updike (Clemson University), A. Kupcu-Yoldas(ESO), A. Yoldas 
(MPE), and G. Szokoly (EÃ¶tvÃ¶s Univ. Budapest) report on behalf of the 
GROND team: 


GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m ESO/MPI
telescope at La Silla Observatory (Chile) imaged the field of GRB 081228
(Swift trigger 338338, Page et al., GCN #8742) simultaneously in
g'r'i'z'JHK. 

Inside the enhanced XRT error circle (position, RA (J2000): 02h 37m 50.77s
Dec (J2000): +30d 51' 09.5"), reported by Goad et alia, GCN #8744, we
detect an object in the g'r'i'z' bands, but not in JHK. 

Observations started at 01h26 UT, 9 min after the burst. 

We used 4 images of 375 s exposure in g'r'i'z' and 120 images of 10s
exposure in JHK. The images midtimes for g'r'i'z' and JHK are respectively
02h23m59s and 02h24m20s UT, or 1h6m19s and 1h6m40s after the burst. 

Observations were done at high air mass and seeing bigger than 1''. 

The object is detected in the g'r'i'z' bands, implying a redshift smaller
than 3.5. The detection is fainter in the g' band. 

Preliminary VEGA magnitudes calibrated against USNO-B field stars and
upper limits are as follows: 

g' = 23.73 +/- 0.11
r' = 21.98 +/- 0.04
i' = 21.42 +/- 0.06
z' = 21.80 +/- 0.08
J > 19.6
H > 18.4
K > 17.6 

No correction for galactic extinction was done. 


GRB_name: GRB081228A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8746
SUBJECT: GRB 081228: Swift-XRT Team refined analysis
DATE:    08/12/28 10:16:19 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page & P.A. Evans (U. Leicester) report on behalf of the Swift-XRT 
team:

We have analysed the first 4.6 ks of XRT data obtained for GRB 081228 
(Page et al., GCN Circ. 8742), all of which was collected in Photon 
Counting mode. We have further refined the position given by Goad et al. 
in GCN Circ. 8744, and now find an astrometrically corrected X-ray 
position (using the XRT-UVOT alignment and matching UVOT field sources to 
the USNO-B1 catalogue) of

RA (J2000):   02 37 50.89
Dec (J2000): +30 51 09.1

with an uncertainty of 2.2 arcsec (radius, 90% confidence).

The data can be fitted with a single power-law with a decay of alpha = 1.4 
+/- 0.1, although there is some evidence for a flattening after about 8 
ks.

The spectrum of the first orbit of data can be modelled with a power-law 
of photon index Gamma = 1.5 +/- 0.4, absorbed by the Galactic column in 
this direction of 8.8x10^20 cm^-2. The upper limit on the total absorbing 
column is 4.7x10^21 cm^-2. The observed (unabsorbed) flux over this time 
(86-117 s after the trigger) is 1.23x10^-10 (1.38x10^-10) erg cm^-2 s^-1, 
corresponding to a counts to observed flux conversion of 5.1x10^-11 erg 
cm^-2 count^-1.

Taking into account the possible flattening of the decay at later times, 
the count rate at 24 hours is predicted to be between 4.5x10^-3 and 
2.7x10^-4 count s^-1 (observed flux between 2.3x10^-13 and 1.4x10^-14 erg 
cm^-2 s^-1).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB081228A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8747
SUBJECT: GRB 081228: Swift/UVOT  Upper Limits
DATE:    08/12/28 16:00:24 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W. Landsman (GSFC) and K. L. Page (U. Leicester) report on behalf of the 
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 081228 82s 
after the BAT trigger (Page et al., GCN 8742).
The exposure time was limited by observing constraints until about 1 
hour after the trigger.   We do not detect any source at the refined 
Swift XRT position (Page & Evans GCN 8746).   UVOT magnitude 3-sigma 
upper limits in a 5" aperture are reported in the following table:

Filter   T_start     Exp(s)  Mag (3-sigma upper limit)
------------------------------------------------------
white       82         37      > 20.0
white     4679        137      > 20.7
v         3653        197      > 19.3
b         4473        197      > 20.3
u         4268        197      > 20.0
uvw1      4063        197      > 20.0
uvm2      3858        197      > 20.0
uvw2      9102        886      > 20.9

The quoted upper limits have not been corrected for the expected 
Galactic extinction along the line of sight of E_(B-V) = 0.16 mag.   All 
photometry is on the UVOT photometric system described in Poole et al. 
(2008, MNRAS, 383, 627).


GRB_name: GRB081221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8748
SUBJECT: VLA radio detection of GRB 081221
DATE:    08/12/28 16:10:17 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on
behalf of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to re-observe the field of view toward
GRB 081221 (GCN 8687) at a frequency of 8.46 GHz on 2008 Dec 28.16
UT for a longer integration. The GRB radio afterglow is clearly
detected at the Gemini optical afterglow position (GCN 8698) with the
flux density of 167 +/- 27 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB081228A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8749
SUBJECT: GRB 081228, Swift-BAT refined analysis
DATE:    08/12/28 17:04:20 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm@nasa.gov>

C. B. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), W. H. Baumgartner 
(GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), K. McLean (GSFC/UMD), K. L. Page (U Leicester),
D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry 
downlink,
we report further analysis of Swift GRB 081228 (trigger #338338)
(Page, et al., GCN Circ. 8742).  The BAT ground-calculated position is
RA, Dec = 39.477, 30.833 deg which is
  RA(J2000)  =  02h 37m 54.4s
  Dec(J2000) = +30d 49' 57.3"
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 85%.

The mask-weighted light curve begins with a possible faint soft 20-second
precursor beginning at T-180 sec.  The main emission consists of a single
peak beginning at T-0.5 sec and lasting ~2.5 seconds. T90 (15-350 keV) is
3.0 +- 1.4 sec (estimated error including systematics). An observing 
constraint
caused the Swift spacecraft to slew away from the burst location at
~T+250 seconds, so no information about the burst is available after
~T+300 sec, when the burst was no longer in the field of view.

The time-averaged spectrum from T-0.1 to T+2.9 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.10 +- 0.31.  The fluence in the 15-150 keV band is 8.9 +- 1.8 x 10-8 
erg/cm2.
The 1-sec peak photon flux measured from T+0.87 sec in the 15-150 keV band
is 0.6 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

With a duration longer than 2 s and a soft spectrum, this burst is 
likely to
be in the "long" category.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/338338/BA/


GRB_name: GRB081226C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8750
SUBJECT: GRB 081226C: Fermi GBM detection
DATE:    08/12/29 15:22:32 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi (MPE) and S. McBreen (UCD/MPE) 
report on behalf of the Fermi GBM Team: 


"At 03:44:52.41 UT on 26 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081226C (trigger 251955893 / 081226156).
The on-ground calculated location, using the GBM trigger 
data, is RA = 189.4, DEC = 27.8 (J2000 degrees, 
equivalent to 12h 38m, 27d 48'), with an uncertainty 
of 3.6 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 54 degrees.

This long GRB consists of two main emission pulses plus
weak untriggered emission starting at about T0-45 s
and lasting about 25 s.
The total event duration (T90) is about 60 s (8-1000 keV).

The time-averaged spectrum from T0-3.6 s to T0+10.7 s is
best fit by a power law function with an
exponential high energy cutoff. The power law index is
-1.04 +/- 0.11 and the cutoff energy, parameterized as
Epeak, is 82 +/- 7 keV (chi squared 395 for 362 d.o.f.).
The time-averaged spectrum of the precursor from T0-48.6 s
to T0-28.2 s is also well fit by a power law function with an
exponential high energy cutoff. The power law index is
-1.14 +/- 0.23 and the cutoff energy, parameterized as Epeak,
is 71 +/- 11 keV (chi squared 370 for 363 d.o.f.).

The event fluence (8-1000 keV) from T0-3.6 s to T0+10.7 is
(2.32 +/- 0.24)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+6.6 s in the 8-1000 keV band
is 4.5 +/- 0.8 ph/s/cm^2.


The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081226B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8751
SUBJECT: GRB 081226B: Fermi GBM observation
DATE:    08/12/29 15:24:54 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi (MPE) and S. McBreen (UCD/MPE)
report on behalf of the Fermi GBM Team: 


"At 12:13:10.71 UT on 26 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081226B (trigger 251986391 / 081226509),
which was also detected by INTEGRAL (Mereghetti et al. 2008, GCN 8734)
The GBM on-ground location is consistent with the INTEGRAL position.
 
The angle from the Fermi LAT boresight is 22 degrees.

The GBM light curve consists of a single pulse
with a duration (T90) of about 0.35 s (8-1000 keV). 
The time-averaged spectrum from T0-0.08 s to T0+0.12 s is
well fit by a power law function with an exponential
high energy cutoff. The power law index is -0.51 +/- 0.17 and
the cutoff energy, parameterized as Epeak, is 530 +/- 110 keV
(chi squared 300 for 324 d.o.f.).
A Band function fits the spectrum equally well with
Epeak = 300 +/- 110 keV, alpha = -0.2 +/- 0.3 and
beta = -1.82 +/- 0.23 (chi squared 292 for 323 d.o.f.).

The event fluence (8-1000 keV) in this time interval for
the power law function with exponential cutoff is 
(6.1 +/- 0.5)E-07 erg/cm^2. The 64-ms peak photon flux
measured starting from T0-0.01 s in the 8-1000 keV band
is 17.7 +/- 1.5 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081228A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8752
SUBJECT: GRB 081228: GROND confirmation of the optical/NIR afterglow 
DATE:    08/12/29 18:29:33 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

P. Afonso, T. Kruehler, J. Greiner (all MPE), and S. Klose 
(Tautenburg) report on behalf of the GROND team:

We report on further analysis of the GROND data of the optical 
afterglow candidate of GRB 081228 (Swift trigger 338338, Page et al., 
GCN #8742).

The optical/NIR source inside the XRT errorcircle, previously reported 
in GCN #8745 by P. Afonso et al., is found to be clearly variable. The 
position of the afterglow is:

RA(J2000): 02:37:50.94
DEC(J2000): +30:51:10.5

with uncertainties of 0.5" in each coordinate.

Preliminary photometry yields the following r' band magnitudes, 
uncorrected for Galactic foreground reddening:

T_mid[s]  Exp[s] Mag     MagErr
-------------------------------
449       35     19.81   0.04
667       35     20.25   0.04
872       35     20.59   0.06
1380      115    21.21   0.05
1581      115    21.34   0.05
3308      375    22.09   0.08

The quoted error is statistical only. There is an additional 
systematic error in the absolute calibration using the GROND zeropoint 
which is expected to be in the 0.2 mag range. As the GROND photometric 
system is based on the SDSS in g'r'i'z' these values are AB magnitudes.

The complete light curve obtained during the first night post burst 
can be reasonably well described with a power law of index 1.1 +- 0.2.

A broad band SED from g' to K was constructed using data obtained 
simultaneously at a midtime of 1500 s after the trigger. After 
correcting for a Galactic foreground extinction corresponding to a 
reddening of E_(B-V)= 0.16 (Schlegel et al. 1998), the r' to K band 
SED is well described with a power law of spectral index beta = 0.85 
+- 0.15.

We tentatively associate the large, foreground extinction corrected 
g'-r' color of around 1.4 mag with Ly-alpha absorption in the host at 
a redshift of 3.8 +- 0.4. This photometric redshift estimate has been 
obtained using hyperZ (Bolzonella et al. 2000). We caution, however, 
that this might be subject to changes due to a future improved 
calibration.


GRB_name: GRB081230A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8753
SUBJECT: GRB 081230: Swift detection of a burst
DATE:    08/12/30 21:02:09 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

V. La Parola (INAF-IASFPA), S. D. Barthelmy (GSFC), P. J. Brown (PSU),
J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
J. A. Kennea (PSU), W.B Landsman (GSFC), V. Mangano (INAF-IASFPA),
J. P. Osborne (U Leicester), K. L. Page (U Leicester),
B. Sbarufatti (INAF-IASFPA) and T. N. Ukwatta (GSFC/GWU) report on
behalf of the Swift Team:

At 20:36:12 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 081230 (trigger=338633).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 37.315, -25.142 which is 
   RA(J2000) = 02h 29m 16s
   Dec(J2000) = -25d 08' 29"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single peak
with a duration of about 50 sec.  The peak count rate
was ~600 counts/sec (15-350 keV), at ~50 sec after the trigger. 

The XRT began observing the field at 20:38:16.7 UT, 124.1 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 37.33148,
-25.14645 which is equivalent to:
   RA(J2000)  = 02h 29m 19.56s
   Dec(J2000) = -25d 08' 47.2"
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 56 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.68e+20
cm^-2, Kalberla et al. 2005), with an excess column of 3.2
(+2.81/-2.34) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 250 seconds with the U filter starting
132 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the
XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The
8'x8' region for the list of sources generated on-board covers 100% of the XRT
error circle. The list of sources is typically complete to about 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.01. 

Burst Advocate for this burst is V. La Parola (laparola AT ifc.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB081230A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8754
SUBJECT: GRB 081230: ROTSE-III Detection of Optical Counterpart 
DATE:    08/12/30 21:20:41 GMT
FROM:    Fang Yuan at ROTSE  <yuanfang@umich.edu>

F. Yuan (U Mich), E.S. Rykoff (UCSB), report on behalf of the ROTSE  
collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,  
responded to GRB 081230 (Swift trigger 338633). The first image was at  
20:47:53.4 UT, 700.8 s after the burst (8.4 s after the GCN notice  
time). The unfiltered images are calibrated relative to USNO A2.0. We  
detect a 19.1 magnitude, steady source in the XRT error box with  
coordinates:

      02:29:19.35      -25:08:49.22    (J2000), with positional  
uncertainty of 1" or better

start UT     mag     mlim(of image)
----------------------------------
20:49:23.0     19.1     19.2


This source is not visible in DSS (second epoch), 2MASS or the  
MPChecker database.

A jpeg image is available at http://www.rotse.net/images/gsb338633_3c021-030_key.jpg

Continuing observations are in progress. 


GRB_name: GRB081230A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8755
SUBJECT: GRB 081230: Swift/UVOT Detection of an Optical Afterglow 
DATE:    08/12/30 21:21:51 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/GSFC/USRA), P. J. Brown (PSU), and V. La Parola
(INAF-IASFPA) report on the behalf of the Swift UVOT team:

        The Swift/UVOT detects a faint source in the XRT error circle
for GRB 081230 (La Parola, et al. 2008, GCN Circ. 8753).  The source
has a preliminary position of

     RA (J2000)   02:29:19.48  =   37.33117 (deg)
     Dec (J2000) -25:08:48.5   =  -25.14682 (deg)

and a preliminary u-band magnitude of u = 20.6 +/- 0.3 mag in a 250 s
exposure starting 131 s after the BAT trigger.  The quoted magnitude
has not been corrected for the expected Galactic extinction along the
line of sight corresponding to a reddening of E_{B-V} = 0.01 mag
(Schlegel, et al., 1998, ApJS, 500, 525).  The photometry is on the
UVOT flight system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB081230A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8756
SUBJECT: GRB 081230: Enhanced Swift-XRT position
DATE:    08/12/31 01:11:24 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1640 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 081230, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 37.3314, -25.1477 which is equivalent
to:

RA (J2000): 02h 29m 19.53s
Dec (J2000): -25d 08' 51.8"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB081230A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8757
SUBJECT: GRB 081230  Swift/UVOT Observations
DATE:    08/12/31 12:31:41 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (MSSL-UCL) and V. La Parola (INAF-IASFPA) report on behalf  
of the Swift/UVOT team:

The Swift/UVOT began observerving the field of GRB 081230 132 s
after the BAT trigger ( La Parola et al., GCN Circ. 8753). We detect the
optical afterglow in the white, v, b and u filters at the position:

RA(J2000)  = 02:29:19.467
DEC(J2000) = -25:08:51.0

with an estimated uncertainty of 0.9 arcsec (radius, 90% confidence).
This position is consistent with the UVOT-enhanced XRT position  
(Osborne et al., GCN 8756)
and the optical afterglow position reported by ROTSE-III (Yuan et al.,  
GCN 8754).

The magnitudes and 3 sigma upper limits are reported below:

Filter    T_start (s) T_stop  Exposure    Mag/3sig UL
------------------------------------------------------------
white       4060  4210   147   20.45 +/- 0.35
v          587    607     19     18.30 +/- 0.48
b          388    408     19     18.92 +/- 0.36
u          132    382     246   20.28 +/- 0.38
u          511    531  19     19.04 +/- 0.52
uvw1  487    5854   435   > 21.23
uvm2       462    5649   255   > 20.95
uvw2       414     6575   353   > 21.44
------------------------------------------------------------

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.01 mag (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT flight system
described in Poole et al. (2008, MNRAS, 383,627).


GRB_name: GRB081230A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8758
SUBJECT: GRB081230: Swift-XRT refined analysis
DATE:    08/12/31 14:23:44 GMT
FROM:    Valentina La Parola at INAF-IASPA  <laparola@ifc.inaf.it>

V. La Parola, B. Sbarufatti, V. Mangano (INAF-IASF Pa)
report on behalf of the Swift XRT team:


We have analysed the first 35 ks of XRT observations for GRB 081230
(La Parola et al. GCN Circ 8753), with an exposure time of 104 s in WT mode and
11.4 ks in PC mode. The astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources to
the USNO-B1 catalogue) is RA, Dec = 37.3314 -25.1477, corresponding to:

RA (J2000): 02h 29m 19.53s
Dec (J2000): -25d 08' 51.8


with an uncertainty of 1.8 arcsec (radius, 90% confidence, Osborne et al.
GCN Circ 8756).

The lightcurve can be fitted with a broken power-law with the following
parameters:
alpha1=-6.910+/-0.007
T_break=298+/-9
alpha2=-0.62+/-0.5
There is evidence for a late flare a peaking at 5000s.

The spectrum of the data collected in WT mode can be fitted with a powerlaw
with photon index Gamma = 1.96 +/- 0.11, absorbed by the Galactic column in
this direction of 1.7x10^20 cm^-2, plus an intrinsic column of
(6.4+/-2.2)x10^20 cm^-2. The observed (unabsorbed) flux over this time
is 1.03x10^-9 (1.3x10^-9) erg cm^-2 s^-1,
corresponding to a counts to observed flux conversion of 4.1x10^-11 erg
cm^-2 count^-1.
The spectrum of the data collected in PC mode can be fitted with a powerlaw
with photon index Gamma = 2.14 (+0.10,-0.20), with an intrinsic column of
(5.3 [+2.2,-3.7])x10^20 cm^-2. The observed (unabsorbed) flux over this time
is 2.1x10^-12 (2.7x10^-9) erg cm^-2 s^-1,

With the present decay law, the count rate at 24 hours is predicted to be
1.1x10^-2 c/s (corresponding to an observed flux of 3.7x10^-13 erg cm^-2 s^-1)

This circular is an official product of the Swift-XRT team.




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GRB_name: GRB081230A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8759
SUBJECT: GRB 081230, Swift-BAT refined analysis
DATE:    08/12/31 15:07:48 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm@nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), V. La Parola (INAF-IASFPA), C. B. Markwardt 
(GSFC/UMD),
K. McLean (GSFC/UMD), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):

Using the data set from T-300 to T+1197 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 081230 (trigger #338633)
(La Parola, et al., GCN Circ. 8753).  The BAT ground-calculated position is
RA, Dec = 37.330, -25.145 deg which is 
   RA(J2000)  =  02h 29m 19.2s 
   Dec(J2000) = -25d 08' 42.6" 
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted light curve consists of a series of overlapping peaks ranging
from T+5 sec to T+70 sec, with the strongest emission at ~T+50 seconds.
T90 (15-350 keV) is 60.7 +- 13.8 sec (estimated error including systematics).
 
The time-averaged spectrum from T-14.4 to T+62.4 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.97 +- 0.16.  The fluence in the 15-150 keV band is 8.2 +- 0.8 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+46.63 sec in the 15-150 keV band
is 0.7 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/338633/BA/


GRB_name: GRB081230A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8760
SUBJECT: GRB 081230: GROND confirmation of the afterglow
DATE:    09/01/01 15:20:21 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 081230: GROND confirmation of the afterglow 


P. Afonso (MPE), C. Clemens (MPE), S. Klose (Tautenburg), J. Greiner
(MPE) and G. Szokoly (Eotvos Univ. Budapest) report on behalf of the
GROND team: 

GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m ESO/MPI
telescope at La Silla Observatory (Chile) imaged the field of GRB 081230
(Swift trigger 338633, La Parola et al., GCN #8753) simultaneously in
g'r'i'z'JHK bands 

We detected and confirm the afterglow candidate in all bands, at the 
position: 

RA(J2000): 02:29:19.51
DEC(J2000): -25:08:49.95 

with uncertainties of 0.5" in each coordinate. 

This position is compatible with UVOT (Oates et alia, GCN #8757) and
ROTSE-III (Yuan et alia, GCN #8754) reported positions. 

Observations started on Dec. 31 at 00h48 UT, 15123 seconds, or ~ 4.2 hours
after the burst. 

We used 4 images of 375 s exposure in g'r'i'z' and 120 images of 10s
exposure in JHK, for each epoch. 

The images mid time for the 1st epoch is 5.99h (or 21564 seconds) after the 
burst. Observations were done at an average air mass = 1.128 and seeing ~ 
1.5''. 

We took a 2nd epoch on January 1st, 2009, starting at 03h21 UT. 

The images mid time for the 2nd epoch is 30.99h (or 111564 seconds) after 
the burst. Observations were done at an average air mass = 1.334 and seeing 
~ 1.3''. 

The preliminary data for the 2nd epoch clearly confirms the fading of the 
afterglow: 

We present preliminary photometric results for g'r'i'z'. The AB magnitudes, 
using GROND zero points are as follows: 

     1st epoch       2nd epoch 

g' = 21.32 +- 0.02   23.67 +- 0.08
r' = 20.96 +- 0.01   23.07 +- 0.06
i' = 20.74 +- 0.02   22.79 +- 0.09
z' = 20.66 +- 0.03   22.84 +- 0.17 

No correction for galactic extinction was done. 

The quoted error is statistical only. There is an additional
systematic error in the absolute calibration using the GROND zeropoints
which is expected to be in the 0.2 mag range. 

Further data analysis is ongoing for JHK - the aftegrlow being clearly 
visible on the first epoch, but not on the 2nd. 

  


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8761
SUBJECT: GRB 090102: TAROT Calern observatory optical observations
DATE:    09/01/02 03:08:29 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Gendre, B. (LAM_OAMP),
  Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 090102 detected by SWIFT
(trigger 338895) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 40.8s after the GRB trigger
(6.8s after the notice). The elevation of the field decreased from
from 68 degrees above horizon and weather conditions
were good.

We detect a new fading source in the error box given by SWIFT
at the following position (+/- 1 arcsec):

RA(J2000) = 08h 32m 38.1s
DEC(J2000) +33d 11' 45.3"

OT was R~15.3 at about 100s after GRB.

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon=189.8804 lat=+34.6651
and the galactic extinction in R band is 0.1 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.


GRB_name: GRB090102A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8762
SUBJECT: GRB 090102: Swift detection of a burst with an optical counterpart
DATE:    09/01/02 03:08:41 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

V. Mangano (INAF-IASFPA), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC),
E. A. Hoversten (PSU), J. A. Kennea (PSU),
V. La Parola (INAF-IASFPA), W.B Landsman (GSFC),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC) and
B. Sbarufatti (INAF-IASFPA) report on behalf of the Swift Team:

At 02:55:45 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090102 (trigger=338895).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 128.259, +33.092 which is 
   RA(J2000) = 08h 33m 02s
   Dec(J2000) = +33d 05' 29"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 30 sec starting about 15 sec before
the trigger.  The peak count rate was ~7000 counts/sec (15-350 keV),
at ~2 sec after the trigger. 

The XRT began observing the field at 03:02:13.1 UT, 387.2 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 128.2423, +33.1142 which is equivalent to:
   RA(J2000)  = 08h 32m 58.15s
   Dec(J2000) = +33d 06' 51.1"
with an uncertainty of 6.1 arcseconds (radius, 90% containment). This
location is 94 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 


UVOT took a finding chart exposure of nominal 150 seconds with the White filter
starting 395 seconds after the BAT trigger. There is a candidate afterglow in
the list of sources generated on-board at
  RA(J2000)  = 08:32:58.54 = 128.24391
  DEC(J2000) = +33:06:51.2  = 33.11421
with a 90%-confidence error radius of about 1.10 arc sec. This position is 4.8
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.11. No correction has been made for the expected extinction corresponding to
E(B-V) of 0.05. 




Burst Advocate for this burst is V. Mangano (vanessa AT ifc.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8763
SUBJECT: GRB 090102: REM observations of a bright afterglow
DATE:    09/01/02 03:30:14 GMT
FROM:    Stefano Covino at Brera Astronomical Observatory  <stefano.covino@gmail.com>

S. Covino, P. D'Avanzo, L.A. Antonelli, D. Malesani, D. Fugazza, L.   
Calzoletti,  S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini,   
V. D'Elia,  F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C.  
Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A.  
Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella,   
G. Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, F.  
Vitali report on behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed  
automatically the field of the GRB 090102 (Mangano et al. GCN8762)  
starting about 35s after the burst (26s after the alert).  We detect  
a bright object in
our first R- and H-band images consistent with the optical  
counterpart identified by UVOT (Mangano et al. GCN8762) and TAROT  
(Klotz et al. GCN 8761).

The object is approximately R~14.2 (relative to nearby USNO-B1 stars)  
and H~12 (relative to nearby 2MASS stars)
at about 1min after the burst.

Further observations are in progress


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8764
SUBJECT: GRB 090102: TAROT Calern observatory optical light curve
DATE:    09/01/02 05:14:46 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Gendre, B. (OAMP),
Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We analyzed images of GRB 090102 detected by SWIFT
(trigger 338895) with the TAROT at the Calern
observatory, France.

In our previous GCN Circ. (9761) we made a mistake
in the celestial coordinates of the optical afterglow.
TAROT position is compatible with UVOT (Mangano et
al. GCNC 8762).

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39)
and we detect the growth of the optical light curve
that culminates at t0+60s (+/- 3s) with a brightness R=13.4
(i.e. ~40s after the end of the gamma activity).
We calibrated magnitudes in R band using
NOMAD1 1231-0209716 (R=13.31).

After t0+60s, the decay of the afteglow is classic with
a decay of alpha=1.6 +/- 0.2. Hereafter, TAROT Calern
data (tstart and tend are expressed in seconds after
the BAT trigger t0):

tstart tend  R      dR
  40.8  46.8  14.3   0.2
  46.8  52.8  13.6   0.1
  52.8  58.8  13.4   0.1
  58.8  64.8  13.4   0.1
  64.8  70.8  13.5   0.1
  70.8  76.8  13.7   0.1
  76.8  82.8  13.7   0.1
  82.8  88.8  14.0   0.1
  88.8  94.8  14.1   0.1
  94.8 100.8  14.3   0.1
107.6 137.6  14.4   0.2
144.6 174.6  14.9   0.2
181.6 211.6  15.5   0.3

Further observations are in progress


GRB_name: GRB090102A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8765
SUBJECT: GRB 090102: Enhanced Swift-XRT position
DATE:    09/01/02 07:31:44 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1798 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 090102, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 128.2442, +33.1145 which is equivalent
to:

RA (J2000): 08h 32m 58.60s
Dec (J2000): +33d 06' 52.1"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8766
SUBJECT: GRB 090102: NOT redshift
DATE:    09/01/02 09:29:37 GMT
FROM:    Pall Jakobsson at U Hertfordshire  <P.Jakobsson@herts.ac.uk>

Antonio de Ugarte Postigo (ESO), Pall Jakobsson (U. Iceland), 
Daniele Malesani, Johan P. U. Fynbo (DARK/NBI), Elaine Simpson 
and Susana Barros (Queen's University Belfast) report:

We observed the field of GRB 090102 (Mangano et al., GCN 8762) 
with the NOT/ALFOSC starting on Jan 2 at 03:33 (38 minutes after 
the burst onset). The optical afterglow detected by Klotz et al.
(GCN 8761) and Mangano et al. is detected with R ~ 19.6 (based on 
unfiltered images) at the following coordinates (J2000, 0.5" error):

RA: 08:32:58.54
Dec.: +33:06:51.1

A 45-min low-resolution spectrum was also obained (2 hours post 
burst). A firm upper limit of z < 2.1 can be placed on the 
redshift of GRB 090102 from the lack of Ly-alpha forest lines in 
the spectrum of the afterglow.

The spectrum also displays several metal lines, including Fe II, 
Mg II, Mg I, Al II, Al III and C IV, at a redshift of z = 1.547.
No other significant lines are visible. We therefore conclude
that z = 1.547 is the redshift of GRB 090102.


GRB_name: GRB090102A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8767
SUBJECT: GRB 090102: Swift XRT refined analysis
DATE:    09/01/02 16:30:08 GMT
FROM:    Vanessa Mangano at INAF-IASFPA  <vanessa@ifc.inaf.it>

V. Mangano, V. La Parola, B. Sbarufatti (INAF-IASF PA)
report of behalf the Swift XRT team:

We have analysed 6 orbits of Swift XRT data of GRB 090102
(Mangano et al. GCN Circ. 8762), consisting of 241 s in WT mode
and 6.7 ks in PC mode.

The XRT observation started 393 s after the trigger.
The XRT light curve is well fitted by a single power-law
with slope -1.32 +/- 0.01, and if decaying at this rate
the source will reach a count rate level of 0.02 counts/s
after one day.

The WT spectrum is well fitted by an absorbed power-law
with photon index 1.7 +/- 0.1, Galactic NH = 4.0e20 cm^-2
(Kalberla et al. 2005) and intrinsic absorption column of
(3.8 +/- 2.0) e21 cm^-2 at the measured redshift z = 1.547
(De Ugarte Postigo et al. GCN Circ. 8766).
The average observed [unabsorbed] flux during the WT observation
is 6.2e-10 [7.2e-10] erg cm^-2 s^-1.

The PC spectrum, extracted from about T+630 s to T+25 ks,
is also well fitted by an absorbed power law with photon
index 1.8 +/- 0.1, Galactic NH = 4.0e20 cm^-2 and
and intrinsic NH = (7.0 +/- 2.0) e21 cm^-2 at z = 1.547.
The average observed [unabsorbed] flux during the PC observation is
2.8e-11 [3.5e-11] erg cm^-2 s^-1.

The rate to flux conversion factor is 1.3e-10 erg cm^-2 counts^-1.

This is an official product of the Swift XRT team.


GRB_name: GRB090102A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8768
SUBJECT: GRB 090102: Swift burst of interest 
DATE:    09/01/02 16:34:41 GMT
FROM:    Vanessa Mangano at INAF-IASFPA  <vanessa@ifc.inaf.it>

V. Mangano (INAF-IASF PA), S. Bathelemy (GSFC), P. A. Curran
(UCL-MSSL), N. Gehrels (NASA/GSFC), D. Burrows (PSU)
report on behalf the Swift team:

Based on its bright multiwavelength emission and good sun angle,
the Swift team declares GRB 090102 to be a burst of interest
to be followed by Swift to late time.  We encourage ground
based follow-ups and cooperation of the scientific community in
revising Swift observation plans according to results.  Please post
your results / plans or send us informal information.


GRB_name: GRB090102A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8769
SUBJECT: GRB 090102: Swift-BAT refined analysis
DATE:    09/01/02 16:35:19 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), V. Mangano (INAF-IASFPA), C. B. Markwardt (GSFC/UMD),
D. M. Palmer (LANL), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090102 (trigger #338895)
(Mangano, et al., GCN Circ. 8762).  The BAT ground-calculated position is
RA, Dec = 128.248, 33.107 deg, which is 
   RA(J2000)  =  08h 32m 59.5s 
   Dec(J2000) = +33d 06' 25.7" 
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 6%.
 
The mask-weighted light curve shows approximately 4 overlapping peaks
starting at ~T-14 sec, peaking at ~T+2 sec, and ending at ~T+15 sec.
T90 (15-350 keV) is 27.0 +- 2.2 sec (estimated error including systematics).
 
The time-averaged spectrum from T-13.9 to T+18.7 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.36 +- 0.08.  The fluence in the 15-150 keV band is 6.8 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.68 sec in the 15-150 keV band
is 5.5 +- 0.8 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/338895/BA/


GRB_name: GRB090102A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8770
SUBJECT: Swift UVOT observations of GRB 090102
DATE:    09/01/02 17:15:34 GMT
FROM:    Peter Curran at MSSL  <pac@mssl.ucl.ac.uk>

P.A. Curran (UCL-MSSL), V. Mangano (INAF-IASF PA) and S.T. Holland
(GSFC) on behalf of the Swift/UVOT team.


The Swift Ultra-Violet/Optical Telescope (UVOT) began settled 
observations of the Swift localised GRB 090102 (#338895; Mangano et al., 
GCN 8762) ~400 seconds after the BAT trigger.

An afterglow, consistent with the enhanced XRT position (Beardmore et 
al., GCN 8765) and with the afterglow candidate of Klotz et al. (GCN 
8761), is detected at the position reported by  Mangano et al. (GCN 
8762). The source is detected in the initial optical observations but 
quickly fades (with alpha ~ 0.9 +/- 0.2 in white filter) below detection 
limits. The initial magnitudes (or 3 sigma limits) are:


Filter  t_mid(s)  Exp(s)  Mag

wh      470.      147.    18.04 +/- 0.04
v       382.      10.     17.02 +/- 0.29
b       660.      19.     18.35 +/- 0.27
u       635.      19.     17.89 +/- 0.26
uvw1    3547.     255.    >19.99
uvm2    6278.     197.    >19.67
uvw2    1035.     388.    >20.45

The detection in u along with the limits in uvw1 and bluer is consistent
with a redshift of approximately ~1.8 < z < ~2.5 and with the
spectroscopic redshift suggested by de Ugarte Postigo et al. (GCN 8766).

The values quoted above are in the UVOT photometric system (Poole et al.
2008, MNRAS, 383, 627).  They are not corrected for the expected
Galactic extinction corresponding to a reddening of E(B-V)=0.047 mag in
the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8771
SUBJECT: GRB 090102: GROND observations of the optical afterglow
DATE:    09/01/02 23:59:05 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 090102: GROND observations of the optical afterglow 


P. Afonso, T. Kruehler (both MPE Garching), S. Klose (TLS Tautenburg), and 
J. Greiner (MPE Garching) report on behalf of the GROND team: 


GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m ESO/MPI 
telescope at La Silla Observatory (Chile),started observations of the field 
of GRB 090102 (Mangano et al. 2008, GCN #8762) in g'r'i'z'JHK at 05:25 UTC, 
2.50 h after the burst. 

Preliminary photometry yields the following r' band magnitudes of the 
optical afterglow (Klotz et al., GCN #8761, and also GCNs #8762, #8763, 
#8764, #8766 and #8770), calibrated against SDSS field stars. 

T_mid[s]  Exp[s] AB Mag  MagErr
 -------------------------------
9042      66     20.58   0.05
9158      66     20.59   0.04
9265      66     20.58   0.03
9373      66     20.59   0.06
9515      115    20.59   0.04
9711      115    20.65   0.02
9903      115    20.67   0.02
10091     115    20.66   0.03
10423     375    20.70   0.02
10868     375    20.78   0.02
11320     375    20.79   0.02
11780     375    20.86   0.02 

The quoted error is statistical only. There is an additional systematic 
error in the absolute calibration using SDSS field stars which is expected 
to be in the 0.05 mag range. 

In this time interval, the light curve is well described with a single power 
law of index 1.0 +/- 0.1, compatible with the value reported by Curran et 
al. (GCN #8770). Comparing against the early TAROT data (Klotz et al., GCN 
#8764), this indicates a flattening of the light curve. If the afterglow 
continues to decline with this power law, we predict r' band magnitudes of 
~23.1 at 1 day and ~24.3 at 3 days after the burst. 

After correcting for a Galactic foreground extinction corresponding to a 
reddening of E_(B-V)=0.05 (Schlegel et al. 1998), the g' to K band SED is 
well described with a power law of spectral index beta = 1.0 +- 0.2. 


GRB_name: GRB090102A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8772
SUBJECT: GRB 090102 Observations from IAC80
DATE:    09/01/03 01:31:48 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (ESO), L. Blanco (IAC)
A.J. Castro-Tirado (IAA-CSIC), report on behalf
of a larger collaboration:

We have observed the field of GRB090102 (Mangano et al.,
GCN 8762) from the IAC80 telescope at Izaa Observatory in
Tenerife (Spain). A 6x300s combined exposure with mean
epoch 2.92 Jan 2009 (19.2h after the burst) shows the afterglow
(Klotz et al., GCN 8761) with R=22.6+/-0.3, as compared to
stars of the UNSO-B1.0. This is consistent with the prediction
of Afonso et al. (GCN 8771) for day 1.


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8773
SUBJECT: GRB 090102: P60 Imaging and P200 Spectroscopy
DATE:    09/01/03 01:55:08 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko (UC Berkeley), A. Rau and M. Salvato (Caltech) report on
behalf of a larger collaboration:

We have imaged the field of GRB090102 (Mangano et al., GCN 8762) with the
automated Palomar 60-inch telescope beginning at 03:46 on 2 Jan 2008 UT (~
50 min after the burst).  Observations were taken in the R, i', and g'
filters and continued throughout the night until sunrise roughly 10 hours
later.

The optical afterglow (Klotz et al., GCN 8761, Covino et al., GCN 8763) is
well detected in all three filters.  All three bands exhibit a relatively
smooth power-law decay with index ~ 0.9, consistent with the value
reported by Afonso et al. (GCN 8771).  We report here the following subset
of our R-band observations:

Tmid (s)   Texp (s)   Mag    Err
--------------------------------------
3190.2     120.0      19.75  0.13
5266.2     120.0      20.02  0.06
7704.3     120.0      20.41  0.07
9973.9     120.0      20.56  0.07
11911.5    120.0      20.78  0.08
14068.6    120.0      21.01  0.09
16144.7    120.0      21.09  0.09
18522.6    600.0      21.23  0.06
20631.5    600.0      21.42  0.06
22756.7    600.0      21.58  0.07
24832.6    600.0      21.86  0.08
27994.7   1200.0      21.72  0.05
32188.5   1200.0      22.02  0.06
36411.3   1200.0      21.93  0.11

Photometric calibration was performed relative to the SDSS DR7, with
photometric transformations from Jordi, Grebel, & Ammons (A&A, 460, 2006).

In addition, we have obtained a single 1800 s spectrum of the afterglow
with the Double Beam Spectrograph mounted on the Palomar 200" Hale
telescope at a mean epoch of Jan 2.22.  The spectrograph was configured to
provide wavelength coverage from the atmospheric cutoff to ~ 8000 A.  We
confirm the results of de Ugarte Postigo (GCN 8766), finding a single
strong absorption system at z = 1.546.  Given the lack of strong
Ly-alpha absorption, we place a slightly stricter limit on the host
redshift of z < 1.9.


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8774
SUBJECT: GRB 090102:  Hobby-Eberly Telescope Spectroscopy 
DATE:    09/01/03 07:13:58 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara and D. B. Fox (Penn State) report:

"Starting on 2009 January 2.24 UT we used the Marcario LRS spectrograph
on the Hobby-Eberly Telescope (R ~ 230) to obtain a 1000s spectrum of
the optical afterglow of GRB 090102 (Mangano et al., GCN 8762, Covino
et al., GCN 8763).
The spectrum covers the wavelength range 4200 to 10,000 Angstrom.
Unfortunately the data were taken under bad seeing conditions and the
average S/N is ~5.

Based on a preliminary calibration we detect some absorption features which
we identify as the MgII doublet (2796,2803) and MgI(2856) at redshift z 
= 1.55.

This value is consistent with the redshift reported by de Ugarte Postigo 
et al.
(GCN 8766) and Cenko et al. (GCN 8773).

We thank the HET staff for performing this observation, in particular
John Caldwell."


GRB_name: GRB081229A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8775
SUBJECT: GRB 081229: Fermi GBM detection
DATE:    09/01/03 10:00:27 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

Sheila McBreen (UCD/MPE) and Elisabetta Bissaldi (MPE)
report on behalf of the Fermi GBM Team:

"At 04:29:01.88 UT on 29 January 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located a short burst GRB 081229 (trigger 252217742 /
081229187).

The on-ground calculated location, using the GBM trigger
data, is RA = 170.5, DEC = 55.1 (J2000 degrees,
equivalent to 11 h 22 m, 55 d 06 '), with an uncertainty
of 8 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 44 degrees.

The GBM light curve consists of one pulse
with a duration of about 0.5 s (8-1000 keV).
The time-averaged spectrum from T0-0.106 s to T0+0.214 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.42 +/- 0.18 and
the cutoff energy, parameterized as Epeak, is 807 +/- 186 keV
(chi squared 437 for 485 d.o.f.).

A Band function fits the spectrum equally well with
Epeak = 585  +/- 188 keV, alpha=-0.27 +/- 0.27
and beta = -2.0 +/- 0.3 (chi squared 429 for 484 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(8.7 +/- 0.8)E-7 erg/cm^2. The 64-ms peak photon flux measured
starting from T0-0.042 s  using the Band model in the 8-1000 keV band
is 10.7 +/- 1.5 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090102A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8776
SUBJECT: Konus-Wind observation of GRB 090102
DATE:    09/01/03 12:32:25 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The long GRB 090102 (Swift-BAT trigger #338895: Mangano et al., GCN 
8762; Sakamoto et al., GCN 8769) triggered Konus-Wind at T0=10536.283 s 
UT (02:55:36.283).

The burst light curve shows a multipeaked structure with a duration of 
~30 s.

As observed by Konus-Wind the burst
had a fluence of 3.09(-0.25, +0.29)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+12.016 s
of 5.10(-0.72, +0.74)x10^-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+33.024 s) can be fitted (in the 20 keV - 2 MeV
range) by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.86(-0.13, +0.14),
and Ep = 451(-58, 73) keV (chi2 = 48.8/65 dof).
Fitting by GRB (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy
photon index: beta < -2.73 (chi2 = 68.8/64 dof).

All the quoted errors are at the 90% confidence level.

Assuming z = 1.547 (de Ugarte Postigo et al., GCN 8766)
and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27,
Omega_\Lambda = 0.73, the isotropic energy release E_iso ~1.9x10^53 erg,
the peak luminosity (L_iso)_max ~ 7.8x10^52 erg/s, and Ep_rest ~1100keV.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB090102_T10536/


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8778
SUBJECT: GRB 090102: GRT Optical Observation
DATE:    09/01/04 17:13:41 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <takanori.sakamoto-1@nasa.gov>

T. Sakamoto (UMBC/GSFC), D. Donato (ORAU/GSFC), N. Gehrels (GSFC),  
T. Okajima (JHU/GSFC), T. N. Ukwatta (GWU/GSFC), Y. Urata (Saitama U),  
C. Wallace (FGCU) 
  
We observed the field of GRB 090102 detected by Swift (trigger #338895;  
Mangano et al., GCN #8762) with the 14-inch Goddard Robotic Telescope (GRT)  
located at the Goddard Geophysical and Astronomical Observatory  
(http://cddisa.gsfc.nasa.gov/ggao/).   
 
Ten set of 5 sec and five set of 10 sec and 30 sec exposures were taken in  
the R filter starting from Jan. 2 03:11:58 (UT) about 16.2 min after  
the trigger.  We do not detect the optical afterglow (Klotz et al.,  
GCN #8761, Mangano et al., GCN #8762) both in the individual  
images and the combined image.  The estimated three sigma upper limit  
of the combined image (total exposure of 250 sec) is ~17.9 mag using 
the USNO-B1 catalog. 


GRB_name: GRB090102A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8779
SUBJECT: VLA radio upper limit on GRB 090102
DATE:    09/01/04 19:25:06 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on
behalf of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward
GRB 090102 (GCN 8762) at a frequency of 8.46 GHz on 2009 Jan 03.35
UT. The GRB radio afterglow is undetected at 3-sigma level. The
flux density at the Swift UVOT afterglow position (GCB 8762) is
91 +/- 49 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8780
SUBJECT: GRB 090102: optical decay
DATE:    09/01/05 12:15:18 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@astro.ku.dk>

D. Malesani, J. P. U. Fynbo (DARK/NBI), A. de Ugarte Postigo (ESO), J. 
Gorosabel (IAA/CSIC), S. Barros, E. Simpson (QUB), report on behalf of a 
larger collaboration:

We observed the afterglow of GRB 090102 (Mangano et al., GCN 8762; Klotz 
et al., GCN 8761) with the Nordic Optical Telescope equipped with 
ALFOSC, at several epochs. The decay in the R band is consistent with a 
single power law with slope alpha ~ 0.9 between 0.1 and 3 days after the 
GRB. This is in agreement with the early-time slopes reported by Afonso 
et al. (GCN 8771) and Cenko et al. (GCN 8773). There is marginal 
indication that the light curve may flatten at late times, which could 
be due to the presence of a host galaxy. Further observations are 
encouraged.

A plot with the light curve, including data from GROND (GCN 8771), P60 
(GCN 8773), and IAC80 (de Ugarte Postigo et al., GCN 8772) is posted at 
the following URL:

http://www.astro.ku.dk/~malesani/GRB/090102/lc.png

[GCN OPS NOTE(05jan09): Per author's request, the Klotz reference
was changed from 8762 to 8761.]


GRB_name: GRB081231A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8781
SUBJECT: GRB 081231: Fermi GBM Detection
DATE:    09/01/06 02:43:13 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (UAH) and R. Preece (UAH) 
report on behalf of the Fermi GBM Team: 

"At 03:21:01.93 UT on 31 December 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081231 (trigger 252386462 / 081231140).

The on-ground calculated location, using the GBM trigger 
data, is RA = 218.74, DEC = -38.72 (J2000 degrees, 
equivalent to 14 h 35 m, -38 d 43'), with an uncertainty 
of 1.0 degree (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 20 degrees.
This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of three main emission peaks with
apparent substructure and a duration (T90) of about 29 s (8-1000 keV). 
The time-averaged spectrum from T0-4.1 s to T0+37.9 s is best fit by
a Band function with Epeak = 152.3 +/- 11.9 keV, 
alpha = -0.80 +/- 0.06, and beta = -2.03 +/- 0.07. 
(chi squared 998 for 726 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
1.2E-05 +/- 5.9E-07 erg/cm^2. The peak photon flux measured 
starting from T0-4.1 s in the 8-1000 keV band 
is 1.53 +/- 0.08 ph/s/cm^2. 

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090107A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8782
SUBJECT: GRB 090107: Swift detection of a burst
DATE:    09/01/07 05:00:06 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

T. N. Ukwatta (GSFC/GWU), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
W.B Landsman (GSFC), D. M. Palmer (LANL), M. Perri (ASDC) and
G. Stratta (ASDC) report on behalf of the Swift Team:

At 04:48:04 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090107 (trigger=339295).  Swift could not slew
to this burst due to its proximity to the Sun. 
The BAT on-board calculated location is 
RA, Dec 302.426, +4.727 which is 
   RA(J2000) = 20h 09m 42s
   Dec(J2000) = +04d 43' 39"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 25 sec, with a possible additional
peak at T+75 sec.  The peak count rate was ~2000 counts/sec (15-350 keV),
at ~0 sec after the trigger. 

Due to the Sun observing constraint, Swift cannot slew to the 
BAT position.  There will thus be no XRT or UVOT data for this trigger. 

Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090107A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8783
SUBJECT: GRB 090107: Swift-BAT refined analysis
DATE:    09/01/07 13:51:47 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

G. Sato (ISAS), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090107 (trigger #339295)
(Ukwatta, et al., GCN Circ. 8782).  The BAT ground-calculated position is
RA, Dec = 302.409, 4.744 deg, which is 
   RA(J2000)  =  20h 09m 38.2s 
   Dec(J2000) = +04d 44' 37.9" 
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 74%.
 
The mask-weighted light curve shows two peaks.  The first is about 1.2 sec wide
and peaks at ~T+0.9 sec.  The second is about 6 sec wide and peaks at ~T+11 sec.
Because of the Sun observing constraint and because of a regular pre-planned 
target slew, the BAT has no data on this event past T+260 sec, until the next orbit.
T90 (15-350 keV) is 12.2 +- 0.7 sec (estimated error including systematics).
 
The time-averaged spectrum from T+0.2 to T+12.9 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.69 +- 0.27.  The fluence in the 15-150 keV band is 2.3 +- 0.5 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.30 sec in the 15-150 keV band
is 1.1 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/339295/BA/


GRB_name: GRB081225A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8784
SUBJECT: Fermi/GBM detection of GRB 081225
DATE:    09/01/07 16:46:18 GMT
FROM:    Chryssa Kouveliotou at MSFC  <chryssa.kouveliotou@nasa.gov>

Chryssa Kouveliotou (NASA/MSFC), Valerie Connaughton (UAHuntsville) report on behalf of the Fermi GBM Team: 

"At 06:09:21.34 UT on 25 December 2008, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 081225 (trigger 251878162/081225256).

The on-ground calculated location, using the GBM trigger data, is RA = 234.1, DEC = -64.6 (J2000 degrees, equivalent to 15 h 36.5 m, -64 d 36 '), with an uncertainty of 6.9 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 55 degrees.

The GBM light curve consists of a single pulse with a duration (T90) of about 42 s (50-300 keV).  The time-averaged spectrum from T0-18.43 s to T0+18.43 s is best fit by a simple power law function with index -1.51+/- 0.04 (chi squared 233 for 220 d.o.f.).

The event fluence (50-300 keV) in this time interval is (2.45 +/- 0.06)E-6 erg/cm^2. The 6.14-sec peak photon flux measured starting from T0-6.144 s in the 50-300 keV band is 0.60 +/- 0.02 ph/s/cm^2.

The spectral and timing analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."


GRB_name: GRB081226A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8785
SUBJECT: Fermi/GBM detection of GRB 081226A
DATE:    09/01/07 16:48:20 GMT
FROM:    Chryssa Kouveliotou at MSFC  <chryssa.kouveliotou@nasa.gov>

Chryssa Kouveliotou (NASA/MSFC), Valerie Connaughton (UAHuntsville) report on behalf of the Fermi GBM Team: 

"At 01:03:37.53 UT on 26 December 2008, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 081226 (trigger 251946218, trigcat 081226044), which was also detected by the SWIFT-BAT (Godet et al. 2008, GCN 8729). The on-ground calculated location, using the GBM trigger data, is RA = 119.01, DEC = -73.8 (J2000 degrees, equivalent to 07 h 56.04 m, -73 d 48'), with an uncertainty of 13.2 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The GBM on-ground location is consistent with the Swift position.
 
The angle from the Fermi LAT boresight is 110 degrees.

The GBM light curve is a single pulse with a duration (T90) of about 1.7 s (20-775 keV). The time-averaged spectrum from T0-0.215 s to T0+0.233 s is best fit by a simple power law function with index 1.17 +/- 0.08 (chi squared 188 for 228 d.o.f.).

The event fluence (50-300 keV) in this time interval is (2.1 +/- 0.1)E-7 erg/cm^2. The 0.256-sec peak photon flux measured starting from T0-0.151 s in the 50-300 keV band is 3.2 +/- 0.1 ph/s/cm^2.

The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."


GRB_name: GRB090107B
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8786
SUBJECT: GRB 090107B: a long GRB localized by INTEGRAL
DATE:    09/01/07 17:05:19 GMT
FROM:    Diego Gotz at CEA  <diego.gotz@cea.fr>

D. Gotz (CEA-Saclay), S.Mereghetti, A.Paizis (IASF-Milano), C. Ferrigno,
V.Beckmann, M. Beck (ISDC, Versoix), and J. Borkowski (CAMK, Torun) on
behalf of the IBAS Localization Team report:

A GRB lasting about 20 s has been detected by IBAS in IBIS/ISGRI data at
16:20:36 UT on January 7th. The refined coordinates (J2000)  are:

RA = 284.8075 [degrees]
DEC= 59.5924 [degrees]

with an uncertainty of 1.5 arcmin (90% c.l.).

A preliminary analysis gives a peak flux in the 20-200 keV range of
about 1.6 ph/cmsq/s (1-s integration time) and a fluence over the  
same energy
range of about 1.5e-6 erg/cmsq. Both values have to be considered  
lower limits,
since the burst is affected by telemetry saturation.

A plot of the light curve will be posted at

http://ibas.iasf-milano.inaf.it/IBAS_Results.html

This message can be cited.


GRB_name: GRB090107B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8787
SUBJECT: GRB 090107B: ROTSE-III Optical Limits  
DATE:    09/01/07 17:48:17 GMT
FROM:    Tolga Guver at UA  <tolga@physics.arizona.edu>

GRB 090107B: ROTSE-III Optical Limits

T. Guver (U Arizona), H. Swan (U Mich), report on behalf of the ROTSE  
collaboration:
ROTSE-IIId, located at the TUBITAK National Observatory at  
Bakirlitepe, Turkey, responded to GRB 090107B (INTEGRAL trigger 5398;  
D. Gotz, GCN 8786), producing images beginning 0.0 s after the GCN  
notice time. An automated response took the first image at 16:20:40.7  
UT, 4.7 s after the burst, and during the gamma-ray emission, under  
fair conditions. We took 10 5-sec, 10 20-sec and 63 60-sec exposures.  
These unfiltered images are calibrated relative to USNO A2.0 (R).  
Imaging is on going.

Comparison to the DSS (second epoch) reveals no new sources within the  
3-sigma INTEGRAL/IBIS error circle, for both single images and  
coadding into sets of 10. Individual images have limiting magnitudes  
ranging from 16.2-16.6; we set the following specific limits.

start UT end UT  t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
16:26:35.8 16:26:55.8 20 16.6 359.8 N
16:28:03.0 16:32:41.6 278 17.7 447.0 Y


GRB_name: GRB090107B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8788
SUBJECT: GRB 090107B optical observations
DATE:    09/01/07 17:53:05 GMT
FROM:    Arne A. Henden at AAVSO  <arne@aavso.org>

Arto Oksanen (Hankasalmi Obs., Hankasalmi, Finland) reports via the
AAVSO High Energy Network the following optical observations of the
INTEGRAL burst GRB 090107B (Gotz et al., GCN Circular #8786):

Unfiltered observations were made using a 0.4-meter RC telescope
with an SBIG STL-1001E CCD.  The full INTEGRAL error box was
observed unfiltered starting at 16:35UT, 15 minutes after the
burst.  Combining ten 60-second exposures, we do not see any
optical afterglow to a limiting magnitude of 20.5 (compared
with the DSS2 red plate).

A FITS image of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/ArtoOksanen_GRB090107_2454839.23238_.fits

The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.


GRB_name: GRB090107B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8789
SUBJECT: GRB 090107B: Swift-XRT detection of possible afterglow
DATE:    09/01/07 21:09:39 GMT
FROM:    Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>

M. Perri (ASDC) and P. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

Swift began observing the field of the INTEGRAL GRB 090107B (Gotz et
al., GCN Circ. 8786) 4.2 ks after the trigger. A single uncatalogued
source was identified within the IBIS/ISGRI error circle.

Using 1314 s of XRT Photon Counting mode data and 2 UVOT images, we find
an astrometrically corrected X-ray position (using the XRT-UVOT alignment
and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec =
284.81750, 59.59510 which is equivalent to:

RA (J2000):  18 59 16.21
Dec (J2000): +59 35 42.3

with an uncertainty of 1.8 arcsec (radius, 90% confidence). The source
lies 21 arcsec from the IBIS/ISGRI centroid and has a count rate of
~0.25 counts/s during this observation.

Currently we cannot determine if this source is fading, and therefore
cannot confirm if this source is associated with GRB 090107B.
Observations of this source are on-going.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090107B
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8790
SUBJECT: GRB 090107B: Swift/UVOT Observations
DATE:    09/01/07 21:41:56 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F.E. Marshall (NASA/GSFC)
reports on behalf of the Swift/UVOT team:

The Swift/UVOT observed the field of GRB 090107B starting 4396 s after
the INTEGRAL trigger (Gotz et al., GCN Circ. 8786). No optical afterglow
is detected in the initial UVOT exposures at the position
of the candidate X-ray afterglow (Perri et al., GCN Circ. 8789).
There is also no obvious optical afterglow candidate
elsewhere in the INTEGRAL error circle.

The 3-sigma upper limits in the UVOT photometric system 
(Poole et al. 2008, MNRAS, 383, 627) for detecting
a source at the position of the XRT candidate are:

Filter          T_start(s)   T_stop(s)      Exp(s)       Mag 

white             5420         5535          113        >20.9
v                 4396         4595          197        >19.6
b                 5216         5415          197        >20.3
u                 5010         5209          197        >20.1
uvw1              4806         5005          197        >20.3
uvm2              4600         4799          197        >20.3
uvw2              4191         4390          197        >20.6

The values quoted above are not corrected for the Galactic extinction due
to the reddening of E(B-V) = 0.046 in the direction of the burst 
(Schlegel et al. 1998).


GRB_name: GRB090107B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8791
SUBJECT: GRB 090107B: Swift XRT afterglow confirmation
DATE:    09/01/09 16:08:56 GMT
FROM:    Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>

G. Stratta (ASDC), M. Perri (ASDC) and J. R. Cummings (GSFC/UMBC)
report on behalf of the Swift-XRT team:

The Swift ToO observations of GRB 090107B started on 2009 Jan 7th
at 17:30:50 UT. XRT data set consists of 5.7 ks exposure in PC mode.
The single, uncatalogued X-ray source observed in the field
of INTEGRAL, previously reported by Perri et al. (GCN Circ. 8789),
shows fading flux, confirming its afterglow nature.

The 0.3-10 keV light curve from T + 4.2 ks to T + 96.4 ks
possibly indicates evidence for a plateau phase
followed by a steeper decay, but the available data prevented
us from constraining the parameters (i.e. the temporal break and
the two decay indexes). Assuming a simple power law model,
the best fit decay index is alpha = 1.3 +/- 0.1.

The average spectrum accumulated in the same time interval
was fitted with an absorbed power law. The best fit photon
index is 1.8 +/- 0.4. The spectrum shows evidence of absorption
at the level of (9 +/- 1)e20 cm-2, in excess of the
estimated Galactic value (5e20 cm-2, Kalberla et al. 2005).
The average observed[unabsorbed] 0.3-10 keV average flux is
about  2.8[3.6]e-12 ergs cm-2 s-1.

The predicted count rate 48 hours after the trigger is 0.002 cts/s
The count-rate-to-flux conversion factor is 5.2e-11 ergs cm-2 cts-1

All quoted errors are at 90% confidence level.

Burst Advocate for this burst is J. R. Cummings.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8792
SUBJECT: GRB 090102: WSRT Radio Observations
DATE:    09/01/09 16:39:06 GMT
FROM:    Alexander van der Horst at NASA/MSFC  <Alexander.J.VanDerHorst@nasa.gov>

A.J. van der Horst (NASA/MSFC/ORAU), R.A.M.J. Wijers and A.P. Kamble
(University of Amsterdam) report on behalf of a larger collaboration:

"We observed the position of the GRB 090102 afterglow at 4.9 GHz with the
Westerbork Synthesis Radio Telescope at January 8 18.88 UT to January 9
6.86 UT, i.e. 6.66 - 7.16 days after the burst (GCN 8762).
We do not detect a radio source at the position of the optical counterpart
(GCN 8766). The three-sigma rms noise in the map around that position is
72 microJy per beam. The formal flux measurement for a point source at the
position of the optical counterpart is 12 +/- 24 microJy.

We would like to thank the WSRT staff for scheduling and obtaining these
observations."


GRB_name: GRB090107B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8793
SUBJECT: GRB090107B: Fermi GBM Detection
DATE:    09/01/09 23:33:40 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (UAH), R. Preece (UAH), and A.J. van der Horst (NASA/ORAU) 
report on behalf of the Fermi GBM Team: 

"At 16:20:42.77 UT on 07 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090107B (trigger 25303844 / 090107681).

This burst was also detected by the INTEGRAL IBAS
(D. Gotz et al. 2009, GCN 8786)
The GBM on-ground location is consistent with the INTEGRAL position.

The GBM light curve consists of two main emission peaks and apparent
substructure with a duration (T90) of about 24.1 s (8-1000 keV). 
The time-averaged spectrum from T0-4.1 s to T0+20.5 s is 
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.68 +/- 0.26 and
the cutoff energy, parameterized as Epeak, is 106.1 +/- 14.8 keV
(chi squared 530.4 for 486 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(1.75 +/- 0.37)E-06 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+6.1 s in the 8-1000 keV band 
is 3.68 +/- 0.27 ph/s/cm^2.

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090107B
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8794
SUBJECT: GRB 090107B: Suzaku WAM observation of the prompt emission
DATE:    09/01/10 14:30:59 GMT
FROM:    Yujin E. Nakagawa at RIKEN  <yujin@crab.riken.jp>

Y. E. Nakagawa, T. Tamagawa (RIKEN), H. Hayashi, E. Sonoda, M. Yamauchi,
H. Tanaka, R. Hara, N. Ohmori, K. Kono (Univ. of Miyazaki), A. Endo,
M. Tashiro, Y. Terada, Y. Urata, K. Onda, N. Kodaka, K. Morigami,
T. Sugasahara, W. Iwakiri (Saitama U.), T. Enoto, K. Nakazawa,
K. Makishima (Univ. of Tokyo), S. Sugita, K. Yamaoka (Aoyama Gakuin U.),
M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), Y. Hanabata,
T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira (Hiroshima U.),
S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:

The long GRB 090107B (Gotz et al., GCN 8786) was detected by the
Suzaku Wide-band  All-sky Monitor (WAM) which covers an energy range
of 50 keV - 5 MeV at 2009-01-07 16:20:35 UT (=T0).

The observed light curve shows a double-peaked structure lasting from
T0-1 s to T0+20 s with a duration (T90) of about 14 seconds. The fluence
in 100 - 1000 keV was 1.3 (+0.7, -0.9) * 10^-6 erg/cm^2. The 1-s peak
flux measured from T0+13 s was 0.4 +/- 0.3 photons/cm^2/s in the same 
energy range.

Preliminary result shows that the time-averaged spectrum from T0-1 s
to T0+20 s is well fitted by a single power-law with a photon index 
of 2.0 +/- 0.4 (chi^2/d.o.f = 6/10).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves with 1-sec time resolution for this burst will be appeared at:

 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html


GRB_name: GRB090111A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8795
SUBJECT: GRB 090111: Swift detection of a burst
DATE:    09/01/12 00:15:21 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

T. Sakamoto (NASA/UMBC), M. M. Chester (PSU), E. A. Hoversten (PSU),
H. A. Krimm (CRESST/GSFC/USRA), J. Mao (INAF-OAB),
R. Margutti (Univ Bicocca&OAB), F. E. Marshall (NASA/GSFC),
D. M. Palmer (LANL), M. Stamatikos (NASA/ORAU),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 23:58:21 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090111 (trigger=339696).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 251.645, +0.091 which is 
   RA(J2000) = 16h 46m 35s
   Dec(J2000) = +00d 05' 28"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 30 sec.  The peak count rate
was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 23:59:38.3 UT, 76.6 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
variable, uncatalogued X-ray source with an enhanced position: RA, Dec
251.6759, 0.0769 which is equivalent to:
   RA(J2000)  = 16h 46m 42.21s
   Dec(J2000) = +00d 04' 36.8"
with an uncertainty of 3.0 arcseconds (radius, 90% containment). This
location is 122 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
6.45e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 3.05e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 86 seconds after the BAT trigger. No credible
afterglow candidate has  been found in the initial data products. The
2.7'x2.7' sub-image covers 100% of  the XRT error circle. The 3-sigma
upper limit at the location of the XRT candidate is 19.3 mag.  The
8'x8' region for the list of sources generated on-board covers 100%
of the  XRT error circle. The list of sources is typically complete
to about 18 mag. No  correction has been made for the expected
extinction corresponding to E(B-V) of  0.16. 

Burst Advocate for this burst is T. Sakamoto (Taka.Sakamoto AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090111A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8796
SUBJECT: GRB 090111: Enhanced Swift-XRT position
DATE:    09/01/12 04:41:17 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1667 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 090111, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 251.67557, +0.07728 which is equivalent
to:

RA (J2000): 16h 46m 42.14s
Dec (J2000): +00d 04' 38.2"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB090111A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8797
SUBJECT: GRB 090111: Swift-XRT refined analysis
DATE:    09/01/12 12:05:47 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti (Univ. Bicocca & INAF-OAB), J. Mao (INAF-OAB),
T. Sakamoto (NASA/UMBC) report on behalf of the Swift XRT team:

We have analysed the first 2 orbits of Swift-XRT data obtained for
GRB 090111 (Sakamoto et al., GCN Circ. 8795), covering 70 s of
Windowed Timing (WT) and 4 ks of Photon Counting (PC) mode data,
respectively, between  77 s and 8 ks after the trigger.
The UVOT-enhanced XRT position was given by Evans et al. in
GCN Circ. 8796.

In the time interval 77-150 s, the light curve can be modelled by a
simple power law with a decay index alpha_1= 5.1 +/- 0.3 (90% confidence)
followed by a rebrightening around 0.5 ks.
After the rebrightnening the light curve decays with a powerlaw index
alpha_2= 3.6 +/- 0.4 and then flattens to alpha_3= 0.4 +/- 0.1
with a t_break of 1200 s.

The spectrum extracted from WT data can be modelled with an
absorbed simple power-law, with Gamma = 5.4 +/- 0.5  and
NH = (5.4 +/- 0.8)x10^21 cm^-2 in excess of the Galactic column in
this direction which is 6.5x10^20 cm^-2 (Kalberla et al. 2005).
The observed (unabsorbed) 0.3 -10 keV
flux over this time interval (77-150 s post-trigger) is
3.8x10^-10 (2.7x10^-8) erg cm^-2 s^-1.

The spectrum extracted from PC data in the time interval 150-8000 s
can be modelled with an absorbed power-law, with Gamma= 3.3 +/- 0.5
and an intrinsic column density of NH = (2.0 +/- 0.8)x10^21 cm^-2.
The observed (unabsorbed) 0.3 -10 keV flux over this time
interval is 3.0x10^-12 (1.2x10^-11) erg cm^-2 s^-1.
Uncertainties are given at 90% confidence.

If the light-curve continues to decay with alpha ~0.4, the count rate 24
hours after the burst is estimated to be 1.3x10^-2 count s^-1, which
corresponds to an observed flux of 4x10^-13 erg cm^-2 s^-1.

The results of the xrt automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00339696.

This is an official product of the Swift-XRT team.


GRB_name: GRB090108A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8798
SUBJECT: GRB 090108: Fermi GBM Detection
DATE:    09/01/12 19:00:42 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (UAH) and R. Preece (UAH) 
report on behalf of the Fermi GBM Team: 

"At 00:29:02.37 UT on 08 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090108 (trigger 253067344 / 090108020).

The on-ground calculated location, using the GBM trigger 
data, is RA = 263.04, DEC = 52.46 (J2000 degrees, 
equivalent to 17h 32m, 52d 28'), with an uncertainty 
of 2.93 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 60 degrees.

The GBM light curve consists of a single bright pulse 
followed by a peak of significantly lesser intensity.
The duration of the burst (T90) is about 0.90 s (8-1000 keV). 
The time-averaged spectrum from T0-0.17 s to T0+0.73 s is 
best fit by a Band function with Epeak = 104.8 +/- 16.4 keV, 
alpha = -0.47 +/- 0.20, and beta = -1.97 +/- 0.09 
(chi squared 722.8.5 for 733 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(1.28 +/- 0.24)E-06 erg/cm^2. The 0.064-sec peak photon flux measured 
starting from T0+0.027 s in the 8-1000 keV band 
is 39.7 +/- 3.9 ph/s/cm^2.

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090111A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8799
SUBJECT: GRB 090111: Swift UVOT Upper Limits
DATE:    09/01/12 19:11:09 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) and T. Sakamoto (NASA/UMBC) report on behalf of
the Swift UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 090111 86s after the BAT trigger (Godet et al., GCN 8795).
We do not detect any source at the enhanced Swift XRT position (Evans
et al. GCN 8796).  UVOT magnitude 3-sigma upper limits are reported in
the following table:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
WHITE       86       235     146       > 20.25
WHITE       86      1545     391       > 20.78
v          627      1768     136       > 18.47
b          553      1866     136       > 19.37
u          298       547     245       > 19.56
u          298      1841     608       > 20.03
uvw1       676      1817     136       > 19.22
uvw2       603      1743     136       > 19.52

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.16 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).


GRB_name: GRB090111A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8800
SUBJECT: GRB 090111, Swift-BAT refined analysis
DATE:    09/01/12 20:52:55 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner 
(GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry 
downlink,
we report further analysis of BAT GRB 090111 (trigger #339696)
(Sakamoto et al., GCN Circ. 8795).  The BAT ground-calculated position is
RA, Dec = 251.656, 0.067 deg which is
   RA(J2000)  =  16h 46m 37.4s
   Dec(J2000) = +00d 04' 01.5"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 82%.

The mask-weighted light curve shows two peaks of roughly equal intensity.
The first lasts from T-3 sec to T+9 sec and the second from T+10 to T+26 
seconds.
T90 (15-350 keV) is 24.8 +- 2.7 sec (estimated error including 
systematics).

The time-averaged spectrum from T-2.9 to T+25.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.37 +- 0.17.  The fluence in the 15-150 keV band is 6.2 +- 0.6 x 10-7 
erg/cm2.
The 1-sec peak photon flux measured from T+10.70 sec in the 15-150 keV band
is 0.9 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/339696/BA/


GRB_name: GRB090108B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8801
SUBJECT: GRB 090108B: Fermi GBM detection
DATE:    09/01/12 22:28:05 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi (MPE) and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team:


"At 07:43:23.36 UT on 08 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090108B (trigger 253093405 / 090108322).
The on-ground calculated location, using the GBM trigger
data, is RA = 3.8, DEC = -32.2 (J2000 degrees,
equivalent to 00h 15m, -32d 12'), with an uncertainty
of 6.4 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 72 degrees.

The GBM light curve shows a single spike
with a duration (T90) of about 800 ms (8-1000 keV).
The time-averaged spectrum from T0-0.295 s to T0+0.121 s
is well fit by a simple power law function with
index -0.99 +/- 0.06 (chi squared 246 for 242 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(7.9 +/- 0.4)E-07 erg/cm^2. The 32-ms peak photon flux measured
starting from T0-0.008 s in the 8-1000 keV band
is 19.0 +/- 1.3 ph/s/cm^2.


The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090109A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8802
SUBJECT: GRB 090109: Fermi GBM detection
DATE:    09/01/12 22:30:25 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi(MPE) and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team:


"At 07:58:29.49 UT on Day Month Year, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090109 (trigger 253180711 / 090109332).
The on-ground calculated location, using the GBM trigger
data, is RA = 122.8, DEC = +54.8 (J2000 degrees,
equivalent to 08h 11m, 54d 48'), with an uncertainty
of 12.5 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 62 degrees.

This weak GRB consists of a single peak
with a duration (T90) of about 5 s (8-1000 keV).
The time-averaged spectrum from T0-2.8 s to T0+1.3 s is
well fit by a simple power law function with 
index -1.50 +/- 0.08 (chi squared 236 for 241 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.21 +/- 0.05)E-06 erg/cm^2. The 1.3-sec peak photon flux measured
starting from T0 in the 8-1000 keV band
is 2.76 +/- 0.16 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090112A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8803
SUBJECT: GRB 090112: Fermi GBM detection
DATE:    09/01/13 16:44:12 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi (MPE) and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team: 


"At 07:57:23.11 UT on 12 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090112 (trigger 253439845 / 090112332).
The on-ground calculated location, using the GBM trigger
data, is RA = 111.8, DEC = -30.3 (J2000 degrees,
equivalent to 07h 27m, -30d 17'), with an uncertainty
of 1.7 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 4 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GRB lightcurve consists of two peaks with some substructure
appearing at T0 and T0+4 s, respectively. A possible precursor
is present around T0-20 s and additional weak emission is visible
up to T0+50s. The event duration (T90) is about 65 s (8-1000 keV)
and T50 is about 27 s (8-1000 keV).
The time-averaged spectrum from T0-6 s to T0+18 s is
best fit by a Band function with Epeak =  150 +/- 40 keV,
alpha = -0.94 +/- 0.20 and beta = -2.01 +/- 0.19
(chi squared 464 for 456 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(5.2 +/- 1.0)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T0+4 s in the 8-1000 keV band 
is 7 +/- 2 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090113A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8804
SUBJECT: GRB 090113: Swift detection of a burst
DATE:    09/01/13 19:06:45 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
J. A. Kennea (PSU), C. B. Markwardt (CRESST/GSFC/UMD),
P. T. O'Brien (U Leicester), K. L. Page (U Leicester),
A. M. Parsons (GSFC), B. A. Rowlinson (U Leicester),
T. Sakamoto (NASA/UMBC), E. Troja (INAF-IASFPA),
T. N. Ukwatta (GSFC/GWU), L. Vetere (PSU) and H. Ziaeepour (UCL-MSSL)
report on behalf of the Swift Team:

At 18:40:39 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090113 (trigger=339852).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 32.073, +33.456 which is 
   RA(J2000)  =  02h 08m 18s
   Dec(J2000) = +33d 27' 23"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows about 4 peaks
with a duration of about 20 sec.  The peak count rate
was ~5000 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 18:41:50.1 UT, 70.9 seconds after
the BAT trigger. The onboard source-detection algorithm originally
centroided on a hot column. No other source was visible in the initial
TDRSS sub-image. We are waiting for the full Malindi dataset to detect
and localise the afterglow. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 79 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The sub-image covers 25% of the BAT
error circle.  The overlap of the 8'x8' region for the list of
sources generated on-board is 100% of the BAT error circle.  This source
list is usually complete to about 18th magnitude.  No correction
has been made for the expected extinction corresponding to E(B-V) of 0.08. 

This burst was also detected by Fermi-GBM. 

This burst is not to be confused with the BAT trigger (339853)
about 12 minutes later on the 1A 1118-61 HMXB source. 

Burst Advocate for this burst is H. A. Krimm (krimm AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090112B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8805
SUBJECT: GRB 090112B: Fermi GBM Detection
DATE:    09/01/13 22:21:26 GMT
FROM:    Alexander van der Horst at NASA/MSFC  <Alexander.J.VanDerHorst@nasa.gov>

A.J. van der Horst (NASA/MSFC/ORAU) reports on behalf of the
Fermi GBM Team:

"At 17:30:15.45 UT on 12 January 2009, the Fermi Gamma-ray Burst Monitor
(GBM) triggered and located GRB 090112B (trigger 253474217 / 090112.729).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 192.7, Dec = +22.2 (J2000 degrees, equivalent to
J2000 12h51m, +22d12'), with a statistical uncertainty of 2.1 degrees
(radius, 1-sigma containment, statistical only; there is additionally
a systematic error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 95 degrees.

The GBM light curve shows one pulse with some substructure, with a
duration (T90) of about 12 s (50-300 keV). The time-averaged spectrum
from T0 to T0+8.70 s is best fit by a Band function with
Epeak = 139 +/- 9 keV, alpha = -0.75 +/- 0.06 and beta = -2.43 +/- 0.14.
The fluence (8-1000 keV) in this time interval is (5.4 +/- 0.3)E-6 
erg/cm^2.
The 1-sec peak photon flux measured starting from T0+2.6s in the 8-1000 keV
band is 14 +/- 1 ph/s/cm^2.

The spectral and temporal analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090113A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8806
SUBJECT: GRB090113: XRT position
DATE:    09/01/13 22:35:51 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>

J. A. Kennea (PSU) and H. A. Krimm (CRESST/GSFC/USRA) report on behalf of 
the Swift Team:

Analysis of preliminary data from the BAT trigger 339852 (GRB090113) 
reveals an uncatalogued point source at RA, Dec = 32.05816, 33.42945 which 
is equivalent to:

RA(J2000) = 02h 08m 13.9s,
Dec(J2000) = +33d 25m 46.0s

with an estimated uncertainty of 8 arcseconds radius (90% confidence). 
Analysis is ongoing and an improved analysis will be reported as soon as 
possible.

[GCN OPS NOTE(14jan09): Per author's request, the 090213 was changed
to 090113.]


GRB_name: GRB090113A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8807
SUBJECT: GRB 090113: ROTSE-III Optical Limits
DATE:    09/01/13 23:23:49 GMT
FROM:    Heather Swan at U.of Michigan/ROTSE  <hflewell@umich.edu>

H. Swan (U Mich), E.S. Rykoff (UCSB), T. Guver (U Arizona), T.A. McKay 
(U Mich), F. Yuan (U Mich), B. E. Schaefer (Louisiana State), R. Quimby 
(Caltech), report on behalf of the ROTSE collaboration:

ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe, 
Turkey, responded to GRB 090113 (Swift trigger 339852; H. A. Krimm, GCN 
8804), producing images beginning 6.4 s after the GCN notice time. An 
automated response took the first image at 18:49:02.4 UT, 503.2 s after 
the burst, under windy conditions. We took 10 5-sec, 10 20-sec and 30 
60-sec exposures. These unfiltered images are calibrated relative to 
USNO A2.0 (R). Imaging is on going.

Comparison to the DSS (second epoch) reveals no new sources within the 
3-sigma Swift/BAT error circle, for both single images and coadding into 
sets of 10; the field is not crowded. Individual images have limiting 
magnitudes ranging from 14.9-16.4; we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
18:49:02.5   18:51:08.2       125     16.6          503.3       Y
18:51:16.6   18:55:52.3       275     17.3          637.4       Y
18:60:45.7   19:05:21.5       275     17.3         1206.5       Y


GRB_name: GRB090113A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8808
SUBJECT: GRB 090113: Swift-BAT refined analysis
DATE:    09/01/14 00:07:29 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

GRB 090113: Swift-BAT refined analysis
 
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-120 to T+302 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090113 (trigger #339852)
(Krimm, et al., GCN Circ. 8804).  The BAT ground-calculated position is
RA, Dec = 32.067, 33.436 deg, which is 
   RA(J2000)  =  02h 08m 16.0s 
   Dec(J2000) = +33d 26' 08.4" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 80%.
 
The mask-weighted light curve shows multiple peaks starting at ~T-10 sec
and ending at ~T+30 sec.  T90 (15-350 keV) is 9.1 +- 0.9 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-0.9 to T+10.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.60 +- 0.10.  The fluence in the 15-150 keV band is 7.6 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+1.46 sec in the 15-150 keV band
is 2.5 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/339852/BA/


GRB_name: GRB090113A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8809
SUBJECT: GRB 090113: Enhanced Swift-XRT position
DATE:    09/01/14 00:31:07 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 752 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 090113, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 32.05678, +33.42857 which is equivalent
to:

RA (J2000): 02h 08m 13.63s
Dec (J2000): +33d 25' 42.9"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB090113A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8810
SUBJECT: GRB 090113: Observations from NOT
DATE:    09/01/14 05:59:12 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (ESO), J. Gorosabel (IAA-CSIC),
D. Malesani (DARK/NBI), J.H. Knapen, J.R. Snchez Gallego (IAC),
P. Stiles (Obs. del Sauzal) on behalf of a larger collaboration report

We have observed the field of GRB 090113 (Krimm et al.,
GCN 8804) with the 2.5m NOT telescope at Roque de los
Muchachos Observatory (La Palma, Spain). Preliminary
analysis of a 300s R-band exposure with mid time 20:45
UT (2.08h after the burst) does not show any new source
within the enhanced XRT error box (Goad et al., GCN
8809) down to a 3-sigma limiting magnitude of  R > 23.4.

[GCN OPS NOTE(14jan09): Per author's request, DM was added
to the author list.]


GRB_name: GRB090113A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8811
SUBJECT: GRB 090113: Swift-XRT refined analysis
DATE:    09/01/14 07:37:44 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans (U. Leicester)  and H. A. Krimm (CRESST/GSFC/USRA) report on behalf
of the Swift-XRT team:

We have analysed 5.5 ks of XRT data for GRB 090113 (Krimm et al. GCN Circ.
8804), beginning 93 s after the BAT trigger. The data are entirely in Photon
Counting (PC) mode. The enhanced XRT position for this burst was given by Goad
et al. (GCN. Circ 8809).

The light curve can be modelled with a power-law decay with a decay index of
alpha=0.991 (+/-0.042).

A spectrum formed from the PC mode data can be fitted with an absorbed power-law
with a photon spectral index of 2.28 (+0.20, -0.19). The best-fitting absorption
column is 3.20 (+0.63, -0.58) x 10^21, in excess of the Galactic value of 6.7 x
10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10
keV flux conversion factor deduced from this spectrum is 4.0 x 10^-11 (7.8 x
10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 0.991, the
count rate at T+24 hours will be 0.0063 count s^-1, corresponding to an observed
(unabsorbed) 0.3-10 keV flux of 2.5 x 10^-13 (4.9 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00339852.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090113A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8812
SUBJECT: GRB 090113: GROND Upper Limits
DATE:    09/01/14 08:36:44 GMT
FROM:    Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>

F. Olivares (MPE Garching), Andrea Rossi (Tautenburg Obs.), J. Greiner,
A. Yoldas (both MPE Garching), and A. Kupcu Yoldas (ESO) report on behalf
of the GROND team:

We observed the field of GRB 090113 (Swift trigger #339852; Krimm et al.,
GCN #8804) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2m MPI/ESO telescope at La Silla
Observatory (Chile).

Observations started at 00:35 UT on January 14th, 2009, about 6.1 hrs after
the GRB trigger, and continued until the GRB location approached the 20 degree
above horizon limit of the telescope, with 8.1 min of total exposures in
g'r'i'z' and 12.0 min in JHK. They were performed at an average seeing of 1.8"
and at an average airmass of 2.6.

We do not detect any object within the 1.7'' Enhanced Swift-XRT error circle
reported by Goad et al. (GCN #8809). Co-added images yield the following
upper limits (all in AB system):

g' >  23.3 mag,
r' >  23.4 mag,
i' >  22.6 mag,
z' >  22.6 mag,
J  >  21.3 mag,
H  >  20.7 mag and
K  >  20.0 mag.

These upper limits are derived based on calibrating the images against the
GROND zeropoints as well as 2MASS field stars. 


GRB_name: GRB090113A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8813
SUBJECT: GRB 090113: Swift UVOT upper limits
DATE:    09/01/14 13:39:14 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (MSSL-UCL) and H.A. Krimm (CRESST/GSFC/USRA) report on  
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 090113 79s after the BAT trigger (Krimm et al., GCN 8804).
We do not detect any source at the enhanced Swift XRT position
(Evans et al. GCN 8809). Due to trigger 339853 the automatic
target sequence was cut short and only the white and u finding charts  
were taken.
In the u finding chart and in the second orbit of data the XRT position
lies outside of the UVOT images. Therefore, we can only report the 3- 
sigma upper
limit for the white finding chart exposure.

The 3-sigma upper limits for the finding chart exposure is:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white      79       229      147     > 20.73
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.08 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).


GRB_name: GRB090113A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8814
SUBJECT: GRB 090113: LOAO Detection Limits in R, I, z, Y-band
DATE:    09/01/15 06:53:10 GMT
FROM:    Induk Lee at Seoul National U  <idlee@astro.snu.ac.kr>

Induk Lee, M. Im (Seoul National University, Korea), Y. Urata (ASIAA,
Taiwan; Saitama University, Japan), and T.S. Yoon (Kyungpook National
University, Korea)

We have observed the field of GRB 090113 (Krimm et al. GCN 8804) with 1.0m
telescope at Mt. Lemmon Optical Astronomy Observatory (LOAO) in Arizona. We
took R, I, z, Y-band images beginning at UT 02:00:28 and UT 02:29:47 on
January 14 2009 respectively. On stacked images with 3 x 300 secs exposures
in R and I-band images, no new source was detected.
The starting points of observation and 3 sigma detection limits (5" aperture
mag) are as below.

-------------------------------------------------------------------------------------------------------
Band        Starting point                     exp.             detection
limit
-------------------------------------------------------------------------------------------------------
R             07h 19m 49s after trigger     3x300sec        21.1
I             07h 49m 08s after trigger     3x300sec        20.5
-------------------------------------------------------------------------------------------------------

The detection limit was calibrated by USNO B1.0 stars.
This message may be cited.

-- 
Induk Lee
http://astro.snu.ac.kr/~idlee
PhD. candidate in Astronomy program,
Department of Physics & Astronomy, FPRD,
Seoul National University,
Seoul, 151-747, Korea


GRB_name: GRB090112B
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8815
SUBJECT: GRB 090112B: Suzaku WAM observation of the prompt emission
DATE:    09/01/16 10:21:36 GMT
FROM:    Kazutaka Yamaoka at Aoyama Gakuin U  <yamaoka@phys.aoyama.ac.jp>

M. Suzuki, M. Ohno, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. E. Nakagawa, T. Tamagawa (RIKEN), H. Hayashi, E. Sonoda, M. Yamauchi,
H. Tanaka, R. Hara, N. Ohmori, K. Kono (Univ. of Miyazaki), A. Endo,
M. Tashiro, Y. Terada, Y. Urata, K. Onda, N. Kodaka, K. Morigami,
T. Sugasahara, W. Iwakiri (Saitama U.), T. Enoto, K. Nakazawa,
K. Makishima (Univ. of Tokyo), S. Sugita, K. Yamaoka (Aoyama Gakuin U.),
Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa,
C. Kira (Hiroshima U.), S. Hong (Nihon U.), on behalf of
the Suzaku WAM team, report:

The long GRB 090112B (van der Horst et al., GCN 8805) triggered the
Suzaku Wide-band All-sky Monitor (WAM) which covers an energy
range of 50 keV - 5 MeV at 2009-01-12 17:30:14 UT (=T0).

The observed light curve shows multiple peaks and lasting from
T0-1 s to T0+12 s with a duration (T90) of about 8 seconds. The fluence
in 100 - 1000 keV was (5.2 +/- 0.3) x 10^-6 erg/cm^2. The 1-s peak
flux measured from T0+3 s was 3.5 (+0.2/-0.3) photons/cm^2/s in the
same energy range.

Preliminary result shows that the time-averaged spectrum from T0-1 s
to T0+12 s is well fitted by a single power-law with a photon index
of 2.46 +/- 0.14 (chi^2/d.o.f = 18/22).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB090102A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8816
SUBJECT: GRB090102: MAGIC telescope GeV observation
DATE:    09/01/16 12:16:42 GMT
FROM:    Markus Garczarczyk at MPI/MAGIC  <garcz@mppmu.mpg.de>

Gaug M. (IAC Tenerife), Antonelli L. A. (INAF Rome),
Bastieri D. (Univ. Padova), Becerra J. G. (IAC Tenerife),
Carosi A. (INAF Rome), Covino S. (INAF Rome), Galante N. (MPI Munich), 
Garczarczyk M. (IFAE Barcelona), La Barbera A. (INAF Palermo),
Longo F. (INFN Trieste), Persic M. (Univ. Udine), Scapin V. (Univ. Udine), 
and Teshima M. (MPI Munich) for the MAGIC collaboration

The MAGIC Imaging Atmospheric Cherenkov Telescope performed a follow-up
observation of GRB090102 (Mangano et al., circular 8762). We started data 
taking with MAGIC at 03:14:52 UT under excellent observation conditions. 
The observation continued for 13149 s.

No evidence for VHE gamma-ray emission above a (preliminary) analysis 
threshold of 89 GeV was found.

A preliminary analysis, for the hypothesis of steady emission and 
assumption of a differential photon spectral index of -2.5, yields the 
following 95% CL differential flux upper limits, including a 30% 
systematic uncertainty on the telescope efficiency. (Because of the 
changing telescope sensitivities due to different zenith angle ranges 
during the observation of GRB090102, the data sample was split into
5 parts):

E (  80- 125 GeV): 2.30 * 10^-10 erg/cm^2/s
E ( 125- 175 GeV): 1.61 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV): 0.34 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV): 0.04 * 10^-10 erg/cm^2/s
for a time window from 03:14:01 UT to 04:21:01 UT

E (  80- 125 GeV): 1.12 * 10^-10 erg/cm^2/s
E ( 125- 175 GeV): 0.50 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV): 0.20 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV): 0.07 * 10^-10 erg/cm^2/s
for a time window from 04:21:01 UT to 05:31:00 UT

E ( 125- 175 GeV): 1.02 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV): 0.30 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV): 0.20 * 10^-10 erg/cm^2/s
for a time window from 05:39:00 UT to 06:02:00 UT

E ( 125- 175 GeV): 2.40 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV): 0.49 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV): 0.25 * 10^-10 erg/cm^2/s
for a time window from 06:02:00 UT to 06:25:00 UT

E ( 175- 300 GeV): 0.40 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV): 0.11 * 10^-10 erg/cm^2/s
for a time window from 06:25:00 UT to 07:02:00 UT

We can also exclude emission of a constant flux in any 100s time bin 
smaller than:

E (  80- 125 GeV): 12.58 * 10^-10 erg/cm^2/s
E ( 125- 175 GeV):  7.53 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV):  3.27 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV):  1.41 * 10^-10 erg/cm^2/s
for a time window from 03:14:01 UT to 04:21:01 UT

E (  80- 125 GeV): 18.16 * 10^-10 erg/cm^2/s
E ( 125- 175 GeV): 15.56 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV):  3.46 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV):  1.40 * 10^-10 erg/cm^2/s
for a time window from 04:21:01 UT to 05:31:00 UT

E ( 125- 175 GeV): 11.61 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV):  2.47 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV):  0.91 * 10^-10 erg/cm^2/s
for a time window from 05:39:00 UT to 06:02:00 UT

E ( 125- 175 GeV): 12.38 * 10^-10 erg/cm^2/s
E ( 175- 300 GeV):  5.38 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV):  1.53 * 10^-10 erg/cm^2/s
for a time window from 06:02:00 UT to 06:25:00 UT

E ( 175- 300 GeV): 10.06 * 10^-10 erg/cm^2/s
E ( 300-1000 GeV):  1.28 * 10^-10 erg/cm^2/s
for a time window from 06:25:00 UT to 07:02:00 UT

Further analysis, exploiting the recently upgraded event trigger, is still 
underway for energies below 80 GeV.

This message can be cited.


GRB_name: GRB090117A
Detection_method: superAGILE
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8817
SUBJECT: GRB 090117 - SuperAGILE Localization of a long GRB
DATE:    09/01/17 17:35:37 GMT
FROM:    Marco Feroci at IASF/INAF  <feroci@iasf-roma.inaf.it>

I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto,
L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda
(INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen,
S. Mereghetti, A. Pellizzoni, F. Perotti, P.
Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti,
M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi,
M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V.
Vittorini, A. Argan, A. Trois, G. Piano, S. Sabatini (INAF/IASF Rome), 
G. Barbiellini, F. Longo, E. Moretti (INFN Trieste), P. Picozza, 
A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita' 
dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and  P. Giommi, C. 
Pittori, B. Preger, P. Santolamazza, F. Verrecchia (ASDC) and L. Salotti 
(ASI), on behalf of the AGILE Team, report:

"SuperAGILE detected a gamma ray burst on 17 January 2009, at 15:21:54 UT.
The event had a duration of about 10.0 s in the 20-60 keV energy range,
with a precursor followed by the main peak. Assuming a crab-like energy 
spectrum, the peak flux on 1-s timescale was about 
2.7E-07 erg/cm2/s. 
The burst position was reconstructed  as (RA, Dec)
(164.003 deg, -58.249 deg), which is:

RA(J2000)  = 10h 56m 00.75s
Dec(J2000) = -58d 14' 57.84"

with an uncertainty of 3' radius. The given uncertainty accounts
for both the statistical and systematic errors.

An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."

This message may be cited.


GRB_name: GRB090117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8818
SUBJECT: GRB090117: Swift-XRT detection of a possible candidate afterglow
DATE:    09/01/18 00:04:10 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team :

The Swift-XRT began observing the field of the SuperAGILE GRB 090117 at 
2009-01-17 19:10:13 UT, 13.7 ks after the burst. In a 1.9 ks Photon 
Counting mode X-ray image covering the 0.3-10 keV band, we detect an 
uncatalogued source within the SuperAGILE error circle at the 
astrometrically corrected X-ray position (using the XRT-UVOT alignment and 
matching UVOT field sources to the USNO-B1 catalogue) of RA, Dec = 
164.0444, -58.2336 which is equivalent to:

RA (J2000):  10 56 10.66
Dec (J2000): -58 14 00.8

with an uncertainty of 2.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest 
position can be viewed at http://www.swift.ac.uk/xrt_positions. The
position  enhancement is described by Goad et al. (2007, A&A, 476, 1401 
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is 
an extension of this method.

At this stage we cannot tell if the source is fading to confirm that it
is the X-ray counterpart of the SuperAGILE  burst.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090117A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8819
SUBJECT: GRB090117 Swift/UVOT upper limits
DATE:    09/01/18 03:23:36 GMT
FROM:    Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>

P. Schady (MSSL-UCL) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began observing the field of SuperAGILE GRB 090117  
(Donnarumma et al., GCN 8817) at 2009-01-017 19:10:14 UT, 13.7 ks  
after the burst. We do not detect any source at the Swift XRT position  
(Beardmore et al., GCN 8818), although we note that there is a bright  
star with v-band magnitude v = 17.7 that lies within the XRT error  
circle.

The UVOT 3-sigma upper limits are reported below:

Filter   T_start   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white      14.4       455      > 17.18
v              15.1       595      > 16.18
b              13.8       627      > 17.08
u              13.7       63        > 17.27
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected  
Galactic extinction along the line of sight of E_(B-V) = 1.63 mag. All  
photometry is on the UVOT photometric system described in Poole et al.  
(2008, MNRAS, 383, 627).


GRB_name: GRB090117A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8820
SUBJECT: GRB 090117: GROND Upper Limits
DATE:    09/01/18 04:13:15 GMT
FROM:    Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>

A. Rossi (Tautenburg Obs.), F. Olivares (MPE Garching), A. Kupcu Yoldas (ESO), J. Greiner, and A. Yoldas (both MPE Garching) report on behalf
of the GROND team:

We observed the field of GRB 090117 (SuperAGILE trigger, Donnarumma et al. GCN #8817) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2m MPI/ESO telescope at La Silla (Chile).
Observations started at 01:40 UT, about 9 hrs after the GRB.

We do not detect any new sources within the 5-sigma Swift/XRT error circle  (Breadmore & Evans, GCN #8818). Note that there is a R~16 magnitude star within the XRT position contaminating the search for the GRB afterglow. Co-added images of the first 8 minutes yield the following specific limits (in AB magnitudes):

g' > 23.7
r' > 24.1
i' > 23.2
z' > 22.2
J > 21.9
H > 20.9
K > 20.3

The magnitudes are calibrated against the GROND zeropoints and 2MASS field stars.


GRB_name: GRB090117A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8821
SUBJECT: GRB 090117 - Fermi GBM Observations
DATE:    09/01/18 05:58:26 GMT
FROM:    Valerie Connaughton at MSFC  <valerie@nasa.gov>

Valerie Connaughton (UAH) reports on behalf of the Fermi GBM Team:

"At 15:22:01.05 UT on 17 Jan 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090117 (trigger 253898523 / 090117640)
which was also detected by SuperAGILE (Donnarumma et al. 2009,
GCN 8817).

The GBM on-ground location is consistent with the reported
position from SuperAGILE. The angle from the Fermi LAT boresight is
51 degrees.

The GBM light curve shows a soft event with a single peak lasting
about 2 seconds superimposed on a lower-level continuum.
The burst duration (T90) is about 21 s (8-1000 keV).
The time-averaged spectrum from T0-5 s to T0+4 s is
best fit by a Band function with Epeak = 25 +/- 2 keV,
alpha = -0.4 +/- 0.5, and beta = -2.5 +/- 0.1

The event fluence (8-1000 keV) in this time interval is
(1.8 +/- 1.3)E-6 erg/cm^2, with a 1 sec peak flux starting
at T0 of 9.6 +/- 4.2 ph/cm^2/s and a 0.256 sec peak flux starting
at T0+0.256 sec of 18.6 +/- 8.0 ph/cm^2/s.

In view of the soft spectrum and the position of the burster close to
the Galactic plane, other spectral forms were investigated that are
more typical of galactic transient sources.   Of these, the best fit was
obtained using a thermal Bremmstrahlung model with kT = 49. 
The Band GRB function was preferred statistically with delta chi2
= -5 for 1 extra parameter. It is likely, therefore, that this is a soft
GRB rather than a new galactic transient.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090117C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8822
SUBJECT: GRB 090117C - Fermi GRB Detection
DATE:    09/01/18 06:15:23 GMT
FROM:    Valerie Connaughton at MSFC  <valerie@nasa.gov>

Valerie Connaughton (UAH) reports on behalf of the Fermi GBM Team:

"At 15:10:40.18 UT on 17 Jan 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090117C (trigger 253897842 / 090117632).

The on-ground calculated location, using the GBM trigger
data, is RA = 117.6, DEC = -40.3 (J2000 degrees,
equivalent to 07h 50m, -40d 18'), with an uncertainty
of 1.8 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 54 degrees.

The GBM light curve consists of a precursor lasting tens
of seconds until trigger time, followed by a single episode with
substructure lasting a further 35 s.  The total duration (T90)
between 8 and 1000 keV is about 86 s.
 
The time-averaged spectrum of the main emission
from T0-2 s to T0+29 s is best fit by a Band function with
Epeak = 247 +/- 41 keV, alpha = -1.0 +/- 0.1, and
beta = -2.1 +/- 0.2, giving an 8-1000 keV fluence of
(1.1 +/- 0.1) E-5 erg/cm^2.  

The precursor spectrum from T0-55 sec to T0-6 s is best fit
using a power law function with an exponential
high energy cutoff.  The power law index is -1.3 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 147 +/- 38 keV.
The 8-1000 keV fluence of the precursor is
(3.9 +/- 0.5) E-6 erg/cm^2.

A 1-sec peak photon flux of 4.2 +/- 0.7 ph/s/cm^2
in the 8-1000 keV band is measured starting at T0+22.5 s.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8823
SUBJECT: GRB 090117: confirmation of the X-ray afterglow
DATE:    09/01/18 07:55:36 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page & A.P. Beardmore (U. Leicester) report on behalf of the 
Swift-XRT team:

Following the collection of further XRT data, we see that the source found 
by Beardmore & Evans (GCN Circ. 8818) is fading, so confirm it as the 
X-ray afterglow of GRB 090117 (Donnarumma et al., GCN Circ. 8817; 
Connaughton, GCN Circ. 8821).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090117B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8824
SUBJECT: GRB 090117B : Fermi GBM detection
DATE:    09/01/18 12:31:04 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

Andreas von Kienlin (MPE) reports on behalf of the Fermi GBM Team:

"At 08:02:02.23 UT on 17 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090117B (trigger 253872124  / 090117335)
The on-ground calculated location, using the GBM trigger
data, is RA = 232.9, DEC = 27.6  (J2000 degrees,
equivalent to 15h 32m, 27d 36'), with an uncertainty
of 9.4 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees)
 
The angle from the Fermi LAT boresight is 49 degrees

The GBM light curve consists of two separate peaks,
the first from T0-0.768 to T0+0.768 sec and the second
from T0+24.0643 sec to T0+26.368 sec. T90 (8-1000 keV)
is about 27 sec. Both peaks were fit using a power-law function
with index -1.55 +/- 0.08 (chi squared 272.27/245 d.o.f.)
for the first and with index -1.55 +/- 0.07
(chi squared 249.72/245 d.o.f.)for the second peak.

The event fluence (8-1000 keV) for both peaks is
(2.1 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.768 s in the 8-1000 keV band
is 4.6 +/- 0.2 ph/s/cm^2

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090118A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8825
SUBJECT: GRB 090118: Possible burst detection from Swift-BAT slew data
DATE:    09/01/18 22:02:25 GMT
FROM:    Antonio Copete at Harvard U  <acopete@head.cfa.harvard.edu>

A. Copete, J. Grindlay (Harvard)
S. Barthelmy, C. Markwardt, N. Gehrels (NASA/GSFC)

We report the detection of a likely GRB candidate by the BAT Slew  
Survey (BATSS), pending confirmation by Swift XRT, in the slew that  
started at 13:54:02 UT and lasted 94 sec. The ground-calculated  
position is RA, Dec = 49.865, +18.478 deg, which is
RA (J2000) =  03h 19m 28s
Dec(J2000) = +18d 28' 40"
with an uncertainty of 3.69 arcmin (90% confidence, including  
systematics). The detection was triggered by simultaneous detections  
of 6.9 sigma and 8.0 sigma from imaging in the overlapping energy  
bands of 15-50 keV and 15-150 keV, respectively. The burst mask-tagged  
lightcurve in the 15-150keV band shows a broad emission peak starting  
at T+66 sec, lasting 19 sec, and peaking 3 times at T+71, T+74 and t+ T 
+81 sec. T90 = 16sec and T50 = 8sec.

The time-averaged spectrum over the exposure time of the source is  
best fit by a simple power law with photon index 1.35, and the fluence  
in the 15-150 keV band is 4.0 x 10^-7 erg/cm^2.

A follow-up Swift ToO observation has been scheduled to begin at 20:52  
UT, 6.97 hours after the burst. Optical/IR observers are encouraged to  
image this field as soon as possible as it is an early-evening object.


GRB_name: GRB090118A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8826
SUBJECT: GRB 090118: GROND Upper Limits
DATE:    09/01/19 02:23:14 GMT
FROM:    Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>

F. Olivares (MPE Garching), A. Rossi (Tautenburg Obs.), A. Kupcu Yoldas (ESO), J. Greiner, and A. Yoldas (both MPE Garching) report on behalf
of the GROND team:

We observed the field of the possible GRB 090118 (Swift BATSS trigger, Copete et al. GCN
#8825) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405)
mounted at the 2.2m MPI/ESO telescope at La Silla (Chile).
Observations started at 00:55 UT, about 11 hrs after the GRB.

Comparison to the Digital Sky Survey reveals no new sources within the Swift/BAT error circle
(Copete et al. GCN #8825). Co-added images of the first 8 minutes yield the following 5-sigma limits (in AB magnitudes):

r' > 23.2
i' > 22.5

The magnitudes are calibrated against SDSS.


GRB_name: GRB090118A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8827
SUBJECT: GRB090118 Swift/UVOT upper limits
DATE:    09/01/19 11:47:20 GMT
FROM:    Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>

P. Schady (MSSL-UCL) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began white-band observations of the field of the  
likely GRB candidate detected in the BAT Slew Survey (BATSS), GRB  
090118 (Copete et al., GCN 8825) at 2009-01-018 20:55:35 UT, 25.3 ks  
after the burst. We do not detect any new source within the Swift BAT  
error circle (Copete et al., GCN 8825) in a co-added white-band image  
down to the following 5-sigma upper limit:

Filter    T_start  T_stop  Exp         Mag
                (ks)       (ks)       (s)    (5-sigma upper limit)
-------------------------------------------------------------
white       25.3    35.3    1292     > 21.1
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected  
Galactic extinction along the line of sight of E_(B-V) = 0.13 mag. All  
photometry is on the UVOT photometric system described in Poole et al.  
(2008, MNRAS, 383, 627).


GRB_name: GRB090118A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8828
SUBJECT: GRB 090118: Swift-XRT observations
DATE:    09/01/19 17:41:00 GMT
FROM:    Antonia Rowlinson at U.of Leicester  <bar7@star.le.ac.uk>

GRB 090118: Swift-XRT observations

B.A. Rowlinson and K.L. Page (U. Leicester) report on behalf of the
Swift-XRT team:
 
Swift-XRT began a 6 ks follow-up ToO observation of the likely BAT
Slew Survey GRB 090118 (Copete et al., GCN Circ. 8825) 25.3 ks after the
start of the slew during which the burst was detected. No X-ray source
is detected within the 3.69 arcmin error circle, with a 3-sigma upper
limit
of 5.8x10^-3 count s^-1.
 
However, there is a source just outside the 90% error circle, at a
position of RA, Dec = 49.8276, 18.4148, which is equivalent to:
 
RA (J2000) = 03 19 18.62
Dec (J2000) = +18 24 53.3
 
with an uncertainty of 7.1 arcsec (radius, 90% confidence). This is a
distance of 260.9 arcsec from the BATSS position.This source has a
count rate of (9.0 +/- 2.2)x10^-3 count s^-1 in the first 1.6 ks of data
and appears to be fading to a count rate of (5.0 +/- 1.4)x10^-3 count
s^-1 in the last 4.2 ks of data.

A spectrum extracted for this source can be fitted with a power-law of
spectral index Gamma = 5.9 (+1.8, -1.4) with an absorbing column density
of 4.6 (+3.1, -2.2) x 10^21 cm^-2, in excess of/consistent with the
Galactic column in this direction of 8.9x10^20 cm^-2.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090118A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8829
SUBJECT: GRB 090118: KPNO 4m Detection of Candidate Afterglow
DATE:    09/01/19 21:29:12 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike and Dieter H. Hartmann (Clemson University) report:

Using the KPNO 4m telescope and the NEWFIRM instrument, we observed the
field of GRB 090118 (GCN 8825, Copete et al.) beginning 11.6 hours after
the burst in the J and H bands.  Within the XRT error circle (Rowlinson &
Page, GCN 8828) we detect a faint source at coordinates

RA   03:19:18.6
Dec +18:24:54.3

Variability has not been confirmed.  Further observations are planned.


Time after burst      Band     Magnitude
-------------------------------------------
11.6 hours             J       21.0 +/- 0.5
12.5 hours             H       20.2 +/- 0.4


A total of 40 minutes of exposures were taken in each band and the results
were stacked.  Magnitudes are calibrated to the 2MASS point source catalog
and against a nearby star (RA 03:19:16.7, Dec +18:25:14, J = 14.05).  No
correction has been made for galactic extinction.


GRB_name: GRB090118A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8830
SUBJECT: GRB 090118 (BATSS): GRT Optical Observation
DATE:    09/01/19 21:50:01 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <takanori.sakamoto-1@nasa.gov>

T. Sakamoto (UMBC/GSFC), D. Donato (ORAU/GSFC), N. Gehrels (GSFC),  
T. Okajima (JHU/GSFC), T. N. Ukwatta (GWU/GSFC), Y. Urata (Saitama U),  
C. Wallace (FGCU) 
  
We observed the field of the possible GRB 090118 detected by the BAT Slew Survey 
(Copete et al., GCN #8825) with the 14-inch Goddard Robotic Telescope (GRT) 
located at the Goddard Geophysical and Astronomical Observatory  
(http://cddisa.gsfc.nasa.gov/ggao/).   

Thirteen set of 30 sec and 60 sec exposures were taken in the R filter 
starting from Jan. 19 00:38:11 (UT) about 10.5 hr after the trigger.  We 
do not detect the optical afterglow both in the individual images and the 
combined image within the BATSS error circle and also the X-ray source 
found by the Swift/XRT (Rowlinson et al., GCN #8828).  
The estimated three sigma upper limit of the combined image (total 
exposure of 1170 sec) is ~17.6 mag using the USNO-B1 catalog. 


GRB_name: GRB090118A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8831
SUBJECT: GRB 090118: KPNO 4m 2nd Epoch Observations
DATE:    09/01/20 07:40:24 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike and Dieter H. Hartmann (Clemson University) report:

We observed the field of GRB 090118 (GCN 8825, Copete et al.) for a second
epoch beginning 36.7 hours after the burst.  Our observations consisted of
80 min of J band exposures.  In the stacked image, we still detect the
candidate (GCN 8829, Updike & Hartmann).  We re-analyzed our first epoch
image relative to 17 2MASS field stars, as well as our second epoch image.
 The brightness of the candidate source appears to be constant within
photometric uncertainties. While slow fading can't be ruled out, the
two-epoch results suggest that most likely the candidate source is
not the afterglow of GRB 090118. Third epoch observations are planned.


Time after burst     Band     Magnitude       Exp time
------------------------------------------------------
11.6 hours            J       21.2 +/- 0.6     40 min
36.7 hours            J       21.4 +/- 0.6     80 min


The images have been placed on the following site.

http://www.ces.clemson.edu/~aupdike/GRB090118/090118_J.jpg


GRB_name: GRB090118A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8832
SUBJECT: GRB 090118: Subaru NIR Observation
DATE:    09/01/20 11:02:37 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

Y. Minowa, T.-S. Pyo, H. Terada, K. Aoki (Subaru, NAOJ), and
N. Kawai (Tokyo Tech) report on behalf of the Subaru GRB team:

We observed the field of GRB 090118 (GCN 8825, Copete et al.) with
IRCS on the 8.2 m Subaru Telescope in J band beginning 39.2 hours 
after the burst (18 min exposure, mid-time 05:10 UT, Jan. 20).
The afterglow candidate reported by Updike et al. (GCN 8829, 8831)
was detected with J=21.3 mag, where the magnitude is estimated using
nearby 2MASS stars.


GRB_name: GRB090117C
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8836
SUBJECT: GRB 090117C: Suzaku WAM observation of the prompt emission
DATE:    09/01/22 12:37:45 GMT
FROM:    Kazutaka Yamaoka at Aoyama Gakuin U  <yamaoka@phys.aoyama.ac.jp>

M. Suzuki, M. Ohno, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. E. Nakagawa, T. Tamagawa (RIKEN), H. Hayashi, E. Sonoda, M. Yamauchi,
H. Tanaka, R. Hara, N. Ohmori, K. Kono (Univ. of Miyazaki), A. Endo,
M. Tashiro, Y. Terada, Y. Urata, K. Onda, N. Kodaka, K. Morigami,
T. Sugasahara, W. Iwakiri (Saitama U.), T. Enoto, K. Nakazawa,
K. Makishima (Univ. of Tokyo), S. Sugita, K. Yamaoka (Aoyama Gakuin U.),
Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira (Hiroshima U.), 
S. Hong (Nihon U.), N. Vasquez (Tokyo Tech.), on behalf of
the Suzaku WAM team, report:

The long GRB 090117C (Connaughton et al., GCN8822) triggered the
Suzaku Wide-band All-sky Monitor (WAM) which covers an energy
range of 50 keV - 5 MeV at 2009-01-17 15:10:40 UT (=T0).

The observed light curve shows relatively strong emission from
T0-6 s to T0+32 s with a precursor of about 1 min. long.
The duration (T90) including the precursor is about 91 seconds.
The fluence in 100 - 1000 keV was (1.18 +/- 0.11) x 10^-5 erg/cm^2.
The 1-s peak flux measured from T0+22 s was 1.2 (+/-0.3)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0-78 s
to T0+32 s is fitted by a single power-law with a photon index
of 1.72 +/- 0.18 (chi^2/d.o.f = 14/12).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB090118A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8840
SUBJECT: GRB 090118: Swift XRT Observations - Confirmation of an Afterglow
DATE:    09/01/22 20:14:14 GMT
FROM:    Antonia Rowlinson at U.of Leicester  <bar7@star.le.ac.uk>

B.A. Rowlinson and K.L. Page (U. Leicester) report of behalf of the
Swift-XRT team:

Swift-XRT completed a 10ks follow-up ToO obsevation of GRB 090118
(Copete et al. GCN Circ. 8825) approximately 250ks after the burst.
These observations confirm the previous Swift-XRT observations
(Rowlinson & Page GCN Circ. 8828) that a fading source has been detected
with a decay slope of alpha=0.61 +/- 0.3. This source is confirmed as
the afterglow.


GRB_name: GRB090123A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8842
SUBJECT: GRB 090123: Swift detection of a burst
DATE:    09/01/23 08:10:31 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

D. Grupe (PSU), P. A. Evans (U Leicester), C. Gronwall (PSU),
C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC),
J. L. Racusin (PSU), M. Stamatikos (NASA/ORAU) and L. Vetere (PSU)
report on behalf of the Swift Team:

At 07:51:56 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090123 (trigger=340895).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 6.775, -23.514 which is 
   RA(J2000) = 00h 27m 06s
   Dec(J2000) = -23d 30' 49"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 30 sec, beginning at about T-10 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 07:53:36.2 UT, 99.9 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 6.7863, -23.5007 which is equivalent to:
   RA(J2000)  = 00h 27m 08.71s
   Dec(J2000) = -23d 30' 02.5"
with an uncertainty of 5.1 arcseconds (radius, 90% containment). This
location is 60 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 107 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 00:27:08.74 =  6.78641
  DEC(J2000) = -23:30:03.9  = -23.50108
with a 90%-confidence error radius of about 0.75 arc sec. This position is 1.4
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.71 with a 1-sigma error of about 0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02. 

Burst Advocate for this burst is D. Grupe (grupe AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090123A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8843
SUBJECT: GRB090123: Enhanced Swift-XRT position
DATE:    09/01/23 12:50:55 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1885 s of XRT Photon Counting mode data and 1 UVOT
images for GRB090123, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 6.78599, -23.50156 which is equivalent
to:

RA (J2000): 00h 27m 8.64s
Dec (J2000): -23d 30' 05.6"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB090123A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8844
SUBJECT: GRB 090123: Swift-BAT refined analysis
DATE:    09/01/23 15:28:59 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. N. Ukwatta (GWU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
D. Grupe (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),
D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090123 (trigger #340895)
(Grupe, et al., GCN Circ. 8842).  The BAT ground-calculated position is
RA, Dec = 6.794, -23.503 deg, which is 
   RA(J2000)  =  00h 27m 10.5s 
   Dec(J2000) = -23d 30' 12.6" 
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 36%.
 
The mask-weighted light curve shows multiple overlapping peaks starting
at ~T-48 sec, with the max peak at ~T+3 sec, and ending at ~T+120 sec.
T90 (15-350 keV) is 131 +- 23 sec (estimated error including systematics).
 
The time-averaged spectrum from T-49.6 to T+117.9 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.74 +- 0.12.  The fluence in the 15-150 keV band is 2.9 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.08 sec in the 15-150 keV band
is 1.7 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/340895/BA/


GRB_name: GRB090123A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8846
SUBJECT: GRB 090123: Swift/UVOT Observations
DATE:    09/01/23 17:29:12 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F.E. Marshall (NASA/GSFC) and D. Grupe (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT observed the field of GRB 090123 starting 107 s after
the BAT trigger (Grupe et al., GCN Circ. 8842). We detect the optical
afterglow (Grupe et al.) in the white, v, b, u, uvw1, uvm2, and
uvw2 filters at the position:

  RA(J2000)  =  00:27:08.73 =   6.78639
  DEC(J2000) = -23:30:04.1  = -23.50113

with an estimated uncertainty of 0.5 arc sec. (radius, 90% confidence).
There is a broad peak in the light curve ~600 sec. after the trigger.
The 3.4-sigma detection in the uvw2 filter indicates that the redshift 
is less than ~1.4.

The magnitudes in the UVOT photometric system 
(Poole et al. 2008, MNRAS, 383, 627) in the first finding chart (FC) 
exposure and subsequent exposures are:

Filter          T_start(s)   T_stop(s)      Exp(s)       Mag 

white (FC)         107          257          147         17.8 +/- 0.1
v                  649          669           20         15.4 +/- 0.1
b                  575          595           20         15.8 +/- 0.1
u                  320          570          250         16.4 +/- 0.1
uvw1               698          718           20         17.3 +/- 0.23
uvm2              1251         8112          294         19.6 +/- 0.25
uvw2              1547         7843          413         20.5 +/- 0.29

The values quoted above are not corrected for the Galactic extinction due
to the reddening of E(B-V) = 0.02 in the direction of the burst 
(Schlegel et al. 1998).


GRB_name: GRB090123A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8847
SUBJECT: GRB 090123: Swift XRT refined analysis 
DATE:    09/01/23 19:21:36 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

D. Grupe (PSU) reports on behalf of the Swift-XRT team:

We have analyzed 7.7 ks of XRT data for GRB090123 (Grupe et al. GCN 
Circ. 8842),
beginning 106 s after the BAT trigger. The data comprise 334 s in Windowed
Timing (WT) mode with the remainder in Photon Counting (PC) mode.
The enhanced XRT position for this burst was given by Osborne et al.
(GCN. Circ 8843).

The light curve can be modeled with an initial power-law decay with an
index of alpha=1.78 (+0.06, -0.08), followed by a break at T+1530 
(+720,-220) s to
an alpha of 1.20 (+0.08, -0.10).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.65+/-0.05 with an absorption 
column fixed to the Galactic
value of 1.79 x 1020 cm-2 (Kalberla et al. 2005). The PC mode spectrum 
has a
photon index of 1.81+/-0.08 and an absorption column density also 
consistent
with the Galactic value.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.2 x 10-11 (4.5 x 10-11) erg cm-2 count-1.


If the light curve continues to decay with a power-law decay index of 1.20,
the count rate at T+24 hours will be 0.0031 counts/s, corresponding to an
observed (unabsorbed) 0.3-10 keV flux of 1.3 x 10-13 (1.4 x 10-13) erg cm-2
s-1.


GRB_name: GRB090123A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8849
SUBJECT: GRB 090123: GROND detection
DATE:    09/01/24 11:09:19 GMT
FROM:    Jochen Greiner at MPI  <jcg@mpe.mpg.de>

A. Rossi (Tautenburg Obs.) and J. Greiner (MPE Garching) report on behalf 
of the GROND team:

GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m ESO/MPI
telescope at La Silla Observatory (Chile) imaged the field of GRB 090123
(Swift trigger 340895, Grupe et al. 2009, GCN #8842) simultaneously in
g'r'i'z'JHK. Observation started on 2009-01-24 at 01:22 UTC, about 17 hours 
after the burst. The total exposure time was 25 minutes, the average seeing 
1.3 at airmass 2.5.

We detect the afterglow at the position reported by SWIFT UVOT (Marshall 
et al 2009, GCN #8846) in g'r'i'z', but not in JHK. We estimate the following 
observed magnitudes and upper limits (all in AB system):

g' = 22.77 +- 0.05
r' = 22.45 +- 0.05
i' = 21.95 +- 0.08
z' = 22.09 +- 0.12
J > 21.5
H > 21.0
K > 20.5

calibrated against GROND zeropoints and 2MASS field stars.


GRB_name: GRB090118A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8850
SUBJECT: GRB 090118: no afterglow candidate
DATE:    09/01/24 19:23:07 GMT
FROM:    Jochen Greiner at MPI  <jcg@mpe.mpg.de>

A. Rossi (Tautenburg Obs.), T. Kruehler, J. Greiner and F. Olivares 
(all MPE Garching), report on behalf of the GROND team:

We report on further analysis and new observations of the optical afterglow 
candidate of GRB 090118 (Copete et al. 2009, GCN #8825).

We re-analyzed our first epoch images (Olivares et al. 2009, GCN Circ. 8826),
taken at about 11 hrs after the GRB. No source is seen in our NIR images at 
the position of the X-ray afterglow (Rowlinson et al. 2008, GCN Circ. 8828),
giving upper limits (Vega system) of 

J > 20.6 
H > 19.6  
K > 18.7  

calibrated against 2MASS field stars.

The XRT position (Rowlinson et al. 2009, GCN  Circ. 8828) is outside of the 
field-of-view of the g'r'i'z' detectors, so no statement can be made on
the optical brightness during our first epoch.

We observed the field of GRB 090118 again with GROND on 2009-01-22 at a
mid-time of 01:30 UTC, about 100 hours after the burst. We clearly detect 
the candidate mentioned by Updike and Hartmann (2009, GCN Circ. 8829) in 
our optical filters, but not in the NIR:

g'= 23.46 +- 0.11 (AB)
r'= 23.27 +- 0.10 (AB)
i'= 22.95 +- 0.12 (AB)
z'= 22.25 +- 0.14 (AB)
J > 21.5 (Vega)
H > 20.5 (Vega)
K > 19.6 (Vega)

No correction for the foreground extinction of E(B-V)=0.135 mag
has been applied.

Comparing our g'r'i'z' values with the J and H detections of Updike & Hartmann 
(2009a; GCN Circ. 8829) and Minowa et al. (2009; GCN Circ. 8832) about two
days earlier, we find that the spectral energy distribution is smooth, thus 
supporting the non-fading nature of this object as indicated already by the
results of Updike & Hartmann (2009b; GCN Circ. 8831) and Minowa et al. 
(2009; GCN Circ. 8832).

The detection in g'r'i'z' implies that the object, whatever its nature, 
is at a redshift smaller than 3.5.

This excludes the possibility that this object is at high redshift and
exhibited a long plateau phase. The plateau phase would have to last more 
than 3 days in the NIR range, while at X-rays a steady decline has been 
seen (Rowlinson & Page 2009, GCN Circ. 8840). We conclude that this object 
is very likely not the optical/NIR afterglow of GRB 090118. Instead, the
object's SED is consistent with a low-redshift galaxy.


GRB_name: GRB090126A
Detection_method: superAGILE
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8852
SUBJECT: GRB 090126: SuperAGILE Localization of a Long GRB
DATE:    09/01/26 08:35:37 GMT
FROM:    Marco Feroci at IASF/INAF  <feroci@iasf-roma.inaf.it>

Y. Evangelista, E. Del Monte, I. Donnarumma, M. Feroci, F. Lazzarotto, L. 
Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda (INAF/IASF 
Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, 
F. Perotti, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. 
Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, 
(INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. 
Argan, A. Trois, G. Piano, S. Sabatini (INAF/IASF Rome), G. Barbiellini, 
F. Longo E. Moretti (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), 
M. Prest, E. Vallazza (Universita' dell'Insubria), P. Lipari, D. Zanello 
(INFN Roma-1), and P. Giommi, C. Pittori, B. Preger, P. Santolamazza, F. 
Verrecchia (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, 
report:

"SuperAGILE detected a gamma ray burst on 26 January 2009, at 02:01:15 UT.
The event had a duration of about 60 s in the 20-60 keV energy range,
with a structure composed of two separated main peaks. Assuming a 
Crab-like energy spectrum, the peak flux on 1-s timescale was 1.5E-07 
erg/cm2/s.
The burst position was reconstructed  as (RA, Dec)
(3.848 deg, 81.365 deg), which is:

RA(J2000)  = 00h 15m 23.50s
Dec(J2000) = 81d 21' 53.78"

with an uncertainty of 3' radius. The given uncertainty accounts
for both the statistical and systematic errors.

An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."

This message may be cited.


GRB_name: GRB090126B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8853
SUBJECT: GRB 090126B: Fermi GBM detection
DATE:    09/01/26 16:31:43 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 05:26:22.23 UT on 26 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090126B (trigger 254640384  / 090126227 ).

The on-ground calculated location, using the GBM trigger 
data, is RA = 190.5, DEC = 33.2  (J2000 degrees, 
equivalent to 19h 42m, 33d 12'), with an uncertainty 
of 4.4 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 18 degrees.

The GBM light curve consists of a single peak
with a duration (T90) of about 10.8 s (8-1000 keV). 
The time-averaged spectrum from T0-4.608 s to T0+5.632 s is 
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.99 +/- 0.18 and
the cutoff energy, parameterized as Epeak, is 47.5 +/- 3.4 keV
(chi squared 404.17 for 360 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(1.25 +/- 0.24)E-06 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0-0.512 s in the 8-1000 keV band 
is 4.9 +/- 1.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090126A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8854
SUBJECT: GRB 090126A: Swift-XRT Refined Analysis
DATE:    09/01/27 01:23:41 GMT
FROM:    Michael Stroh at PSU/Swift  <stroh@astroh.org>

M. C. Stroh (PSU) reports on behalf of the Swift-XRT team:

We have analyzed the first 3.1 ks of XRT data for GRB 090126A  
(Evangelista et al., GCN Circ. 8852), from T+48 ks to T+60 ks after  
the trigger. The data is all taken in Photon Counting (PC) mode.

Using 1435 s of XRT Photon Counting mode data and 2 UVOT images, we  
find an astrometrically corrected X-ray position (using the XRT-UVOT  
alignment and matching to the USNO-B1 catalogue): RA, Dec = 3.6577,  
81.3733 which is equivalent to:

RA (J2000): 00 14 37.85
Dec (J2000): +81 22 24.0

with an uncertainty of 2.2 arcsec (90% confidence).

This position may be improved as more data are received. The latest  
position can be viewed at http://www.swift.ac.uk/xrt_positions.  
Position enhancement is described by Goad et al. (2007, A&A, 476, 1401 http://www.swift.ac.uk/xrt_positions/Goad.pdf) 
, the current algorithm is an extension of this method.

A spectrum formed from the PC mode data can be fitted with an absorbed  
power-law with a photon spectral index of 1.8 (+0.6, -0.4). The best- 
fitting absorption column is 1.8 (+/- 1.8) x 10^21 cm^-2, which is  
consistent with the Galactic value of 1.4 x 10^21 cm^-2 (Kalberla et  
al. 2005). The observed (unabsorbed) flux in the 0.3-10.0 keV band is  
1.49 (1.9) x 10^-12 erg cm^-2 s^-1.

The light curve shows a potentially decaying source which can be fit  
using a single power-law decay with a slope, alpha = 1.2 (+/- 1.1).  
Assuming the light curve decays at the current rate, we predict count  
rates at T+24 and T+48 hours to be 1.6 x 10^-2 and 7.0 x 10^-3  
respectively.

This is an official product of the Swift-XRT team.


GRB_name: GRB090126C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8855
SUBJECT: GRB 090126C: Fermi GBM detection
DATE:    09/01/27 16:24:35 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 05:52:33.73 UT on 26 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090126C (trigger 254641955 / 090126245).

The on-ground calculated location, using the GBM trigger 
data, is RA = 222.9, DEC = 39.2 (J2000 degrees,        
equivalent to 14h 52m, 39d 12'), with an uncertainty 
of 14.6 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 68 degrees.

Since this GRB is weak and short (~ 1 sec), the time-averaged 
spectrum is poorly constrained."


GRB_name: GRB090102A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8856
SUBJECT: GRB 090102: HST observations and host galaxy
DATE:    09/01/27 22:33:21 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

A.J. Levan (Warwick), D. Malesani (DARK/NBI), N.R. Tanvir (Leicester),
A. Fruchter (STScI), J.P.U. Fynbo (DARK/NBI), J. Hjorth (DARK/NBI),
A. de Ugarte Postigo (ESO), P. Curran (MSSL), J. Graham (STScI),
K. Wiersema (U. Leicester) report:

We observed the afterglow of GRB 090102 (Mangano et al. GCN 8762;
Klotz et al. GCN 8761) using the Hubble Space Telescope and Wide Field
Planetary Camera on the 26th Jan 2009. Observations were obtained over
3 orbits (6400s), using the F606W filter. At the location of GRB 090102
we find an obvious host galaxy underlying the GRB afterglow. The magnitude
of the combined afterglow+ host at this time is R~24.5 (AB).

Astrometry utilizing early images obtained at the NOT (de Ugarte Postigo
et al GCN 8766) shows that the location of GRB 090102 is consistent with
the centroid of the galaxy/afterglow combined light (offset = 0.09 +/-
0.06").  This suggests that the afterglow may still be contributing
significantly at the current epoch. Estimates of the magnitude of any
likely point source coincident with this are inevitably uncertain, but do
allow for a continued decay with temporal index alpha~1. Later time
observations are planned, and will allow an accurate subtraction of the
host galaxy light.

Images can be found at

http://www.star.le.ac.uk/~anl/090102


GRB_name: GRB090129A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8861
SUBJECT: GRB 090129: Swift detection of a burst
DATE:    09/01/29 21:20:29 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. Ziaeepour (UCL-MSSL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
P.A. Curran (MSSL-UCL), P. A. Evans (U Leicester),
N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara), J. A. Kennea (PSU),
N. P. M. Kuin (MSSL), C. B. Markwardt (CRESST/GSFC/UMD),
P. T. O'Brien (U Leicester), C. Pagani (PSU),
K. L. Page (U Leicester), B. A. Rowlinson (U Leicester),
P. Schady (MSSL-UCL), M. Stamatikos (NASA/ORAU) and L. Vetere (PSU)
report on behalf of the Swift Team:

At 21:07:15 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090129 (trigger=341504). The BAT on-board calculated 
location is RA, Dec 269.092, -32.826 which is 
   RA(J2000) = 17h 56m 22s
   Dec(J2000) = -32d 49' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a FRED-like
structure with a duration of about 20 sec.  The peak count rate
was ~7000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to an observing constraint, Swift cannot slew to the BAT position. 
There will thus be no XRT or UVOT data for this trigger until
at least 03 Feb 2009. 

Burst Advocate for this burst is H. Ziaeepour (hz AT mssl.ucl.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090129A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8862
SUBJECT: GRB 090129: Swift-BAT refined analysis
DATE:    09/01/30 13:58:35 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU), H. Ziaeepour (UCL-MSSL)
(i.e. the Swift-BAT team):
 
Using the data set from T-120 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090129 (trigger #341504)
(Ziaeepour, et al., GCN Circ. 8861).  The BAT ground-calculated position is
RA, Dec = 269.105, -32.793 deg which is 
   RA(J2000)  =  17h 56m 25.1s 
   Dec(J2000) = -32d 47' 34.8" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 89%.
 
The mask-weighted light curve shows emission starting at ~T-30 sec,
then a large-amplitude FRED peak that returns to background at ~T+70 sec.
T90 (15-350 keV) is 17.5 +- 2.7 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.2 to T+27.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.88 +- 0.06.  The fluence in the 15-150 keV band is 2.1 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.00 sec in the 15-150 keV band
is 3.7 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/341504/BA/


GRB_name: GRB090126A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8864
SUBJECT: GRB 090126A: Swift/UVOT Upper Limits
DATE:    09/01/30 18:03:40 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <Stephen.T.Holland@nasa.gov>

S. T. Holland (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC), and
M. C. Stroh (PSU) report, on the behalf of the Swift/UVOT team:

      The Swift/UVOT observed the field of GRB 090126A (Evangelista
et al. 2009, GCN Circ. 8852) starting approximately 48 ks after the
SuperAGILE detection.  We find no new source, relative to the DSS or
USNO-B1.0 catalogue, or a variable source, inside the UVOT-enhanced
XRT error circle (Stroh et al. 2009, GCN Circ. 8854).  Preliminary
3-sigma upper limits for detecting a source in the co-added images,
using an aperture-corrected 2.5 arcsecond radius circular aperture,
are

Filter   T_start   T_stop    Exp(s)    Mag
------------------------------------------
  v      49,398   55,302      208   >20.1
  b      48,033   71,752     3256   >22.7
  u      47,960   71,155      333   >21.0
white    48,713   66,162     2022   >23.1
------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight corresponding to a
reddening of E_{B-V} = 0.20 mag (Schlegel et al., 1998, ApJS, 500,
525).  All photometry is on the UVOT photometry system described in
Poole et al. (2008, MNRAS, 383, 627).

Please update my e-mail address in your Address Book to <Stephen.T.Holland@nasa.gov 
 >.
/
\
/


GRB_name: GRB090201A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8865
SUBJECT: GRB 090201: Swift detection of a burst
DATE:    09/02/01 17:54:29 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
O. Godet (U Leicester), S. T. Holland (CRESST/USRA/GSFC),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
D. M. Palmer (LANL), P. Schady (MSSL-UCL) and H. Ziaeepour (UCL-MSSL)
report on behalf of the Swift Team:

At 17:47:02 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090201 (trigger=341749).  Swift could not immediately slew
due to the Earth limb constraint.  The BAT on-board calculated location is 
RA, Dec 92.031, -46.586 which is 
   RA(J2000) = 06h 08m 07s
   Dec(J2000) = -46d 35' 10"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multiple-peaked
structure with a duration of about 110 sec.  The peak count rate
was ~10000 counts/sec (15-350 keV), at ~7 sec after the trigger. 

Due to an observing constraint, Swift will not slew until 
T0+45.3 minutes. There will be no XRT or UVOT data until
this time. 

Burst Advocate for this burst is S. R. Oates (sro AT mssl.ucl.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090201A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8866
SUBJECT: GRB 090201: ROTSE-III Optical Limits
DATE:    09/02/01 19:01:36 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

B. E. Schaefer (Louisiana State) reports on behalf of the ROTSE 
collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,
responded to GRB 090201 (Swift trigger 341749; S. R. Oates et al., GCN
8865), producing images beginning 41 minutes after the burst trigger.  
Weather constraints in Namibia were the cause of the delay, as we had to
await the clearing of the skies.  Our first image was at 18:28:03.6 UT,
2460.9 s after the burst, under fair conditions. We took 10 5-sec, 10
20-sec and -8 60-sec exposures. These unfiltered images are calibrated
relative to USNO A2.0 (R). Imaging is on going.

Comparison to the DSS (second epoch) reveals no new sources within the
3-sigma Swift/BAT error circle, for both single images and coadding into
sets of 10; the field is not crowded.  Swift has not slewed to this burst
yet, so there is no XRT position to examine in detail.  Individual images
have limiting magnitudes ranging from 16.6-17.4; we set the following
specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
18:28:03.6   18:29:03.6        60     16.6         2460.9       N
18:28:03.6   18:30:15.5       131     16.9         2460.9       Y
18:42:25.4   18:54:11.1       705     18.2         3322.7       Y


GRB_name: GRB090113A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8867
SUBJECT: GRB090113: MAGIC telescope GeV observation
DATE:    09/02/01 19:34:26 GMT
FROM:    Markus Garczarczyk at MPI/MAGIC  <garcz@mppmu.mpg.de>

Becerra Gonzalez J. (IAC Tenerife), Gaug M. (IAC Tenerife), 
Antonelli L.A. (INAF Rome), Bastieri D. (Univ. Padova),
Becker J. (Univ. Dortmund), Carosi A. (INAF Rome),
Covino S. (INAF Rome), Galante N. (MPI Munich),
Garczarczyk M. (IFAE Barcelona), La Barbera A. (INAF Palermo),
Longo F. (INFN Trieste), Lorenz E. (ETH Zuerich),
Paoletti R. (Univ. Siena), Persic M. (INAF and INFN Trieste),
Scapin V. (Univ. Udine), Spiro S. (INAF Rome)
and Teshima M.(MPI Munich) for the MAGIC collaboration

The MAGIC Imaging Atmospheric Cherenkov Telescope performed a follow-up 
observation of the BAT burst GRB090113 (GCN circular 8804, Krimm et al.). 
We received the GCN alert at 18:41:01 UT (T0+20s), before the sunset. Data 
taking with MAGIC started at 20:06:08 UT (T0+4603s), when the GRB zenith 
angle reached 5 degrees. The observation continued for 9405 s.

No evidence for VHE gamma-ray emission above the analysis threshold of
94 GeV was found. The observation was carried out in (less sensitive) 
moon-observation mode from 21:39:01 UT on.

A preliminary analysis, for the hypothesis of steady emission and 
assumption of a differential photon spectral index of -2.5, yields the 
following 95% CL differential flux upper limits, including a 30% 
systematic uncertainty on the telescope efficiency.

E (  80- 125 GeV): 0.54 * 10^-10 erg cm^-2 s^-1
E ( 125- 175 GeV): 0.99 * 10^-10 erg cm^-2 s^-1
E ( 175- 300 GeV): 0.10 * 10^-10 erg cm^-2 s^-1
E ( 300-1000 GeV): 0.08 * 10^-10 erg cm^-2 s^-1
for a time window from 20:06:01 UT to 21:37:01 UT

E ( 125- 175 GeV): 0.93 * 10^-10 erg cm^-2 s^-1
E ( 175- 300 GeV): 0.23 * 10^-10 erg cm^-2 s^-1
E ( 300-1000 GeV): 0.08 * 10^-10 erg cm^-2 s^-1
for a time window from 21:39:01 UT to 22:32:01 UT

We can also exclude emission of a constant flux in any 100s time bin 
smaller than:

E (  80- 125 GeV): 13.89 * 10^-10 erg cm^-2 s^-1
E ( 125- 175 GeV): 8.88 * 10^-10 erg cm^-2 s^-1
E ( 175- 300 GeV): 3.40 * 10^-10 erg cm^-2 s^-1
E ( 300-1000 GeV): 1.22 * 10^-10 erg cm^-2 s^-1
for a time window from 20:06:01 UT to 21:37:01 UT

E ( 125- 175 GeV): 13.20 * 10^-10 erg cm^-2 s^-1
E ( 175- 300 GeV): 3.88 * 10^-10 erg cm^-2 s^-1
E ( 300-1000 GeV): 2.30 * 10^-10 erg cm^-2 s^-1
for a time window from 21:39:01 UT to 22:32:01 UT

This message can be cited.


GRB_name: GRB090201A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8868
SUBJECT: GRB 090201: Swift-XRT detection of the possible X-ray afterglow
DATE:    09/02/01 19:35:30 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A.P. Beardmore and K.L. Page (U. Leicester) report on behalf of the
Swift-XRT team :

The Swift-XRT started observing the field of GRB 090201 (Oates et al,
GCN Circ. 8865) in photon counting mode at 18:50:40.7UT, 63.6 minutes
after the trigger. In 1.4 ks of promptly downlinked data we detect
a source at a position of RA, Dec = 92.0530, -46.5888, which is

RA (J2000)  =   06h 08m 12.74s
Dec (J2000) =  -46d 35m 19.8s

with an uncertainty of 3.5 arcsec (radius, 90% containment). The source is
55.5 arcsec from the  reported BAT position and within its error circle.
We do not have sufficient data at this stage to tell if the source is
fading.


GRB_name: GRB090201A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8869
SUBJECT: GRB 090201: VLT afterglow candidate
DATE:    09/02/02 01:54:09 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

"P. D'Avanzo, C. C. Thoene, D. Fugazza (INAF-OAB), V. D'Elia (INAF-OAR), 
R. Salvaterra, S. Covino, S. Campana (INAF-OAB), G. Chincarini (Univ. 
Bicocca) report, on behalf of the MISTICI collaboration:

We observed the field of GRB 090201 (Oates et a., GCN 8865) with the 
ESO-VLT in imaging mode starting about 7.5 hours after the burst. 
Observations were carried out in R and I-band with the FORS2 camera.

At the edge of the XRT error circle (Beardmore et al. GCN 8868) we find 
a very faint source at the following coordinates (J2000):

R.A. = 06:08:12.92
Dec. = -46:35:17.3

+/- 0.3"

Preliminary photometry of this candidate afterglow gives R ~ 25.2 and I 
~ 24.1. Further observations are ongoing.


We acknowledge the VLT staff for their support, in particular E. Valenti 
and J. Smoker.

[GCN OPS NOTE(02jan09): Per author's request, RS was added to the author list.]


GRB_name: GRB090201A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8870
SUBJECT: GRB 090201: Swift-BAT refined analysis
DATE:    09/02/02 04:13:21 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), S. R. Oates (UCL-MSSL), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+363 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 090201 (trigger #341749)
(Oates, et al., GCN Circ. 8865).  The BAT ground-calculated position is
RA, Dec = 92.051, -46.604 deg, which is 
   RA(J2000)  =  06h 08m 12.3s 
   Dec(J2000) = -46d 36' 16.1" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 8%.
 
The mask-weighted light curve shows two clusters of overlapping peaks.
The first starting at ~T-20 sec and peaking at ~T+8 sec.  The second peaks
at ~T+39 sec and ends at ~T+120 sec.  T90 (15-350 keV) is 83 +- 4 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-10.2 to T+102.2 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.88 +- 0.18, 
and Epeak of 104 +- 16 keV (chi squared 39.5 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 3.0 +- 0.1 x 10^-5 erg/cm2
and the 1-sec peak flux measured from T+7.60 sec in the 15-150 keV band is
14.7 +- 1.0 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.50 +- 0.04 (chi squared 76.3 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/341749/BA/


GRB_name: GRB090201A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8871
SUBJECT: GRB 090201: VLT NIR observations
DATE:    09/02/02 04:51:55 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, C. C. Thoene, D. Fugazza (INAF-OAB), V. D'Elia, S. 
Piranomonte (INAF-OAR), R. Salvaterra, S. Covino, S. Campana (INAF-OAB), 
G. Chincarini (Univ. Bicocca) report, on behalf of the MISTICI 
collaboration:

We continued observing the field of GRB 090201 (Oates et a., GCN 8865) 
with the ESO-VLT in imaging mode with the ISAAC NIR camera. Observations 
were carried out in J, H and K-band about 9.5 hours after the burst.

The optical afterglow candidate (D'Avanzo et al. GCN 8869) is not 
visible in the coadded images down to the following upper limits (3sigma 
c.l.): J = 23.0, H = 22.4, K = 21.1 (calibrated against the 2MASS 
catalogue).

The absence of a NIR detection suggests that the object observed by 
D'Avanzo et al. (GCN 8869) is not the optical afterglow of GRB 090201 
but probably a field galaxy. Further analysis is in progress.

We acknowledge the VLT staff for their support, in particular E. Valenti 
and J. Smoker.


GRB_name: GRB090201A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8872
SUBJECT: GRB 090201: Enhanced Swift-XRT position
DATE:    09/02/02 04:52:21 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 3196 s of XRT Photon Counting mode data and 8 UVOT
images for GRB 090201, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 92.05202, -46.59045 which is equivalent
to:

RA (J2000): 06h 08m 12.48s
Dec (J2000): -46d 35' 25.6"

with an uncertainty of 1.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB090201A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8873
SUBJECT: GRB 090201: object inside the enhanced XRT error circle
DATE:    09/02/02 05:29:17 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, C. C. Thoene, D. Fugazza (INAF-OAB), V. D'Elia, S. 
Piranomonte (INAF-OAR), R. Salvaterra, S. Covino, S. Campana (INAF-OAB), 
G. Chincarini (Univ. Bicocca)  report, on behalf of the MISTICI 
collaboration:

Following the enhanced XRT position (Beardmore et al. GCN 8872) we 
re-analyzed our VLT optical and NIR images of the field of GRB 090201 
(D'Avanzo et al. GCNs 8869, 8871). We find an object at the following 
coordinates (J2000):

R.A. = 06:08:12.48
Dec. = -46:35:24.2

+/- 0.5"

consistent with the enhanced XRT position. Preliminary photometry of 
this object gives R ~ 24.6 and J ~ 21.8. The moderate red color suggests 
that this object likely is the afterglow of
GRB 090201.

Further observations are ongoing.


GRB_name: GRB090201A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8874
SUBJECT: GRB090201: Swift UVOT upper limits
DATE:    09/02/02 11:05:00 GMT
FROM:    Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>

P. Schady (MSSL-UCL) and S. Oates (MSSL-UCL) report on behalf of the  
Swift UVOT team

The Swift/UVOT began settled observations of the field of GRB 090201  
3668s after the BAT trigger (Oates et al., GCN 8865). We do not detect  
any source at the enhanced Swift XRT position (Beardmore et al. GCN  
8872) or at the VLT optical and NIR afterglow candidate (D'Avanzo et  
al. GCN 8873) down to the following 3-sigma upper limits:

Filter    T_start(s)   T_stop(s)  Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
White     3668           5051       344       > 21.53
v             3825          10589      1159    > 20.63
b             4646          16906      834      > 21.38
u             4440          16245      1082    > 21.15
uvw1      4235          14730      448      > 20.16
uvm2     4030           11123     717       > 20.53
uvw2      5056          5256        197       > 20.03

The quoted upper limits have not been corrected for the expected  
Galactic extinction along the line of sight of E_(B-V) = 0.07 mag. All  
photometry is on the UVOT photometric system described in Poole et al.  
(2008, MNRAS, 383, 627).


GRB_name: GRB090201A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8875
SUBJECT: GRB 090201: Swift-XRT refined analysis
DATE:    09/02/02 11:12:04 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A.P. Beardmore, K.L. Page (U. Leicester), S.R. Oates (UCL-MSSL) report on
behalf of the Swift-XRT team.

The Swift-XRT started observing the BAT GRB 090201 (trigger #341749,
Oates et al., GCN circ. 8865) at 18:47:33 UT, 3.65ks after the trigger.
The UVOT-enhanced X-ray position has been reported in Beardmore et al.
(GCN Circ. 8872).

Using 14.5ks of photon counting mode data taken from T+3.65ks to T+39.2ks
after the trigger, we find the X-ray light curve can be described by a
broken powerlaw, with initial decay slope of 0.64 +0.17 -0.15, break time
of 7.2 +2.1 -1.5 ks and final decay slope of 1.45 +/- 0.11.

The spectrum spanning the same interval can be fit by an absorbed
powerlaw, with a photon index of 2.20 +/- 0.10 and column density of
4.78 +/- 0.42 x 10^21 cm^-2, compared with the Galactic column of 4.9
x 10^20 cm^-2 in the direction of the burst. The observed (unabsorbed)
0.3-10 keV flux is (1.00 +/- 0.06) x 10^-11 [(2.02+/-0.12) x 10^-11]
erg cm^-2 s^-1.

Assuming the decay continues at the same rate, we  predict a count rate
of 0.017 count/s 1 day after the trigger, which corresponds to an observed
0.3-10 keV flux of 7.4e-13 erg cm^-2 s^-1.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090131A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8876
SUBJECT: GRB 090131: Fermi GBM detection
DATE:    09/02/03 03:23:47 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (UAH) and A.J. van der Horst (NASA/MSFC/ORAU) report 
on behalf of the Fermi GBM Team: 

"At 02:09:21.15 UT on 31 January 2009, the Fermi Gamma-Ray Burst Monitor 
triggered and located GRB 090131 (trigger 255060563 / 090131090).

The on-ground calculated location, using the GBM trigger data, is 
RA = 353.0, DEC = +16.4 (J2000 degrees, equivalent to 23h 32m, 16d 26'), 
with a statistical uncertainty of less than 1 degree (radius, 1-sigma 
containment) and an additional systematic error which is currently 
estimated to be 2 to 3 degrees.
The angle from the Fermi LAT boresight is 40 degrees.

The GBM light curve consists of two emission pulses, each with 
substructure and separated by a period of no significant 
emission above background.  The total duration (T90) is about 
36.4 s (8-1000 keV).  The time-averaged spectrum from T0+0.0 s to 
T0+42.2 s is best fit by a Band function with 
Epeak = 58.4 +/- 3.9 keV, alpha = -1.27 +/- 0.07, and 
beta = -2.26 +/- 0.05 (chi-square 597.4 for 453 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(2.23 +/- 0.17)E-05 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+6.4 s in the 8-1000 keV band 
is 47.9 +/- 10.0 ph/s/cm^2.

The spectral and temporal analysis results presented above are 
preliminary; final results will be published in the GBM GRB Catalog."


GRB_name: GRB090202A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8877
SUBJECT: GRB 090202: Fermi GBM detection
DATE:    09/02/03 10:14:37 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 08:19:30.40 UT on 02 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090202 (trigger 255255572 / 090202347).
The on-ground calculated location, using the GBM trigger 
data, is RA = 268.9, DEC = -2.5 (J2000 degrees, 
equivalent to 17h 56m, -02d 30'), with an uncertainty  
of 2.3 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 55 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve shows a single peak and a tail
with a duration (T90) of about 66 s (8-1000 keV). 
The time-averaged spectrum from T0-1.536 s to T0+15.872 s is
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.31 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 570 +/- 170 keV
(chi squared 510.50 for 485 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(8.65 +/- 0.31)E-06 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+8.704 s in the 8-1000 keV band 
is 7.77 +/- 0.41 ph/s/cm^2.

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090201A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8878
SUBJECT: Konus-Wind observation of GRB 090201
DATE:    09/02/03 12:27:16 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The long GRB 090201 (Swift-BAT trigger #341749: Oates et al., GCN
8865; Baumgartner et al., GCN 8870)
triggered Konus-Wind at T0=64020.275 s UT  (17:47:00.275).

The burst light curve shows a multipeaked structure with a duration of
~110 s.

As observed by Konus-Wind the burst
had a fluence of 6.72(-0.54, +0.47)x10^-5 erg/cm2,
and a 64-ms peak flux measured from T0+11.728 s
of 7.30(-1.28, +1.24)x10^-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+107.520 s) is well fitted (in the 20 keV - 2 MeV
range) by GRB (Band) model for which:
the low-energy photon index is alpha = -0.97(-0.09, +0.10),
the high energy photon index beta = -2.80(-0.92, +0.29),
the peak energy Ep = 158(-12, +13) keV (chi2 = 51.0/59 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB090201_T64020/


GRB_name: GRB090126A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8880
SUBJECT: GRB 090126A: Swift-XRT afterglow confirmation
DATE:    09/02/03 16:43:33 GMT
FROM:    Michael Stroh at PSU/Swift  <stroh@astroh.org>

M. C. Stroh (PSU) reports on behalf of the Swift-XRT team:

Swift took an additional 7.6ks observation of GRB 090126A centered at T 
+29ks after the trigger. The single uncatalogued X-ray source  
previously reported by Stroh et al. (GCN Circ. 8854) shows fading  
flux, confirming its afterglow nature.

The 0.3-10 keV light curve can be fit using a simple power law model  
with decay index alpha = 1.42 +/- 0.13.

This is an official product of the Swift-XRT team.


GRB_name: GRB090131A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8882
SUBJECT: GRB 090131: Suzaku WAM observation of the prompt emission
DATE:    09/02/05 01:05:13 GMT
FROM:    Yoshitaka Hanabata at Hiroshima U  <hanabata@hep01.hepl.hiroshima-u.ac.jp>

Y. Hanabata, Y. Fukazawa, T. Takahashi, T. Uehara, C. Kira (Hiroshima U.),
Y. Terada, M. Tashiro, Y. Urata, A. Endo, K. Onda, N. Kodaka,
K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), M. Ohno,
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), K. Yamaoka,
S. Sugita (Aoyama Gakuin U.), T. Enoto, K. Nakazawa, K. Makishima
(Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori, K. Kono,
H. Hayashi (Univ. of Miyazaki), S. Hong (Nihon U.),
N. Vasquez (Tokyo Tech), on behalf of the Suzaku WAM team, report:

The long GRB 090131 (Goldstein et al., GCN 8876) triggered the
Suzaku Wide-band All-sky Monitor (WAM) which covers an energy
range of 50 keV - 5 MeV at 2009-01-31 02:09:24.187 UT (=T0).

The observed light curve shows a multi-peaked structure starting at T0-5s,
ending at T0+46s with a duration (T90) of about 32.6 seconds. The fluence in
100 - 1000 keV was 9.95(-0.59, +0.57) x 10^-6 erg/cm^2. The 1-s peak
flux measured from T0+19s was 5.01(-0.39, +0.35) photons/cm^2/s in the
same energy range.

Preliminary result shows that the time-averaged spectrum from T0-5s
to T0+46s is fitted by a single power-law with a photon index
of 2.29(-0.15, +0.17) (chi^2/d.o.f = 11.4/13).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8883
SUBJECT: GRB 080319B: IceCube upper limit on high-energy neutrino flux
DATE:    09/02/05 17:41:59 GMT
FROM:    Alexander Kappes at UW-Madison/IceCube  <alexander.kappes@icecube.wisc.edu>

Alexander Kappes for the IceCube collaboration (http://www.icecube.wisc.edu 
) reports:

IceCube is a 1 km^3 neutrino telescope located at the geographic South  
Pole sensitive to neutrinos above ~100 GeV. We used the data from  
IceCube in its 9-string configuration to search for high-energy muon  
neutrinos from the position of GRB 080319B (Racusin et al., GCN 7427)  
using an unbinned likelihood method. The search was performed in a  
narrow time window of 66 s (T_0 - 3.8s to T_0 + 62.2s) corresponding  
to the observed prompt gamma-ray emission, and in a wider window of  
about 5 minutes (T_0 - 173s to T_0 + 130 s).

We do not find any indications for a deviation from the background- 
only hypothesis in either of the two time windows. Therefore, we use  
the null result from the prompt window to place an upper limit (90%  
C.L.) on the prompt muon neutrino flux from GRB 080319B of 9.0e-3 erg  
cm^-2 in the energy range between 145 TeV and 2.1 PeV.

A corresponding paper has been submitted to ApJ. The preprint version  
can be found at arXiv:0902.0131.


GRB_name: GRB090205A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8884
SUBJECT: GRB 090205: Swift detection of a burst
DATE:    09/02/05 23:17:10 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. Perri (ASDC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
N. Gehrels (NASA/GSFC), O. Godet (U Leicester), C. Gronwall (PSU),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
W.B Landsman (GSFC), C. B. Markwardt (CRESST/GSFC/UMD),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL),
M. Stamatikos (NASA/ORAU), G. Stratta (ASDC), M. C. Stroh (PSU) and
L. Vetere (PSU) report on behalf of the Swift Team:

At 23:03:14 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090205 (trigger=342121).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 220.925, -27.864 which is 
   RA(J2000) = 14h 43m 42s
   Dec(J2000) = -27d 51' 48"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single peak
with a duration of about 10 sec.  The peak count rate
was ~900 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 23:04:42.4 UT, 87.6 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 220.91150, -27.85298 which is
equivalent to:
   RA(J2000)  = 14h 43m 38.76s
   Dec(J2000) = -27d 51' 10.7"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 58 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
7.72e+20 cm^-2 (Kalberla et al. 2005). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 92 seconds after the BAT trigger. No credible
afterglow candidate has  been found in the initial data products. 
The 8'x8' region for the list of sources generated on-board covers
100% of the BAT error circle and 100% of the XRT error circle.   The
list of sources is typically complete to about 18 mag. No correction
has been made for the expected extinction corresponding to E(B-V) of
0.12. 

Burst Advocate for this burst is M. Perri (perri AT asdc.asi.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090205A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8885
SUBJECT: GRB 090205: Enhanced Swift-XRT position
DATE:    09/02/06 02:40:31 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 944 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 090205, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 220.91119, -27.85267 which is equivalent
to:

RA (J2000): 14h 43m 38.69s
Dec (J2000): -27d 51' 09.6"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB090205A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8886
SUBJECT: GRB 090205: Swift-BAT refined analysis
DATE:    09/02/06 03:30:35 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

GRB 090205: Swift-BAT refined analysis
 
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), M. Perri (ASDC),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+455 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090205 (trigger #342121)
(Perri, et al., GCN Circ. 8884).  The BAT ground-calculated position is
RA, Dec = 220.917, -27.848 deg which is 
   RA(J2000)  =  14h 43m 40.0s 
   Dec(J2000) = -27d 50' 51.4" 
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted light curve shows a single peak starting at ~T-5 sec,
peaking at ~T+3 sec, and returning to background at ~T+100 sec.
T90 (15-350 keV) is 8.8 +- 1.8 sec (estimated error including systematics).
 
The time-averaged spectrum from T-2.9 to T+6.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.15 +- 0.23.  The fluence in the 15-150 keV band is 1.9 +- 0.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+4.09 sec in the 15-150 keV band
is 0.5 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/342121/BA/


GRB_name: GRB090205A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8887
SUBJECT: GRB 090205: VLT candidate afterglow
DATE:    09/02/06 07:20:57 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, C. C. Thoene, D. Fugazza (INAF-OAB), V. D'Elia, S.  
Piranomonte (INAF-OAR), R. Salvaterra, S. Covino, S. Campana (INAF-OAB), 
G. Chincarini (Univ. Bicocca) report, on behalf of the MISTICI 
collaboration:

We observed the field of GRB 090205 (Perri et al., GCN 8884) with the 
ESO-VLT in imaging mode starting about 7.1 hours after the burst. 
Observations were carried out in R and I-band with the FORS1 camera.

Inside the enhanced XRT error circle (Evans et al. GCN 8885) we find a 
source at the following coordinates (J2000):

R.A. = 14:43:38.65
Dec. = -27:51:10.7

+/- 0.4"

Preliminary photometry of this candidate afterglow gives R ~ 22.0 .


We acknowledge the VLT staff for their support, in particular G. James 
and J. Smoker.


GRB_name: GRB090205A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8888
SUBJECT: GRB 090205: GROND observations and photometric redshift estimate
DATE:    09/02/06 07:26:53 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

T. Kruehler and J.Greiner (both MPE Garching) report on behalf of the
GROND team:

We observed the field of GRB 090205 (Swift trigger 342121, M. Perri et
al.,GCN #8884) simultaneously in g'r'i'z'JHK with GROND mounted at the
2.2m ESO/MPI telescope at La Silla Observatory (Chile).

Observations started on 03 Feb. 2009 at 05:25 UT, 6.33 h after the burst.

The object reported by D'Avanzo et al. (GCN #8887) is very well detected
in the i' band and redder, marginally in r' and not in g'. A preliminary
i' band magnitude is 20.7 +- 0.2 roughly 7 hours after the burst.
Interpreting the large r'-i' color and the g' band non detection as
Lyman-alpha absorption in the GRB host, we derive a photometric redshift
of 4.7 +- 0.3. This redshift estimate has been obtained using hyperZ
(Bolzonella et al. 2000). We caution that this is based on a preliminary
calibration.

No statement about variability can be made at this point.

[GCN OPS NOTE(06feb09): Per author's request, date and time in the sentence
in the second paragraph were changed from "03 Feb" to "06 Feb"
and from "05:25" to "05:23".]


GRB_name: GRB090205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8889
SUBJECT: GRB 090205: VLT spectroscopic redshift
DATE:    09/02/06 08:57:35 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

C. C. Thoene, D. Fugazza, P. D'Avanzo (INAF-OAB), V. D'Elia, S. 
Piranomonte (INAF-OAR), R. Salvaterra, S. Covino, S. Campana (INAF-OAB), 
G. Chincarini (Univ. Bicocca) report, on behalf of the MISTICI 
collaboration:

We observed the optical afterglow of GRB 090205 (D'Avanzo et al. GCN 
8887; Kruehler & Greiner GCN 8888) with the ESO VLT about 9.0 hours 
after the burst with the FORS1 camera in spectroscopic mode. We took a 
20 min spectrum covering the range 4000-9000 Angstrom (based on a 
preliminary wavelength calibration) with a resolution of R=440.

We detect a broad absorption feature around lambda_obs = 6800 Angstrom. 
Interpreting this feature as Ly-alpha absorption the inferred redshift 
is z = 4.6 in agreement with the photometric redshift reported by 
Kruehler & Greiner (GCN 8888).

We acknowledge excellent support from the ESO staff, in particular G. 
James and J. Smoker.


GRB_name: GRB090205A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8890
SUBJECT: GRB 090205:  Swift burst of interest
DATE:    09/02/06 14:46:05 GMT
FROM:    Neil Gehrels at GSFC  <cornelis.a.gehrels@nasa.gov>

N. Gehrels (GSFC) & M. Perri (ASDC) report on behalf of the Swift team

Based on its high redshift, relatively bright optical afterglow and
variable X-ray afterglow, the Swift team declares GRB 090205
to be a burst of interest to be followed by Swift as long as
detectable.  We encourage ground-based follow-ups.  Please
post your results / plans or send us informal information to
help with observation planning.


GRB_name: GRB090205A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8891
SUBJECT: GRB 090205: Swift-XRT refined analysis
DATE:    09/02/06 15:58:50 GMT
FROM:    Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>

M. Perri and G. Stratta (ASDC) report on behalf of the Swift XRT team:

We have analyzed the first 13.5 ks of Swift-XRT data of the BAT GRB
090205 (Perri et al., GCN Circ. 8884). The data, starting at 2009-02-05
23:04:55 UT and ending at 2009-02-06 09:10:33 UT, is all taken in
Photon Counting (PC) mode.

The best XRT position is the UVOT-enhanced position reported by
Evans et al. (GCN Circ. 8885).

In the time interval T+94s-T+580 s the X-ray light curve can be modeled by
a simple power law with a decay index alpha_1= 1.4  0.3 (90% confidence)
followed by a re-brightening around T+1 ks. After the re-brightnening,
from T+5 ks up to T+30 ks, the light curve decays with a power law
index alpha_2= 0.9  0.2.

The X-ray spectrum is well fit by an absorbed power-law model
with a photon index of 2.0 (+/-0.2) and a column density consistent
with the Galactic one in the direction of the source (7.7e20 cm**-2,
Kalberla et al. 2005). The estimated 3-sigma (2-sigma) upper limit on the
intrinsic column density at z=4.6 (Thoene et al., GCN Circ. 8889) is
4.1e22cm**-2 (2.8e22cm**-2).

Assuming the X-ray emission continues to decline at the same rate, we
predict a 0.3-10 keV XRT count rate of 6e-3 count/s at T+24hr, which
corresponds to an observed 0.3-10 keV flux of ~2e-13 erg/cm**2/s.

This circular is an official product of the Swift-XRT Team.


GRB_name: GRB090205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8892
SUBJECT: GRB 090205: VLT refined redshift 
DATE:    09/02/06 16:23:14 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

D. Fugazza, C. C. Thoene (INAF-OAB), V. D'Elia (INAF-OAR), P. D'Avanzo 
(INAF-OAB), S. Piranomonte (INAF-OAR), R. Salvaterra, S. Covino, S. 
Campana (INAF-OAB), G. Chincarini (Univ. Bicocca) report, on behalf of 
the MISTICI collaboration:

We performed further analysis of our VLT spectrum of the optical 
afterglow of GRB 090205 (D'Avanzo et al. GCN 8887; Kruehler & Greiner, 
GCN 8888; Thoene et al., GCN 8889).

We clearly detect the following absorption features: Ly_alpha (1215.67), 
SiII (1260.66), SiII (1303.27), CII (1334.53), SiIV (1393.76, 1402.77) 
doublet, SiII (1526.71) and CIV (1548.20,1550.77) doublet at a redshift 
of z = 4.6497  0.0025 consistent with previous claims (Kruehler & 
Greiner, GCN 8888; Thoene et al., GCN 8889).


GRB_name: GRB090205A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8893
SUBJECT: GRB 090205: Swift/UVOT Upper Limits
DATE:    09/02/06 16:54:59 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W. Landsman (NASA/GSFC) and M. Perri (ASDC) report on behalf of the 
Swift UVOT team

The Swift/UVOT began settled observations of the field of GRB 090205 92s 
after the BAT trigger (Perri et al., GCN 8884). We do not detect any 
source at the enhanced Swift XRT position (Evans et al. GCN 8885) or at 
the VLT optical candidate position (D'Avanzo et al. GCN 8887).     The 
UVOT non-detections are consistent with the spectroscopic redshift of 
4.6 reported by Thoene et al. (GCN 8889).    Our 3-sigma upper limits 
are reported below.

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white       92       242     148       > 21.1
white       92      7633     824       > 21.9
v          580     12829    1234       > 20.7
b          506     34930    2073       > 21.7
u          250       500     246       > 20.5
u          298     18581    1660       > 21.4
uvw1       629     17668    1415       > 21.4
uvm2       604     23148    1882       > 21.4
uvw2       555     11915    1322       > 21.5

The quoted upper limits have not been corrected for the expected 
Galactic extinction along the line of sight of E_(B-V) = 0.12 mag.   All 
photometry is on the UVOT photometric system described in Poole et al. 
(2008, MNRAS, 383, 627).


GRB_name: GRB090205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8895
SUBJECT: GRB 090205: VLT optical decay
DATE:    09/02/07 09:35:05 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, D. Fugazza (INAF-OAB), V. D'Elia (INAF-OAR), R. Salvaterra, 
C. C. Thoene (INAF-OAB), S.  Piranomonte (INAF-OAR), S. Covino, S. 
Campana (INAF-OAB), G. Chincarini (Univ. Bicocca) report, on behalf of 
the MISTICI collaboration:

We continued monitoring GRB 090205 (Perri et al., GCN 8884) with the 
ESO-VLT in imaging mode. Observations were carried out in R-band with 
the FORS1 camera about 1.35 days after the burst.

Preliminary analysis of a first set of images (total exposure: 12 min) 
reveals that the optical afterglow (D'Avanzo et al. GCN 8887; Kruehler & 
Greiner GCN 8888) is still detected and that it faded by about 3 mags 
with respect to our previous epoch of VLT observations (D'Avanzo et al. 
GCN 8887). Assuming a power-law decy, the inferred decay index between 
this two epochs is alpha ~ 1.8, steeper than what measured in the X-rays 
at earlier epochs (Perri & Stratta, GCN 8891). Further optical 
observations are ongoing.


We acknowledge the VLT staff for their support, in particular G. James 
and L. Schmidtobreick.


GRB_name: GRB090205A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8896
SUBJECT: VLA radio upper limit on GRB 090205
DATE:    09/02/07 14:57:15 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on
behalf of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward
GRB 090205 (GCN 8884) at a frequency of 8.46 GHz on 2009 Jan 07.50
UT. The GRB radio afterglow is undetected at 3-sigma level. The
flux density at the VLT afterglow position (GCB 8887) is 21  47 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB090129A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8897
SUBJECT: GRB 090129: Fermi GBM detection
DATE:    09/02/09 17:17:37 GMT
FROM:    Sylvain Guiriec at UAH  <sylvain.guiriec@lpta.in2p3.fr>

S. Guiriec (UAH) reports on behalf of the Fermi GBM Team:

"At 21:07:15.42 UT on 29 January 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090129 (trigger 254956037 / 090129880) which was
also detected by the SWIFT-BAT.
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 22 degrees.

The GBM light curve consists of a single peak with a FRED shape starting at
~T0-0.3s with a duration (T90) of about 17.2s (8-1000 keV).
The time-averaged spectrum from T0-0.3s to T0+15.1s is well fitted by a
Band function with Epeak = 123.2 +/- 44.8 keV, alpha = -1.39 +/- 0.13,
and beta = -1.98 +/- 0.14 (chi squared 373 for 374 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(5.6 +/- 0.7)E-06 erg/cm^2.
The 1-sec peak photon flux measured starting from T0+0.8 s in the
8-1000 keV band is 8.0 +/- 0.1 ph/s/cm^2.

The spectral and temporal analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090207A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8899
SUBJECT: GRB 090207 - Fermi GBM Observations
DATE:    09/02/10 18:35:46 GMT
FROM:    Narayana Bhat at U Alabama/Huntsville/GBM  <Narayana.Bhat@nasa.gov>

P. N. Bhat (UAH) 
reports on behalf of the Fermi GBM Team:

"At 18:39:10.84 UT on 07 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090207 (trigger 255724752 / 090207777).

The on-ground calculated location, using the GBM trigger
data, is RA = 244.66, DEC = +36.81 (J2000 degrees,
equivalent to 16 h 19 m, 36 d 49'), with an uncertainty
of 3 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 45 degrees.

The GBM light curve shows a typical fast rise and a slow decay
pulse with a duration (T90) of about 10 s (8-1000 keV).
The time-averaged spectrum from T0-2.048 s to T0+15.36 s is
well fit by a power law function. The power law index is -1.59 +/- 0.04

(chi squared 490 for 508 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(4.01 +/- 0.09)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0 in the 8-1000 keV band
is 1.88 +/- 0.04 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090217A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8902
SUBJECT: GRB 090217: Fermi GBM detection
DATE:    09/02/17 16:47:38 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 04:56:42.56 UT on 17 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090217 (trigger 256539404/ 090217206).

The on-ground calculated location, using the GBM trigger 
data, is RA = 211.9, DEC = -2.8  (J2000 degrees, 
equivalent to 14h 08m, -02d 48'), with an uncertainty 
of 1.0 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 34 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve shows one major structured peak with a 
duration (T90) of about 32.8 s (8-1000 keV) and (T50) of 
about 4.6 s (8-1000 keV). 
The time-averaged spectrum from T0+0.003  s to T0+19.584 s is 
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.85 +/- 0.02 and 
the cutoff energy, parameterized as Epeak, is 626 +/- 29 keV 
(chi squared 631.30 for 482 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(3.08 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+6.272 s in the 8-1000 keV band 
is 11.2 +/- 0.3 ph/s/cm^2.

A Band function fits the spectrum equally well (chi squared 629.43 for
481d.o.f.) with Epeak= 610 +/- 32 keV, alpha = -0.845 +/- 0.023 and 
beta = -2.86 +/- 0.36. 

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090217A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8903
SUBJECT: GRB090217: Fermi-LAT Detection
DATE:    09/02/17 17:14:12 GMT
FROM:    Masanori Ohno at ISAS/JAXA  <ohno@astro.isas.jaxa.jp>

Masanori Ohno(ISAS/JAXA), Julie McEnery(NASA/GSFC),
and Veronique Pelassa(CNRS/IN2P3/LPTA) report
on behalf of the Fermi LAT team:

We report a detection by the Fermi Large Area Telescope of emission
from a GRB at 04:56:51 UT with detection significance of more than 5 sigma.
This burst is spatially and temporally correlated with a GBM detected
burst (trigger 256539404, GCN 8902).

This burst was found in a blind search in the LAT data,
and also independently by follow up studies around the GBM location.
The emission continues for up to 20 seconds after the GBM trigger,
 but commences several seconds after the GBM trigger.

The best LAT on-ground localization is found to be (RA,Dec=204.9, -8.4)
with a 90% containment radius of 0.52 deg (statistical; 68%
containment radius: 0.36 deg).

Further analysis is ongoing.

The Fermi LAT point of contact for this burst is
Masanori Ohno
(ohno@astro.isas.jaxa.jp)

The Fermi LAT is a pair conversion telescope designed to cover the
energy band from 20 MeV to greater than 300 GeV. It is the product of an
international collaboration between NASA and DOE in the U.S. and many
scientific institutions across France, Italy, Japan and Sweden.
This message can be cited.


GRB_name: GRB090213A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8904
SUBJECT: GRB 090213: Fermi GBM detection
DATE:    09/02/18 16:50:51 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

Arne Rau (MPE) and Andreas von Kienlin (MPE)
report on behalf of the Fermi GBM Team:

"At 05:39:25.46 UT on 13 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090213 (trigger 256196367 / 090213236).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 327.0, Dec = -53.5 (J2000 degrees, equivalent to 
J2000 21h 48m, -53d 30'), with a statistical uncertainty of 3.7 degrees
(radius, 1-sigma containment, statistical only; there is additionally 
a systematic error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 17 degrees.

Since the source is weak, the time-averaged spectrum is poorly 
constrained."


GRB_name: GRB090217A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8905
SUBJECT: IPN localization of GRB 090217
DATE:    09/02/18 19:55:40 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on
behalf of the GRS-Odyssey GRB team,

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team,

K. Yamaoka, M. Ohno, Y. Fukazawa, T. Takahashi, M. Tashiro, Y. Terada,
T. Murakami, K. Makishima, and Y. Hanabata on behalf of the Suzaku-WAM team,

A. von Kienlin, G. Lichti, and A. Rau, on behalf of the
INTEGRAL SPI-ACS and GRB team, and K. Hurley, on behalf of the INTEGRAL 
SPI-ACS and Odyssey GRB teams, report:

Suzaku-WAM, Konus-Wind, INTEGRAL-SPI-ACS, and Mars Odyssey observed the 
long GRB 090217 at about 04:56:42 UT (corresponding to the Fermi/GBM
trigger 256539404/ 090217206: von Kienlin, GCN 8902; also detected by 
Fermi/LAT: Ohno et al., GCN 8903).

The burst light curve shows a multipeaked structure with a total 
duration of ~40 sec.

Triangulation gives a MO-Konus annulus centered at RA(2000)=132.322 (08h 
49m 17s) Dec(2000)=+18.838 (+18d 50' 18"), whose radius is 76.132 +/- 
0.104 deg (3 sigma), and a Konus-WAM annulus centered at 
RA(2000)=135.708 (09h 02m 50s) Dec(2000)=+21.300 (+21d 17' 59"), whose 
radius is 73.641  0.941 deg (3sigma). These annuli intersect at grazing 
incidence to form two long error boxes, one of which may be eliminated 
by the Konus ecliptic latitude response.
The resulting error box has the coordinates:
-----------------------------------------------------
      RA(2000), deg              Dec(2000), deg
-----------------------------------------------------
Center:
  204.865 (13h 39m 28s)    -7.442 (-07d 26' 31")
Corners:
  212.234 (14h 08m 56s)   +13.782 (+13d 46' 57")
  199.337 (13h 17m 21s)   -19.856 (-19d 51' 21")
  197.625 (13h 10m 30s)   -22.539 (-22d 32' 21")
  210.398 (14h 01m 36s)   + 8.568 (+08d 34' 06")
-----------------------------------------------------

The error box area is 7.2 sq. deg.
This box may be improved.

The box is consistent with the LAT location (Ohno et al., GCN 8903).
The center line of the MO-Konus annulus passes 0.385 degrees from the
center of the Fermi/LAT error circle, and the annulus intersects the
90% containment error circle at:
-----------------------------------------------------
       RA(2000), deg         Dec(2000), deg
-----------------------------------------------------
  204.800 (13h 39m 12s)    -7.890 (-07d 53' 22")
  204.505 (13h 38m 01s)    -8.057 (-08d 03' 24")
  204.471 (13h 37m 53s)    -8.701 (-08d 42' 04")
  204.375 (13h 37m 30s)    -8.379 (-08d 22' 45")
----------------------------------------------------

The K-W light curve of this GRB and IPN triangulation map is
available at http://www.ioffe.ru/LEA/GRBs/GRB090217_T17804/


GRB_name: GRB090217A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8906
SUBJECT: Konus-Wind observation of GRB 090217
DATE:    09/02/18 20:01:46 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The long GRB 090217 (Fermi/GBM trigger 256539404/ 090217206: von 
Kienlin, GCN 8902) localized by Fermi/LAT (Ohno et al., GCN 8903) and 
IPN (Mitrofanov et al., GCN 8905)
triggered Konus-Wind at T0=17804.799 s UT (04:56:44.799) .

As observed by Konus-Wind the burst
had a fluence of 3.13(-0.30, +0.35)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+4.592 s
of 4.72(-0.81, +0.86)x10^-6 erg/cm2/s
(both in the 20 keV - 4 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+24.832 s) is well fitted (in the 20 keV - 4 MeV
range) by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.87(-0.14, +0.15),
and Ep = 534(-78, +105) keV (chi2 = 71.5/73 dof).
Fitting by GRB (Band) model yields:
the low-energy photon index alpha = -0.80(-0.16, +0.18),
the high energy photon index beta < -2.19,
the peak energy Ep = 480(-82, +120) keV (chi2 = 70.0/72 dof).

All the quoted errors are at the 90% confidence level.


GRB_name: GRB090217A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8907
SUBJECT: GRB090217: XRT analysis 
DATE:    09/02/18 21:38:10 GMT
FROM:    Olivier Godet at U.of Leicester  <og19@star.le.ac.uk>

O. Godet (U. Leicester) on behalf the Swift-XRT team

The Swift-XRT started observing the field of GRB090217 (GCN Circ. 8903) 39ks
after the LAT trigger (T0) using an early LAT position (RA,Dec (J2000) =
204.436 deg, -8.858 deg and a 90% confidence error radius of 0.454 deg) which
is 39 arcmin away from that quoted in Ohno et al. (GCN Circ. 8903).

We analysed 7.5ks of Photon Counting (PC) data collected from T0+39ks to
T0+62.8ks. The LAT error circle is larger than the XRT field of view. Three
X-ray sources with a signal-to-noise ratio larger than 3 were found at
(J2000):

S1: RA, Dec, err = 13 37 18.11,  -08 45 28.5, 5.5 arcsec

S2: RA, Dec, err = 13 37 40.35   -09 01 29.7, 4.5 arcsec

S3: RA, Dec, err = 13 37 39.49   -09 02 26.6, 4.4 arcsec

The XRT error radii are quoted at 90% confidence level.

The position S3 is consistent with the AGN HE 1335-0847 previously detected by
ROSAT. The position S2 is consistent with that of a star from the USNO-B1
catalog, while the position S1 is 6.7 arcsec away from a USNO-B1 source.

The data for S1 and S2 are too sparse to check for any variability during the
observation.  Nevertheless, none of these sources are likely to be the X-ray
afterglow of GRB 090217.

This is an official product of the Swift-XRT team.


GRB_name: GRB090217A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8908
SUBJECT: GRB 090217: Suzaku WAM observation of the prompt emission
DATE:    09/02/19 04:55:52 GMT
FROM:    Yoshitaka Hanabata at Hiroshima U  <hanabata@hep01.hepl.hiroshima-u.ac.jp>

Y. Hanabata, Y. Fukazawa, T. Takahashi, T. Uehara, C. Kira (HiroshimaU.),
Y. Terada, M. Tashiro, Y. Urata, A. Endo, K. Onda, N. Kodaka,
K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), M. Ohno,
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), K. Yamaoka,
S. Sugita (Aoyama Gakuin U.), T. Enoto, K. Nakazawa, K. Makishima
(Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori, K. Kono,
H. Hayashi (Univ. of Miyazaki), S. Hong (Nihon U.),
N. Vasquez (Tokyo Tech), on behalf of the Suzaku WAM team, report:

The bright, long Fermi-LAT detected GRB 090217 (Fermi-GBM
trigger #256539404 ; von Kielin et al., GCN 8902;
Fermi-LAT detection ; Ohno et al., ; GCN 8903)
triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers an
energy range of 50 keV - 5 MeV at 04:56:42.98 UT (=T0).
The observed light curve shows a multi-peaked structure
starting at T0-3s, ending at T0+19s with a duration
(T90) of about 14 seconds. The fluence in 100 - 1000 keV
was 1.56(+0.05,-0.09)x10^-5 erg/cm^2.  The 1-s peak flux measured
from T0+7s was 3.0 (+0.2,-0.3) photons/cm^2/s in the same  energy range.
Preliminary result shows that the time-averaged spectrum from
T0-3s to T0+20s is well fitted by a power-law with exponential cutoff model:

 dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
 alpha       0.81(+0.26,-0.31), and
 Epeak       780(+187,-126) keV (chi^2/d.o.f. = 41.0/24).

The GRB Band model also gives a good fit with only
an upper limit on the high-energy photon index as follows:

the low-energy photon index alpha: -0.75(+0.50,-0.28),
the high-energy photon index beta: < -2.33,
and the peak energy Epeak: 748(+195,-175) keV (chi^2/d.o.f = 40.4/23).

Please note that this GRB comes from the WAM 2 on-axis direction, which
has a large uncertaintiy only in absolute flux.
All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst will be available soon at:

http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB090219A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8911
SUBJECT: GRB 090219: Fermi GBM detection
DATE:    09/02/20 17:22:18 GMT
FROM:    Narayana Bhat at U Alabama/Huntsville/GBM  <Narayana.Bhat@nasa.gov>

P. N. Bhat (UA Huntsville)
report on behalf of the Fermi GBM Team:

"At 01:46:18.15 UT on 19th February, 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090219 (trigger 256700780 / 090219074).

The on-ground calculated location, using the GBM trigger
data, is RA = 16.4 d, DEC = +60.2 d (J2000 degrees,
equivalent to 1 h 5.6 m, 60 d 12'), with an uncertainty
of 7 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 137 degrees.

The GBM light curve consists of 2 narrow closely spaced
pulses with a duration (T90) of about 0.5 s (8-1000 keV).
The time-averaged spectrum from T0-0.18 s to T0+0.46 s is
adequately fit by a simple power law function with index -1.43 +/- 0.05
(chi squared 385 for 366 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(8.0 +/- 0.4)E-07 erg/cm^2. The X-sec peak photon flux measured
starting from T0-0.18 s in the 8-1000 keV band
is 7.7 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090222A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8912
SUBJECT: GRB 090222: Fermi GBM detection
DATE:    09/02/22 16:23:16 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 04:17:09.58  UT on 22 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090222 (trigger 256969031 / 090222179).

The on-ground calculated location, using the GBM trigger 
data, is RA = 120.2, DEC = +43.4 (J2000 degrees, 
equivalent to 08h 01m, +43d 24'), with an uncertainty 
of 5.5 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 80 degrees.

The GBM light curve shows one main peak with substructure 
with a duration (T90) of about 18 s (8-1000 keV). 
The time-averaged spectrum from T0-2.688 s to T0+14.720 s is 
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.00 +/- 0.11 
and the cutoff energy, parameterized as Epeak, is 157.7 +/- 19.8 keV
(chi squared 523.89 for 480 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(2.19 +/- 0.19)E-06 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+6.528 s in the 8-1000 keV band 
is 1.10 +/- 0.14 ph/s/cm^2.

A Band function fits the spectrum equally well 
(chi squared 522.58 for 479 d.o.f.) with 
Epeak= 147.9 +/- 27.1  keV, alpha = -0.97 +/- 0.14 
and beta = -2.56 +/- 0.66. 

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB081211B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8914
SUBJECT: GRB 081211B: Nearby cluster
DATE:    09/02/23 05:25:22 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom, and N. R. Butler (UC Berkeley) report:

GRB 081211B was discovered in the Swift-BAT slew survey (Copete et al, 
GCN 8661) and, based on observations by Konus-Wind (Golenetskii et al., 
GCN 8676), was classified as a possible short burst with an extended 
emission component.  We note that the GRB localization lies within a 
visual galaxy overdensity in SDSS archival imaging, and near the centers 
of several reported clusters in the literature, which likely correspond 
to the same physically extended structure: ZW 3893, Abell 1196, and 
MaxBCG J168.22310+53.83028.

Redshifts from the Sloan Digital Sky Survey of the brightest two 
apparent cluster members place this cluster at a probable redshift of 
z=0.216.

On the night of 2009-02-19 (UT) we observed the field with Keck I (+ 
LRIS) for an exposure time of 990 sec (g-band) and 870 sec (R-band) 
simultaneously through thin cloud cover.  No host galaxy underlying the 
XRT position (Page et al., GCN 8666) is detected to approximately R > 
25, g > 26 mag.  The nearest catalogued objects are:

SDSS J111303.09+534953.8  g=21.26 r=20.26 i=20.03 (7" = 24 kpc)
SDSS J111304.73+534959.5  g=20.56 r=19.25 i=18.84 (16" = 56 kpc)

An additional very faint extended object is located 3" west of the 
center of the XRT position, outside the 90% confidence error circle. 
Images of the field (from our observations and from SDSS) are posted to:

http://lyra.berkeley.edu/~dperley/081211b/081211b_keck.png 
http://lyra.berkeley.edu/~dperley/081211b/081211b_sdss.png

If the BAT detection represents extended emission from this event and no 
fainter host galaxy is found, this would constitute an additional case 
of a short GRB event with detected extended emission occurring without a 
coincident host galaxy (after GRB 080503 - arXiv:0811.1044), as well as 
an additional example of a short burst occurring within a galaxy cluster 
(see also e.g. GRBs 050509B, 050813, 051210, 061201).  The isotropic 
gamma-ray energy release at the cluster redshift would be 7 x 10^49 erg 
in the BAT bandpass, comparable to values measured for other short GRBs.

We encourage deeper observations of the field.


GRB_name: GRB090206A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8916
SUBJECT: GRB 090206: Fermi GBM detection
DATE:    09/02/27 16:00:52 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi (MPE) and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team:


"At 14:52:42.17 UT on 06 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090206 (trigger 255624764 / 090206620).
The on-ground calculated location, using the GBM trigger
data, is RA = 157.2, DEC = +14.5 (J2000 degrees,
equivalent to 10h 29m, 14d 30'), with an uncertainty
of 8.7 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 72 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of a single peak
with a duration (T90) of about 0.8 s (8-1000 keV).
The time-averaged spectrum from T0-0.064 s to T0+0.512 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.65 +/- 0.14 and
the cutoff energy, parameterized as Epeak, is 710 +/- 170 keV
(chi squared 402 for 456 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.04 +/- 0.06)E-06 erg/cm^2. The 64-msec peak photon flux
measured starting from T0 in the 8-1000 keV band is
19.0 +/- 1.0 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090227A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8917
SUBJECT: GRB 090227: Fermi GBM detection
DATE:    09/02/27 19:20:13 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E. Bissaldi (MPE) reports on behalf of the Fermi GBM Team: 


"At 07:25:57.00 UT on 27 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090227 (trigger 257412359 / 090227310).
The on-ground calculated location, using the GBM trigger
data, is RA = 3.2, DEC = -43.1 (J2000 degrees,
equivalent to 00h 13m, -43d 06'), with an uncertainty
of 1.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 21 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve shows one main FRED-like pulse with substructure.
Emission continues to at least 80 seconds.
T90 (8-1000 keV) is about 50 s and T50 (8-1000 keV) is about 20 s.
The time-averaged spectrum from T0 to T0+16.3 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.91 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 1355 +/- 259 keV
(chi squared 748 for 729 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(9.0 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.9 s in the 8-1000 keV band
is 4.57 +/- 0.13 ph/s/cm^2.

A Band function fits the spectrum equally well (chi squared 
748 for 728 d.o.f.) with Epeak = 1357 +/- 284 keV, 
alpha = -0.92 +/- 0.06 and beta = -3.6 +/- 2.9.


The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090228A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8918
SUBJECT: GRB 090228: Fermi GBM detection
DATE:    09/02/28 17:42:15 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 04:53:20.91 UT on 28 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located the bright short GRB 090228 (trigger 257489602 /
090228204).
The on-ground calculated location, using the GBM trigger 
data, is RA = 106.8, DEC = -24.3 (J2000 degrees, equivalent 
to 07h 07m, -24d 18'), with a statistical uncertainty of 
less than 1 degree (radius, 1-sigma containment) and an additional 
systematic error which is currently estimated to be 2 to 3 degrees.

The angle from the Fermi LAT boresight is 16 degrees

This short GRB shows a single bright pulse followed 
by a peak of significantly lesser intensity. 
The burst duration (T90) is about 0.8 s (8-1000 keV).
The time-averaged spectrum from T0-0.016 s to T0+0.176 s is 
best fit by a Band function with Epeak = 849 +/- 44 keV, 
alpha = -0.35 +/- 0.04, and beta = -2.98 +/- 0.25
(chi squared 732.29 for 723 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(6.1 +/- 0.09)E-06 erg/cm^2. The 0.32-sec peak photon flux measured 
starting from T0 s in the 8-1000 keV band is 133 +/- 8 ph/s/cm^2.

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090301A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8920
SUBJECT: GRB 090301: Swift detection of a burst
DATE:    09/03/01 07:07:31 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

L. Vetere (PSU), C. Gronwall (PSU), J. A. Kennea (PSU),
C. B. Markwardt (CRESST/GSFC/UMD), D. M. Palmer (LANL),
T. Sakamoto (NASA/UMBC), M. H. Siegel (PSU) and M. C. Stroh (PSU)
report on behalf of the Swift Team:

At 06:55:55 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090301 (trigger=344582).  Swift could not slew to the burst
due to its proximity to the Sun (34 degrees).  The BAT on-board 
calculated location is 
RA, Dec 338.140, +26.642 which is 
   RA(J2000) = 22h 32m 34s
   Dec(J2000) = +26d 38' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex multiple-peak
structure with a duration of about 50 sec.  The peak count rate
was ~20,0000 counts/sec (15-350 keV), at ~23 sec after the trigger. 

Due to an observing constraint, Swift cannot slew to the BAT position. 
There will thus be no XRT or UVOT data for this trigger. The source 
will become observable again after April 15th. 

Burst Advocate for this burst is L. Vetere (vetere AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090227B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8921
SUBJECT: GRB 090227B: Fermi GBM detection
DATE:    09/03/01 08:49:18 GMT
FROM:    Sylvain Guiriec at UAH  <sylvain.guiriec@lpta.in2p3.fr>

S. Guiriec (UAH)
reports on behalf of the Fermi GBM Team:

"At 18:31:01.41 UT on 27 February 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located the short and bright GRB 090227B
(trigger 257452263 / 090227772).

The on-ground calculated location, using the GBM trigger data, is
RA = 11.81, Dec = +32.17 (J2000 degrees, equivalent to 11h48m36,+32d10'12),
with an uncertainty of 1.77 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 72 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of one spike with a duration (T90) of about
0.9 s (10-1000 keV).
The time-averaged spectrum from T0-0.1s to T0+0.4s is best fitted by a Band
function with Epeak = 2255 +/- 116 keV,  alpha = -0.53 +/- 0.02, and
beta = -3.04 +/- 0.23 (chi squared 673 for 607 d.o.f.).

The event fluence (10-1000 keV) in this time interval is
(0.87 +/- 0.01)E-05 erg/cm^2. The 1-sec peak photon flux measured starting
from T0 in the 10-1000 keV band is 34.6 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090301B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8922
SUBJECT: GRB 090301B: Fermi GBM detection
DATE:    09/03/01 16:38:46 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 07:33:37.98 UT on 01 March 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090301B (trigger 257585619 / 090301315 ).
The on-ground calculated location, using the GBM trigger 
data, is RA = 350.3, DEC = 9.0 (J2000 degrees, 
equivalent to 23h 21m, 09d 00'), with an uncertainty 
of 4.2 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 56 degrees.

The GBM light curve shows a single peak lasting about 5 s 
superimposed on a lower-level continuum.
The burst duration (T90) is about 28 s (8-1000 keV)
The time-averaged spectrum from T0-1.536 s to T0+3.584 s is 
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.03 +/- 0.09 and
the cutoff energy, parameterized as Epeak, is 546 +/- 133 keV
(chi squared 703.17 for 731 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(2.69 +/- 0.13)E-06 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+1.536 s in the 8-1000 keV band 
is 4.4 +/- 0.1 ph/s/cm^2.

A Band function fits the spectrum equally well 
(chi squared 700.28 for 730 d.o.f.) with Epeak= 427 +/- 147 keV, 
alpha = -0.98 +/- 0.12 and beta = -1.93 +/- 0.24. 

The spectral analysis results presented above are preliminary; 
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090301A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8923
SUBJECT: GRB 090301A: Swift-BAT refined analysis
DATE:    09/03/01 17:22:50 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

E. E. Fenimore (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), A. M. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU), L. Vetere (PSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-61 to T+242 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 090301A (trigger #344582)
(Vetere, et al., GCN Circ. 8920).  The BAT ground-calculated position is
RA, Dec = 338.142, 26.639 deg, which is 
   RA(J2000)  =  22h 32m 34.2s 
   Dec(J2000) = +26d 38' 19.0" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 35%.
 
The mask-weighted light curve shows a complex of overlapping and separated
peaks starting at ~T-20 sec and ending some time after T+86 sec
at which time the burst location went ouf out the BAT FOV when Swift slewed
to the next planned target.  Given that the burst location will not come out
of the Sun observing consrtaint until after April 15,  we will not have 
any further data on this burst.  T90 (15-350 keV) is 41.0 +- 2.2 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-17.0 to T+72.2 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.08 +- 0.12, 
and Epeak of 343.3 +- 328.8 keV (chi squared 37.39 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.3 +- 0.03 x 10^-5 erg/cm2
and the 1-sec peak flux measured from T+23.07 sec in the 15-150 keV band is
18.7 +- 0.6 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.25 +- 0.03 (chi squared 43.70 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level.
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/344582/BA/


GRB_name: GRB090301A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8924
SUBJECT: Konus-Wind observation of GRB 090301A
DATE:    09/03/02 14:56:38 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The bright long GRB 090301A (Swift-BAT trigger #344582: Vetere et al., 
GCN 8920; Fenimore et al., GCN 8923) triggered Konus-Wind at 
T0=24949.694 s UT (06:55:49.694).

The burst light curve shows a multipeaked structure with a duration of
~50 s, followed by a weak tail marginally seen up to ~T0+200 s.

As observed by Konus-Wind the burst
had a fluence of (1.13 +/- 0.08)x10^-4 erg/cm2,
and a 64-ms peak flux measured from T0+25.408 s
of (1.51 +/- 0.23)x10^-5 erg/cm2/s
(both in the 20 keV - 5 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+44.032 s) is well fitted (in the 20 keV - 5 MeV
range) by GRB (Band) model for which:
the low-energy photon index alpha = -0.87 +/- 0.05,
the high energy photon index beta = -2.65(-0.47, +0.25),
the peak energy Ep = 429(-32, +34) keV (chi2 = 77.5/76 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB090301_T24949/


GRB_name: GRB090227B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8925
SUBJECT: IPN localization of short bright GRB 090227B
DATE:    09/03/03 15:28:38 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team,

K. Yamaoka, M. Ohno, Y. Fukazawa, T. Takahashi, M. Tashiro, Y. Terada,
T. Murakami, K. Makishima, and Y. Hanabata on behalf of the Suzaku-WAM team,

V. Connaughton, and M. Briggs on behalf of the Fermi GBM team,

A. von Kienlin, G. Lichti, and A. Rau, and K. Hurley on behalf of the
INTEGRAL SPI-ACS team report:

Konus-Wind, INTEGRAL-SPI-ACS, and Suzaku-WAM observed the bright short
hard GRB 090227B at about 18:31:00 UT (corresponding to the Fermi/GBM
trigger 257452263 / 090227772: Guiriec, GCN 8921).

The burst light curve shows a single pulse with a duration of ~0.2 sec.

Triangulation gives a Konus-WAM annulus centered at RA(2000)=336.619
(22h 26m 29s) Dec(2000)=-16.013 (-16d 00' 46"), whose radius is 56.968
0.097 deg (3 sigma), and a Konus-SPI-ACS annulus centered at
RA(2000)=337.423 (22h 29m 42s) Dec(2000)= -19.538 (-19d 32' 16"), whose
radius is  59.273  0.224 deg (3sigma). These annuli intersect at
grazing incidence to form two long error boxes, one of which may be
eliminated by the GBM location (Guiriec, GCN 8921).
The resulting error box has the coordinates:
-----------------------------------------------------
       RA(2000), deg              Dec(2000), deg
-----------------------------------------------------
Center:
    13.499 (00h 54m 00s)   +28.401 (+28d 24' 05")
Corners:
    8.168 (00h 32m 40s)   +32.167 (+32d 10' 02")
   11.644 (00h 46m 34s)   +30.005 (+30d 00' 20")
   17.745 (01h 10m 59s)   +24.579 (+24d 34' 44")
   15.181 (01h 00m 43s)   +26.796 (+26d 47' 46")
-----------------------------------------------------

The error box area is 1.531 sq. deg.

This error box may be improved.

We have also derived a Konus-GBM annulus for the burst which is fully 
consistent with the Konus-WAM annulus.

The GBM location is consistent with the IPN box.
The center of the GBM location lies 1.830 deg from the Konus-WAM annulus
and 4.041 deg from the center of the box.
You can find the GBM confidence contours overplotted on the IPN box at 
the IPN triangulation map. The contours should be considered as 
preliminary and we expect the GBM localization code will be
refined. No systematic error has been added.

The Konus-Wind light curve of this GRB and IPN triangulation map is
available at http://www.ioffe.ru/LEA/GRBs/GRB090227_T66659/


GRB_name: GRB090227B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8926
SUBJECT: Konus-Wind observation of bright short GRB 090227B
DATE:    09/03/03 16:01:32 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team, report:

The bright short hard GRB 090227B (Fermi/GBM trigger 257452263 /
090227772: Guiriec, GCN 8921) localized by IPN (Golenetskii et al., GCN
8925) triggered Konus-Wind at T0=66659.079 s UT (18:30:59.079).

As observed by Konus-Wind the burst
had a fluence of (2.75 +/- 0.27)x10^-5 erg/cm2,
and a 16-ms peak flux measured from T0+0.008 s
of 3.98(-0.58, +0.59)x10^-4 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+0.192 s) is well fitted (in the 20 keV - 10 MeV
range) by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.43(-0.09, +0.10),
and Ep = 2253(-262, +292) keV (chi2 = 29.4/47 dof).
Fitting by GRB (Band) model yields:
the low-energy photon index alpha = -0.41(-0.10, +0.12),
the high energy photon index beta < -2.5,
the peak energy Ep = 2134(-326, +332) keV (chi2 = 28.1/46 dof).

The emission is clearly seen up to 10 MeV.

All the quoted errors are at the 90% confidence level.


GRB_name: GRB090228B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8927
SUBJECT: GRB 090228B: Fermi GBM detection
DATE:    09/03/03 23:31:08 GMT
FROM:    Vandiver Chaplin at UAH/Fermi-GBM  <chapliv@email.uah.edu>

V.Chaplin (UAH) reports on behalf of the Fermi GBM Team:

"At 23:25:01.02 UT on 28 FEB 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090228B (trigger 257556303 / 090228976).

The on-ground calculated location, using the GBM trigger
data, is RA = 356.5, DEC = +36.1 (J2000 degrees,
equivalent to 23h 44m, +36d 10' ), with an uncertainty
of 1.77 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 20 degrees.

The GBM light curve consists of one main pulse
with a duration (T90) of about 7.232 s (8-1000 keV).
The time-averaged spectrum from T0-1.408 s to T0+5.760 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.6963 +/- 0.293 and
the cutoff energy, parameterized as Epeak, is 147.8 +/- 34.1 keV
(chi squared 221.01 for 235 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(9.9607 +/- 0.22)E-07 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.688 s in the 8-1000 keV band
is 2.53 +/- 1.0 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090227A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8928
SUBJECT: Konus-RF catches first GRB and SGR bursts
DATE:    09/03/04 15:01:46 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, V. 
Il'inskii, P. Oleynik, M. Ulanov, D. Svinkin, on behalf of the Konus-RF 
and Konus-Wind teams, report:

At 07:25:57 UT on February 27, 2009 the KONUS-RF gamma-ray spectrometer 
detected its first gamma-ray burst, GRB 090227A (Fermi/GBM trigger 
257412359 / 090227310: Bissaldi GCN 8917).
That day at 13:43:36 UT the instrument detected a bright short soft 
burst from the AXP/SGR 1E1547.0-5408.
Both bursts also triggered Konus-Wind.

The Konus-RF gamma-ray spectrometer is an instrument of the 
CORONAS-PHOTON solar space observatory that was launched on January 30, 
2009 into a low-Earth low-eccentricity, high-inclination orbit (altitude 
547-592 km, inclination 82.5 deg). CORONAS-PHOTON is a 3-axis 
stabilized, Sun-pointing spacecraft. Konus-RF has been successfully 
operating since February 19.

The Konus-RF experiment is aimed at studying of temporal and spectral 
characteristics of solar flares, gamma-ray bursts, and SGR bursts in a 
wide energy range from 10 keV to 10 MeV. It consists of two identical 
omnidirectional detectors one of which points toward the Sun thereby 
observing the solar hemisphere, and the other observes the antisolar 
hemisphere. Thus, the instrument provides continuous monitoring of the 
unocculted sky. However, the usable exposure time is severely limited by 
passage through the radiation belts at high latitudes and the South 
Atlantic Anomaly. Each detector employs NaI(Tl) crystal, 127 mm in 
diameter and 76.2 mm in height, supplied with a beryllium entrance 
window. The Konus-RF instrument is an advanced modification of the 
Russian-American Konus-Wind spectrometer. More details can be found at 
http://www.astro.mephi.ru/coronos-photon_conusrf_e.htm

The Konus-RF and Konus-Wind light curves of the SGR burst 090227 are 
available at http://www.ioffe.ru/LEA/SGRs/090227_T49414/


GRB_name: GRB090301A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8929
SUBJECT: GRB 090301A: Suzaku WAM observation of the prompt emission
DATE:    09/03/04 15:39:51 GMT
FROM:    Kazutaka Yamaoka at Aoyama Gakuin U  <yamaoka@phys.aoyama.ac.jp>

T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo),
Y. Hanabata, Y. Fukazawa, T. Takahashi, T. Uehara, C. Kira (Hiroshima U.),
Y. Terada, M. Tashiro, Y. Urata, A. Endo, K. Onda, N. Kodaka,
K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), M. Ohno,
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), K. Yamaoka,
S. Sugita (Aoyama Gakuin U.), Y.E. Nakagawa, T. Tamagawa (RIKEN),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori, K. Kono,
H. Hayashi (Univ. of Miyazaki), S. Hong (Nihon U.),
N. Vasquez (Tokyo Tech), on behalf of the Suzaku WAM team, report:

The bright long GRB 090301A (Swift/BAT trigger #344582; Fenimore et al., GCN 8923) 
triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers 
an energy range of 50 keV - 5 MeV at 06:55:50.862 UT (=T0).

The observed light curve shows a multi-peaked structure lasting from T0-2s 
to T0+48s with a duration (T90) of about 35 seconds. The fluence in 100 - 
1000 keV was 6.9(-0.5, +0.1) x 10^-5 erg/cm^2.  The 1-s peak flux measured 
from T0+27 was 14.8(+/-0.9) photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from 
T0-2s to T0+48s is fitted by a GRB Band model as follows.
the low-energy photon index alpha: -0.93 (-0.16, +0.18),
the high-energy photon index beta: -2.82 (-0.74, +0.29),
the break energy E0:       536 (-101, +131) keV,
and the peak energy Epeak: 574 +/- 170 keV (chi^2/d.o.f = 68/56).

Due to the high counting rate of this GRB, a 1% systematic error 
 was added for low energy channels. 
All the quoted errors are at the 90% confidence level.  

The light curves for this burst are available at:
 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB090304A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8930
SUBJECT: GRB 090304: Fermi GBM detection
DATE:    09/03/04 16:14:43 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

Arne Rau (MPE) reports on behalf of the Fermi GBM Team:

"At 05:10:48.16 UT on 04 March 2009, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 090304 (trigger 257836250 / 090304.216).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 246.4, Dec = -80.9 (J2000 degrees, equivalent to
J2000 16h 25m, -80d 54'), with a statistical uncertainty of 13.1 degrees
(radius, 1-sigma containment, statistical only; there is additionally
a systematic error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 31 degrees.

Since the source is weak, the time-averaged spectrum is poorly constrained.

This event has also been detected by INTEGRAL SPI-ACS."


GRB_name: GRB090303A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8931
SUBJECT: GRB 090303: Fermi GBM detection
DATE:    09/03/04 17:23:12 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

Arne Rau (MPE) reports on behalf of the Fermi GBM Team:

"At 13:00:37.04 UT on 03 March 2009, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located a weak source (trigger 257778039 / 090303.542).

The human-in-the-loop location is RA=223.7, Dec=-68.2 (J2000 degrees)
with an uncertainty of 12.1 degrees(radius, 1-sigma containment, 
statistical
only; there is additionally a systematic error which is currently 
estimated to
be 2 to 3 degrees).

The most likely nature of the source is a GRB, but it could also be an SGR.
Since the source is very weak, it is not possible to find a more reliable
on-ground calculated location and to perform any spectral analysis."


GRB_name: GRB090305A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8932
SUBJECT: GRB 090305: Swift detection of a short burst
DATE:    09/03/05 05:38:42 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

A. P. Beardmore (U Leicester), J. R. Cummings (NASA/UMBC),
S. T. Holland (CRESST/USRA/GSFC), C. B. Markwardt (CRESST/GSFC/UMD),
C. Pagani (PSU), K. L. Page (U Leicester) and D. M. Palmer (LANL)
report on behalf of the Swift Team:

At 05:19:51 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090305 (trigger=345127).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is RA, Dec 241.756, -31.567 which is 
   RA(J2000) = 16h 07m 02s
   Dec(J2000) = -31d 34' 00"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single short spike
with a duration of about 0.4 sec.  The peak count rate
was ~2500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 05:21:23.8 UT, 92.7 seconds after
the BAT trigger. No source was detected in the promptly available XRT
data in an exposure time of 92.8 seconds before Swift slewed away. We are 
waiting for the full dataset to detect and localise the
XRT counterpart. 


UVOT took a finding chart exposure of 102 seconds with the White filter
starting 96 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. Because part of the 2.7'x2.7'
sub-image was not received, the overlap with the BAT error circle is uncertain. 
The overlap is at most 25%. The coverage of the BAT error circle by the 8'x8'
region for the list of sources generated on-board is uncertain because the
large number of sources filled the available telemetry. No correction has been
made for the expected extinction corresponding to E(B-V) of 0.22. 




We note the presence of a ROSAT survey source, 1RXS J160703.2-313251,
within the BAT error circle.  Further data are required to determine
whether this object is related to the burst. 

Burst Advocate for this burst is A. P. Beardmore (apb AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090305A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8933
SUBJECT: GRB090305: GMOS-S Candidate Optical Afterglow
DATE:    09/03/05 10:32:47 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, B. E. Cobb, D. A. Perley, and J. S. Bloom (UC Berkeley)
report on behalf of a larger collaboration:

We have imaged the field of the short GRB 090305 (Beardmore et al., GCN
8932) with GMOS mounted on the Gemini South telescope beginning
approximately 27 minutes after the burst.  Observations were taken in
the Sloan g', r', and i' filters and cover nearly the entire BAT error
circle.

Inside the BAT error circle, we find a fading point source at the location
(J2000):

   RA: 16:07:07.61
   Dec: -31:33:21.9

Calibrating with respect to the USNO-B1 object at 16:07:06.58, -31:33:37.9
(R2=18.99), we measure an initial magnitude of R ~ 23.3.  The source fades
by approximately 1.1 mag over the next two hours, corresponding to a
power-law decay index of ~ 0.6 (assuming no contribution from an
underlying host galaxy).  At this point we tentatively consider this
source the afterglow of GRB090305, although we await confirmation from the
XRT.

We wish to thank the staff at Gemini South, in particular Peter Pessev,
for performing our target of opportunity observations.


GRB_name: GRB090305A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8934
SUBJECT: GRB 090305: Magellan confirmation of the optical afterglow
DATE:    09/03/05 12:40:28 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) and D. Kelson (OCIW) report:

"We imaged the BAT error circle of the short GRB 090305 (GCN 8932) with
IMACS on the Magellan/Baade 6.5-m telescope.  Observations were taken in R
band on 2009 March 5 at 06:48 and 09:11 UT (88 and 231 min after the
burst, respectively).  We confirm the existence of the fading source
reported by Cenko et al. from Gemini South observations (GCN 8933) and
consider this source to be the afterglow of GRB 090305."


GRB_name: GRB090227A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8935
SUBJECT: GRB 090227A: Suzaku WAM observation of the prompt emission
DATE:    09/03/05 14:12:32 GMT
FROM:    Yoshitaka Hanabata at Hiroshima U  <hanabata@hep01.hepl.hiroshima-u.ac.jp>

Y. Hanabata, Y. Fukazawa, T. Takahashi, T. Uehara, C. Kira (Hiroshima U.),
Y. Terada, M. Tashiro, Y. Urata, A. Endo, K. Onda, N. Kodaka,
K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), M. Ohno,
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), K. Yamaoka,
S. Sugita (Aoyama Gakuin U.), T. Enoto, K. Nakazawa, K. Makishima 
(Univ. of Tokyo), Y. E. Nakagawa, T. Tamagawa (RIKEN),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori, K. Kono,
H. Hayashi (Univ. of Miyazaki), S. Hong (Nihon U.),
N. Vasquez (Tokyo Tech), on behalf of the Suzaku WAM team, report:

The long GRB 090227A (Bissaldi et al., GCN 8917) triggered the
Suzaku Wide-band All-sky Monitor (WAM) which covers an energy
range of 50 keV - 5 MeV at 07:25:56.862 UT (=T0).

The observed light curve shows a multi-peaked structure starting at T0-1s,
ending at T0+17s with a duration (T90) of about 12.7 seconds. The
fluence in 100 - 1000 keV was 8.00(-1.41, +0.36) x 10^-6 erg/cm^2. The
1-s peak flux measured from T0+1s was 2.27(-1.00, +0.14)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0-1s
to T0+17s is fitted by a power-law with exponential cutoff model:

 dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
 alpha       1.16(-0.28, +0.22), and
 Epeak       1328(-465, +951) keV (chi^2/d.o.f. = 6.73/14).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB090305A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8936
SUBJECT: GRB 090305, Swift-BAT refined analysis
DATE:    09/03/05 18:15:07 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

H. A. Krimm (GSFC/USRA),  S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL),
N. Gehrels (GSFC), C. B. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-61 to T+242 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 090305 (trigger #345127)
(Beardmore et al., GCN 8932).  The BAT ground-calculated position is
RA, Dec = 241.764, -31.572 deg which is
  RA(J2000)  =  16h 07m 03.5s
  Dec(J2000) = -31d 34' 20.9"
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
This position is 1.3 arcmin from the optical afterglow reported by
Cenko et al. (GCN Circ 8933). The partial coding was 50%.

The lightcurve consists of two pulses, the first about 0.08 seconds
long and the second about  0.28 seconds long.  T90 (15-350 keV) is
0.4 +- 0.1 sec (estimated error including systematics).  There was
very little emission seen in the BAT low energy band, 15-25 keV.

The time-averaged spectrum from T+0.0 to T+0.4 sec is best fit by a
simple power-law model.  The power law index of the time-averaged
spectrum is 0.86 +- 0.33.  The fluence in the 15-150 keV band is
7.5 +- 1.3 x 10^-08 erg/cm2.  The 1-sec peak photon flux measured from
T-0.29 sec in the 15-150 keV band is 1.9 +- 0.4 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/345127/BA/


GRB_name: GRB090305A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8937
SUBJECT: GRB 090305: Swift-XRT refined analysis
DATE:    09/03/06 01:17:55 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A.P. Beardmore, K. L. Page, P.A. Evans (U. Leicester), C. Pagani, J. Kennea,
D.N. Burrows (PSU) report on behalf of the Swift-XRT team :

The Swift-XRT began observing the field of the short GRB 090305
(Beardmore et al. GCN Circ. 8932) in photon counting mode at
2009-03-05T05:21:37, 103.4 s after the trigger.  The first orbit of
data lasted only 90 s before the spacecraft slewed to another target
because of an observing constraint.

The default data processing does not reveal any X-ray source during
the first orbit (103.4 to 193.5 s post trigger), either within the BAT
refined error circle (Krimm et al. GCN Circ. 8936) or at the location
of the optical afterglow (Cenko et al. GCN Circ. 8933) - the latter
occurring close to a bad-column on the XRT CCD.  However, by relaxing
the default screening criteria we find 8 counts in a 10 pixel radius
circle extraction region at the location of the optical afterglow,
compared with a predicted background level of 1.0 count (where an
annulus with radii 15 to 100 pixels was used to sample the local
background level), implying a greater than 99.99 percent confidence
detection (Kraft, Burrows, and Nousek 1991, Ap. J., 374, 344). The
clustering of the counts, their proximity to the location of the
optical afterglow and their detection significance allow us to
conclude the afterglow was detected by the XRT at this time. The
estimated count rate is 0.112 +0.051 -0.041 count/s (where a
systematic error of 5 percent has been included in the 1 sigma error
estimate to account for the PSF correction uncertainty).  Applying a
canonical GRB count to observed flux conversion factor of 5e-11 erg
cm^-2 count^-1 (for a photon index of 1.98, Evans et al. 2009, MNRAS,
submitted. arXiv:0812.3662, http://www.swift.ac.uk/xrt_spectra), we
estimate the observed 0.3-10 keV flux was (5.5 +2.6 -2.0)e-12 
erg cm^-2 s^-1.

A further 2.05 ks of data was taken in orbit two, from 3.92 to 5.97 ks
after the trigger, where the optical afterglow position was located
away from the XRT CCD bad column. This showed the source was no longer
detected and a 3 sigma upper limit to the count rate of 7.0e-3 count/s
was obtained.  Using all of the available data after the first orbit
(i.e. presently an exposure of 12.64 ks from 3.92 to 46.1 ks post
trigger) reduces the 3 sigma upper limit to 1.7e-3 count/s.  The X-ray
data suggest the source faded with a decay slope of at least ~0.8.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090305A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8938
SUBJECT: GRB 090305: Swift/UVOT Upper Limits
DATE:    09/03/06 12:49:24 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) and A. P. Beardmore (U Leicester)
report on the behalf of the Swift UVOT team:

     The Swift/UVOT observed the field of GRB 090305 starting 78 s
after the BAT trigger (Beardmore, et al. 2009, GCN Circ. 8932).
Settled exposures started at T+96 s.  We do not find any new source,
relative to the DSS, USNO-B1.0, or 2MASS, or any variable source at
the position of the GMOS-S afterglow (Cenko, et al. 2009, GCN
Circ. 8933).  Preliminary 3-sigma upper limits for detecting a source
in the white finding chart, and the co-added images, using a 2.5
arcsecond radius circular aperture, are

Filter   T_start   T_stop   Exp(s)     Mag
------------------------------------------
white        96      198      100   >20.6

v        3503   11,765     1034   >20.6
b        4323   15,980     1278   >21.8
u        4118     5755      393   >20.6
uvw1       3913     5550      393   >20.6
uvm2       3708     5345      393   >20.3
uvw2       4734   17,549     1723   >21.6
white      4528   16,892     1982   >22.7
------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight corresponding to a
reddening of E_{B-V} = 0.21 mag (Schlegel, et al., 1998, ApJS, 500,
525).  All photometry is on the UVOT photometry system described in
Poole et al. (2008, MNRAS, 383, 627).

    The GMOS-S afterglow is located in the wings of the B = 13.72
mag USNO-B1.0 star 0584-0391760.  UVOT photometry at this location is
contaminated by this star.
Please update my e-mail address in your Address Book to <Stephen.T.Holland@nasa.gov 
 >.
/
\
/


GRB_name: GRB090306A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8939
SUBJECT: GRB 090306: Swift detection of a possible burst
DATE:    09/03/06 15:21:00 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

O. Godet (U Leicester), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
S. Campana (INAF-OAB), P. A. Evans (U Leicester), J. A. Kennea (PSU),
R. Margutti (Univ Bicocca&OAB), J. P. Osborne (U Leicester),
C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL),
M. Perri (ASDC), P. Romano (INAF-IASFPA),
B. A. Rowlinson (U Leicester), G. Stratta (ASDC), M. C. Stroh (PSU),
G. Tagliaferri (INAF-OAB) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 13:54:24 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090306 (trigger=345396).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 16.740, -50.065 which is 
   RA(J2000) = 01h 06m 58s
   Dec(J2000) = -50d 03' 54"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a short, 
hard structure with a duration less than a single 64 msec timebin. 
The peak count rate was ~2000 counts/sec (15-350 keV), at ~0 sec
after the trigger. 

The XRT began observing the field at 13:55:57.4 UT, 95.5 seconds
after the BAT trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 16.74294, -50.00206 which
is equivalent to:
   RA(J2000)  = 01h 06m 58.31s
   Dec(J2000) = -50d 00' 07.4"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
position may be improved as more data are received; the latest position
is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.37e+20 cm^-2 (Kalberla et al. 2005). 

At this time we do not have UVOT data. 

This trigger was the first of a new triggering function
within BAT (the so called Subthreshold trigger).  While there
is a real source in the XRT initial image, this would say
the trigger is a real GRB.  However because we did not receive
the usual BAT Position message (for reasons yet unknown),
we caution that we can not say with confidence that this is a
real burst.  We will not have the full data downlinked
until ~17:00 UT. 

Burst Advocate for this burst is O. Godet (og19 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090305C
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8941
SUBJECT: IPN localization of short GRB 090305C
DATE:    09/03/06 18:09:18 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind 
and Konus-RF teams,

K. Yamaoka, M. Ohno, Y. Hanabata, Y. Fukazawa, T. Takahashi, M. Tashiro,
  Y. Terada, T. Murakami, and K. Makishima on behalf of the Suzaku-WAM team,

J. Cummings, S. Barthelmy, N. Gehrels, and H. Krimm, on behalf of
the Swift-BAT team,

A. von Kienlin, G. Lichti, and A. Rau, and K. Hurley on behalf of the
INTEGRAL SPI-ACS team report:

Suzaku-WAM, Konus-Wind, Konus-RF, Swift-BAT, and INTEGRAL-SPI-ACS 
observed the short GRB 090305C at about 62379 s UT (17:19:39). The burst 
was outside the coded field of view of the BAT.

The burst light curve shows a multipeaked structure with a duration of 
~1 sec.

We have triangulated it to the following 3-sigma
error box:
-----------------------------------------------
       RA(2000), deg            Dec(2000), deg
-----------------------------------------------
Center:
   34.187 (02h 16m 45s)   -22.840 (-22d 50' 23")
Corners:
   34.482 (02h 17m 56s)   -17.203 (-17d 12' 09")
   34.645 (02h 18m 35s)   -19.974 (-19d 58' 28")
   33.140 (02h 12m 34s)   -28.787 (-28d 47' 14")
   33.533 (02h 14m 08s)   -25.759 (-25d 45' 32")
-----------------------------------------------

The error box area is 2.524 sq. deg.

This error box may be improved.

The Konus-Wind light curve of this GRB and the IPN triangulation map is
available at http://www.ioffe.ru/LEA/GRBs/GRB090305_T62376/


GRB_name: GRB090306B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8944
SUBJECT: GRB 090306B: Burst detection from Swift-BAT slew data
DATE:    09/03/07 16:50:40 GMT
FROM:    Antonio Copete at Harvard U  <acopete@head.cfa.harvard.edu>

A. Copete, J. Grindlay (Harvard)
S. Barthelmy, C. Markwardt, N. Gehrels (NASA/GSFC)

We report the detection of a bright GRB by the BAT Slew Survey (BATSS)  
in the slew that started at 23:07:02 and lasted 66 sec. The ground- 
calculated position is RA, Dec = 231.204, -6.958 deg, which is
RA (J2000) = 15h 24m 49s
Dec(J2000) = -06d 57' 29"
with an uncertainty of 2.87 arcmin (90% confidence, including  
systematics). The detection was triggered by simultaneous independent  
detections of 35.6 sigma and 20.2 sigma from imaging in the 15-50 keV  
and 50-150 keV energy bands, respectively. The burst mask-tagged  
lightcurve lightcurve in the 15-150 keV band shows a strong and broad  
emission peak starting at T+21sec, lasting 29 sec, and peaking twice  
at T+25sec and T+30sec. T90 = 20.4sec and T50 = 8.0sec.

The time-averaged spectrum over the 55 sec exposure time of the source  
is best fit by a power law with an exponential cutoff, with photon  
index 1.02 and high-energy cut at 133 keV. The fluence in the 15-150  
keV band is 3.1 x 10^-6 erg/cm^2, and and the peak 1-sec flux is 2.5   
10^-7 erg/cm^2/sec at T+30sec. A follow-up Swift ToO observation for  
this burst has been scheduled.


GRB_name: GRB090307A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8945
SUBJECT: GRB 090307: Swift-BAT refined analysis of trigger 345551
DATE:    09/03/07 17:07:38 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
P. A. Evans (U Leicester), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+303 sec from recent telemetry downlinks,
we report further analysis of posible GRB 090307 (trigger #345551)
(Evans, et al., GCN Circ. 8943).  The BAT ground-calculated position is
RA, Dec = 245.007, -28.647 deg, which is 
   RA(J2000)  =  16h 20m 01.7s 
   Dec(J2000) = -28d 38' 48.2" 
with an uncertainty of 3.3 arcmin, (radius, sys+stat, 90% containment).
We note that this position is based on a weak peak in the image domain (5.5 sigma).
This is lower than our regular detections because this is a Subthreshold
trigger.  The partial coding was 87%.
 
The mask-weighted light curve shows a weak pulse starting at ~T-7 sec and
ending at ~T+20 sec.  T90 (15-350 keV) is 22 +- 8 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-7.4 to T+16.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.08 +- 0.39.  The fluence in the 15-150 keV band is 2.6 +- 0.6 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+5.57 sec in the 15-150 keV band
is 0.2 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/345551/BA/

Given the weak nature of this event and the as yet unconfirmed nature
of this trigger by the XRT follow-up observations, we can not rule out
that this trigger is due something other than a GRB.  There are further
XRT follow-up observations in the observing plan.


GRB_name: GRB090307A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8946
SUBJECT: GRB 090307: Swift-XRT afterglow confirmation and analysis
DATE:    09/03/08 13:54:58 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Swift-XRT observed the field of GRB 090307 (BAT trigger 345551; GCN
Circs. 8943, 8945) for 4.6 ks, from 135 s to 80 ks after the BAT
trigger. All of the data were taken in Photon Counting (PC) mode.  The
X-ray source reported by Evans et al. (GCN Circ. 8943) is seen to fade,
and is therefore identified as the afterglow, confirming the GRB nature
of this BAT trigger. The source has an enhanced XRT position: RA, Dec =
244.9944, -28.6333 which is equivalent to:

RA (J2000): 16 19 58.64
Dec (J2000): -28 37 59.9

with an uncertainty of 2.1 arcsec (radius, 90% confidence). The light
curve shows a power-law decay, with an index 0.7 (+0.2, -0.1).

The PC mode spectrum can be fitted with an absorbed power-law, with a
photon index of 2.21 (+0.72, -0.60) and an absorbing column of 3.5
(+2.7,-1.1) e21 cm-2, in excess of the Galactic value of 1.3e21 cm-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.1 x 10-11 (7.6 x 10-11) erg cm-2
count-1.

If the light curve continues to decay with alpha=0.7, the XRT count-rate
at T+48 hrs will be 0.002 counts s-1, corresponding to an observed
(unabsorbed) 0.3-10 keV flux of 7.38e-14 (1.4e-13) erg cm-2 s-1.

The results of the automatic XRT analysis are available online at
http://www.swift.ac.uk/xrt_products/00345551.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090306B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8947
SUBJECT: GRB 090306B: Possible XRT afterglow
DATE:    09/03/08 13:58:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Swift-XRT observed the field of the BAT Slew Survey burst GRB 090306B 
(Copete et al. GCN Circ. 8944) for 5.8 ks, from T0+67 ks to T0+81 ks. The 
data were entirely in PC mode.

A single, faint source is found in the BATSS error circle, with a position 
RA,Dec = 231.2083, -6.9682 which is equivalent to:

RA (J2000)  = 15 24 49.99
Dec (J2000) = -06 58 05.6

with an uncertainty of 4.0 arcsec (radius, 90% confidence).

We currently have only 16 counts from this source, at a count rate of 3.5 
(+/- 0.9) e-3 counts s-1, and are unable to ascertain whether it is 
fading.

Further observations, to verify the nature of this source, are planned.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090308A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8948
SUBJECT: GRB 090308: Swift detection of a burst
DATE:    09/03/08 18:21:15 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

P. A. Evans (U Leicester), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC),
R. Margutti (Univ Bicocca&OAB), C. B. Markwardt (CRESST/GSFC/UMD),
F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),
C. Pagani (PSU), K. L. Page (U Leicester), A. M. Parsons (GSFC),
P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-IASFPA),
R. L. C. Starling (U Leicester), M. C. Stroh (PSU),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 18:01:23 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090308 (trigger=345777).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 183.526, -48.833 which is 
   RA(J2000) = 12h 14m 06s
   Dec(J2000) = -48d 49' 57"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  This is an image trigger, but even so
the BAT light curve shows a weak peak at T+20 to T+35 sec. 
The peak count rate was ~350 counts/sec (15-350 keV), at ~25 sec
after the trigger. 

The XRT began observing the field at 18:03:30.4 UT, 126.9 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 183.5017,
-48.8169 which is equivalent to:
   RA(J2000)  = 12h 14m 0.41s
   Dec(J2000) = -48d 49' 00.9"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 81 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (8.54e+20
cm^-2, Kalberla et al. 2005), with an excess column of 1.8
(+1.51/-1.36) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 131 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. Because part of the 2.7'x2.7'
sub-image was not received, there is no overlap with the XRT error circle. 
The 8'x8' region for the list of sources generated on-board covers the entire
XRT error circle. No correction has been
made for the expected extinction corresponding to E(B-V) of 0.11. 

Burst Advocate for this burst is P. A. Evans (pae9 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB090308A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8949
SUBJECT: GRB 090308: Swift-BAT refined analysis
DATE:    09/03/08 21:02:11 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

C. B. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), P. A. Evans (U Leicester), E. E. Fenimore (LANL),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090308 (trigger #345777)
(Evans, et al., GCN Circ. 8948).  The BAT ground-calculated position is
RA, Dec = 183.545, -48.754 deg, which is 
   RA(J2000)  =  12h 14m 10.7s 
   Dec(J2000) = -48d 45' 13.8" 
with an uncertainty of 3.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 89%.
 
The mask-weighted light curve shows a single peak starting at ~T-10 sec,
peaking at ~T+30 sec, and ending at ~T+65 sec.  T90 (15-350 keV) is
48 +- 22 sec (estimated error including systematics).
 
The time-averaged spectrum from T+4.0 to T+52.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.33 +- 0.37.  The fluence in the 15-150 keV band is 2.6 +- 0.6 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+27.50 sec in the 15-150 keV band
is 0.1 +- 0.0 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/345777/BA/


GRB_name: GRB081007A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8951
SUBJECT: Radio observation of GRB 081007 with ATCA
DATE:    09/03/09 05:43:46 GMT
FROM:    Aquib Moin at CIRA/ATNF  <aquib.moin@postgrad.curtin.edu.au>

Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope
National Facility), Steven Tingay (Curtin Institute of Radio Astronomy),
Chris Phillips (Australia Telescope National Facility), Gregory Taylor
(University of New Mexico), Mark Wieringa (Australia Telescope National
Facility) and Ralph Martin (Perth Observatory) report:

We observed the SWIFT-UVOT position of the GRB081007 afterglow (GCN
8330) at 4.800 and 4.928 GHz with the Australia Telescope Compact Array
(ATCA) between 01:00:00 UT and 22:00:00 UT on February 21/22, 2009.

We did not detect a radio source at the position of the GRB081007
afterglow (GCN 8330). The data at 4.800 and 4.928 GHz were merged and
the radio flux density at the GRB optical afterglow position found out
to be -0.215 +/- 0.006 mJy/beam (1-sigma).

The Australia Telescope Compact Array (/ Parkes telescope / Mopra
telescope / Long Baseline Array) is part of the Australia Telescope
which is funded by the Commonwealth of Australia for operation as a
National Facility managed by CSIRO.

See the 4.800 & 4.928 GHz combined image at:

http://cira.ivec.org/dokuwiki/doku.php/grb/grb081007/grb081007_field_image 


GRB_name: GRB081226A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8952
SUBJECT: Radio observation of GRB 081226a with ATCA
DATE:    09/03/09 06:03:08 GMT
FROM:    Aquib Moin at CIRA/ATNF  <aquib.moin@postgrad.curtin.edu.au>

Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope
National Facility), Steven Tingay (Curtin Institute of Radio Astronomy),
Chris Phillips (Australia Telescope National Facility), Gregory Taylor
(University of New Mexico), Mark Wieringa (Australia Telescope National
Facility) and Ralph Martin (Perth Observatory) report:

We observed the GROND position of the GRB081226a afterglow (GCN 8731) at
4.800 and 4.928 GHz with the Australia Telescope Compact Array (ATCA)
between 01:00:00 UT and 22:00:00 UT on February 21/22, 2009.

We did not detect a radio source at the position of the GRB081226a (GCN
8731). The data at 4.800 and 4.928 GHz were merged and the radio flux
density at the GRB optical afterglow position found out to be 0.115 +/-
0.180 mJy/beam (1-sigma).

The Australia Telescope Compact Array (/ Parkes telescope / Mopra
telescope / Long Baseline Array) is part of the Australia Telescope
which is funded by the Commonwealth of Australia for operation as a
National Facility managed by CSIRO.

See the 4.800 & 4.928 GHz combined image at:

http://cira.ivec.org/dokuwiki/doku.php/grb/grb081226a/grb081226a_field_image


GRB_name: GRB081226B
Detection_method: IBAS
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8953
SUBJECT: Radio observation of GRB 081226b with ATCA
DATE:    09/03/09 06:10:48 GMT
FROM:    Aquib Moin at CIRA/ATNF  <aquib.moin@postgrad.curtin.edu.au>

Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope
National Facility), Steven Tingay (Curtin Institute of Radio Astronomy),
Chris Phillips (Australia Telescope National Facility), Gregory Taylor
(University of New Mexico), Mark Wieringa (Australia Telescope National
Facility) and Ralph Martin (Perth Observatory) report:

We observed the INTEGRAL-IBAS position of the GRB081226b (GCN 8734) at
4.800 and 4.928 GHz with the Australia Telescope Compact Array (ATCA)
between 01:00:00 UT and 22:00:00 UT on February 21/22, 2009.

We did not detect a radio source at the position of the GRB081226b (GCN
8734). The data at 4.800 and 4.928 GHz were merged and the radio flux
density at the GRB position found out to be -0.176 +/- 0.196 mJy/beam
(1-sigma).

The Australia Telescope Compact Array (/ Parkes telescope / Mopra
telescope / Long Baseline Array) is part of the Australia Telescope
which is funded by the Commonwealth of Australia for operation as a
National Facility managed by CSIRO.

See the 4.800 & 4.928 GHz combined image at:

http://cira.ivec.org/dokuwiki/doku.php/grb/grb081226b/grb081226b_field_image


GRB_name: GRB090117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8954
SUBJECT: Radio observation of GRB 090117 with ATCA
DATE:    09/03/09 06:29:00 GMT
FROM:    Aquib Moin at CIRA/ATNF  <aquib.moin@postgrad.curtin.edu.au>

Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope
National Facility), Steven Tingay (Curtin Institute of Radio Astronomy),
Chris Phillips (Australia Telescope National Facility), Gregory Taylor
(University of New Mexico), Mark Wieringa (Australia Telescope National
Facility) and Ralph Martin (Perth Observatory) report:

We observed the SuperAGILE-GRID position of the GRB090117 (GCN 8817) at
4.800 and 4.928 GHz with the Australia Telescope Compact Array (ATCA)
between 01:00:00 UT and 22:00:00 UT on February 21/22, 2009.

We did not detect a radio source at the position of the GRB090117 (GCN
8817). The data at 4.800 and 4.928 GHz were merged and the radio flux
density at the GRB position found out to be -0.0109 +/- 0.189 mJy/beam
(1-sigma).

The Australia Telescope Compact Array (/ Parkes telescope / Mopra
telescope / Long Baseline Array) is part of the Australia Telescope
which is funded by the Commonwealth of Australia for operation as a
National Facility managed by CSIRO.

See the 4.800 & 4.928 GHz combined image at:

http://cira.ivec.org/dokuwiki/doku.php/grb/grb090117/grb090117_field_image 


GRB_name: GRB090201A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8955
SUBJECT: Radio observation of GRB 090201 with ATCA
DATE:    09/03/09 06:56:08 GMT
FROM:    Aquib Moin at CIRA/ATNF  <aquib.moin@postgrad.curtin.edu.au>

Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope
National Facility), Steven Tingay (Curtin Institute of Radio Astronomy),
Chris Phillips (Australia Telescope National Facility), Gregory Taylor
(University of New Mexico), Mark Wieringa (Australia Telescope National
Facility) and Ralph Martin (Perth Observatory) report:

We observed the VLT position of the GRB090201 optical afterglow (GCN
8873) at 4.800 and 4.928 GHz with the Australia Telescope Compact Array
(ATCA) between 01:00:00 UT and 22:00:00 UT on February 21/22, 2009.

We did not detect a radio source at the optical afterglow position of
the GRB090201 (GCN 8873). The data at 4.800 and 4.928 GHz were merged
and the radio flux density at the afterglow position found out to be
-0.430 +/- 0.280 mJy/beam (1-sigma).

The Australia Telescope Compact Array (/ Parkes telescope / Mopra
telescope / Long Baseline Array) is part of the Australia Telescope
which is funded by the Commonwealth of Australia for operation as a
National Facility managed by CSIRO.

See the 4.800 & 4.928 GHz combined image at:

http://cira.ivec.org/dokuwiki/doku.php/grb/grb090201/grb090201_field_image 


GRB_name: GRB090308A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8956
SUBJECT: GRB 090308: Swift-XRT refined analysis
DATE:    09/03/09 07:33:46 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P. A. Evans and K.L. Page (U Leicester) report on behalf of the 
Swift-XRT team:

We have analysed 4.4 ks of XRT data for GRB 090308 (Evans et al. GCN
Circ. 8948), from 130 s to 12.2 ks after the BAT trigger. The data
comprise 55 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. Using 460 s of PC mode data and 1 UVOT image, we
find an enhanced XRT position (using the XRT-UVOT alignment and matching
UVOT field sources to the USNO-B1 catalogue): RA, Dec = 183.50120,
-48.81710 which is equivalent to:

RA (J2000): 12 14 0.28
Dec(J2000): -48 49 01.6

with an uncertainty of 1.6 arcsec (radius, 90% confidence).

The light curve can be modelled with an initial power-law decay with an
index of alpha=2.63 (+0.16, -0.13), followed by a break at T+830 s to an
alpha of 1.2 (+0.5, -1.9).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.93 (+0.28, -0.26). The
best-fitting absorption column is 2.86 (+1.01, -0.88) x 10^21, in excess
of the Galactic value of 8.5 x 10^20 cm^-2 (Kalberla et al. 2005). The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.5 x 10^-11 (6.8 x 10-11) erg cm^-2
count^-1.

If the light curve continues to decay with a power-law decay index of
1.9, the count rate at T+24 hours will be 2.0 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.1 x 
10^-15 (1.4 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00345777.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB090305C
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8957
SUBJECT: GRB 090305C: Suzaku WAM observation of the prompt emission
DATE:    09/03/09 09:36:28 GMT
FROM:    Makoto Tashiro at Saitama U/Swift  <tashiro@phy.saitama-u.ac.jp>

GRB 090305C: Suzaku WAM observation of the prompt emission

W. Iwakiri, M. Tashiro, Y. Terada, Y. Urata, A. Endo, K. Onda,
N. Kodaka, K. Morigami, T. Sugasahara (Saitama U.),
T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), S. Sugita,
K. Yamaoka (Aoyama Gakuin U.), M. Ohno, M. Kokubun, M. Suzuki,
T. Takahashi (ISAS/JAXA), Y. E. Nakagawa, T. Tamagawa (RIKEN),
T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata (Hiroshima U.),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori, K. Kono,
H. Hayashi, (Univ. of Miyazaki), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The IPN localized short GRB 090305C (Golenetskii et al., GCN 8941)
triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an
energy range of 50 keV - 5 MeV at 17:19:38.326 UT (=T0).

The observed light curve shows a multi-peaked structure starting at T0
+0.2s, ending at T0+1.3s with a duration (T90) of about 0.9 seconds.
The fluence in 100 - 1000 keV was 1.85(-0.58, +0.13)x 10^-06 erg/cm2.
The 0.5-s scaled peak flux measured from T0+0s was 4.13(-0.97, +0.19)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0+0s
to T0+1.5s is fitted by a power-law with exponential cutoff model:

dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha 1.05(-0.49, 0.38), and
Epeak 835 ( -237, 618) keV (chi^2/d.o.f. = 5.20/13).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB090306B
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8958
SUBJECT: GRB 090306B: GROND Upper Limits
DATE:    09/03/09 13:29:06 GMT
FROM:    Christian Clemens at MPE  <cclemens@mpe.mpg.de>

A. C. Updike (Clemson University), C. Clemens, J. Greiner and P. Afonso (MPE 
Garching) report on behalf of the GROND team:

We observed the field of GRB 090306B (BATSS, Copete et al., GCN #8944) 
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) 
mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory (Chile).

Observations started at 04:34 UT on March 8th, about 29.5 hours after the GRB 
trigger, and lasted 45 min.

We do not detect a source within the Swift-XRT error circle reported by Evans 
(GCN #8947) down to (all in AB system)

g' > 23.2,
r' > 23.6,
i' > 23.3,
z' > 23.0,
J > 21.7,
H > 21.0 and
K > 20.1.

The given limits are derived based on calibrating the images against GROND 
zeropoints and 2MASS field stars and are not corrected for the Galactic 
foreground extinction corresponding to a reddening of E_(B-V)= 0.11 in the 
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB090307A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8959
SUBJECT: GRB 090307: GROND Upper Limits
DATE:    09/03/09 13:45:36 GMT
FROM:    Christian Clemens at MPE  <cclemens@mpe.mpg.de>

A. C. Updike (Clemson University), C. Clemens, J. Greiner and P. Afonso (MPE 
Garching) report on behalf of the GROND team:

We observed the field of GRB 090307 (Swift trigger 345551; Barthelmy et al., 
GCN #8945) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, 
PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory 
(Chile).

Observations started at 05:06 UT on March 7, 80 min after the GRB trigger, and 
continued for 66 min. They were performed at an average seeing of 1.2" and at 
an average airmass of 1.8.

We do not detect a source within the Swift-XRT error circle reported by Evans 
et al. (GCN #8946) down to (all in AB system)

g' > 23.3,
r' > 23.7,
i' > 23.2,
z' > 22.9,
J > 21.7,
H > 21.2 and
K > 20.3.

The given limits are derived based on calibrating the images against GROND 
zeropoints and 2MASS field stars and are not corrected for the Galactic 
foreground extinction corresponding to a reddening of E_(B-V)= 0.528 in the 
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB090306C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8960
SUBJECT: GRB 090306C: Fermi GBM detection
DATE:    09/03/09 14:59:13 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

Arne Rau (MPE) reports on behalf of the Fermi GBM Team:

"At 05:52:05.35 UT on 06 March 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090306C (trigger 258011527  / 090306245).

The on-ground calculated location, using the GBM trigger
data, is RA = 135.0, DEC = +51.7 (J2000 degrees,
equivalent to 09 h 00 m, 51 d 36 '), with an uncertainty
of 5.5 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 14 degrees.

The GBM light curve shows one main peak lasting about 5s followed by a 
broader tail
with a total duration (T90) of about 38.8 s (8-1000 keV).
The time-averaged spectrum from T0-4.096 s to T0+6.144 s is
adequately fit by a power law function with an exponential
high energy cutoff at 107 +/- 16 keV and  with index -0.58 +/- 0.29
(chi squared 380 for 381 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(9.0 +/- 2.2)E-07 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.024 s in the 8-1000 keV band
is 2.4 +/- 0.1 ph/s/cm^2.

A Band function fits the spectrum equally well (chi squared 378 for 380 
d.o.f.)
with Epeak= 87 +/- 25 keV, alpha = -0.32 +/- 0.54 and beta = -2.28 +/-0.43.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


GRB_name: GRB090307B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  8961
SUBJECT: GRB 090307B: Fermi GBM detection
DATE:    09/03/09 15:16:17 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs@mpe.mpg.de>

E.Bissaldi (MPE) and A. von Kienlin (MPE) 
report on behalf of the Fermi GBM Team: 


"At 04:00:58.60 UT on 07 March 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090307B (trigger 258091199 / 090307167).

The on-ground calculated location, using the GBM trigger
data, is RA = 158.6, DEC = -14.6 (J2000 degrees,
equivalent to 10h 34m, -14d 36'), with an uncertainty
of 9.7 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 83 degrees.

This long GRB consists of one main FRED-like pulse with
substructure, rising at T0-6 s and with a duration (T90)
of about 30 s (8-1000 keV). T50 is about 15 s (8-1000 keV).
The time-averaged spectrum from T0-6 s to T0+10.4 s is
best fit by a power law function with an exponential
high energy cutoff. The power law index
is -0.7 +/- 0.3 and the cutoff energy, parameterized as
Epeak, is 212 +/- 80 keV (chi squared 346 for 357 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.7 +/- 0.4)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T0-5 s in the 8-1000 keV band
is 1.80 +/- 0.12 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."


