# GCN_circulars

GRB_name: GRB100424A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10668
SUBJECT: GRB 100424A: Prompt enhanced Swift-XRT position.
DATE:    10/04/24 17:10:26 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:

Using 1.4 ks of promptly downlinked XRT data and 1 promptly available UVOT image
we find an enhanced position of the XRT afterglow of GRB 100424A (Hoversten et
al., GCN Circ. 10667) of RA, Dec 209.4478, 1.5386 which is equivalent to:
   RA(J2000)  = 13h 57m 47.44s
   Dec(J2000) = +01d 32' 18.8"
with an uncertainty of 2.0 arcseconds (radius, 90% containment). Analysis of the
promptly available data is online at http://www.swift.ac.uk/sper/420367.

Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and
Evans et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100424A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10669
SUBJECT: GRB 100424A: Enhanced Swift-XRT position
DATE:    10/04/24 22:50:55 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 1406 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 100424A, 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 = 209.44775, +1.53897 which is equivalent
to:

RA (J2000): 13h 57m 47.46s
Dec (J2000): +01d 32' 20.3"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100424A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10670
SUBJECT: GRB 100424A, Swift-BAT refined analysis
DATE:    10/04/24 23:50:55 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@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), E. A. Hoversten (PSU),
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+243 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 100424A (trigger #420367)
(Hoversten et al., GCN Circ. 10667).  The BAT ground-calculated position
is RA, Dec = 209.453, 1.512 deg which is
    RA(J2000)  =  13h 57m 48.6s
    Dec(J2000) = +01d 30' 44.2"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 88%.

The mask-weighted lightcurve shows a single broad peak from about T+20
to T+150 sec.  T90 (15-350 keV) is 104 +- 15.5 sec (estimated error
including systematics).

The time-averaged spectrum from T+22.3 to T+148.5 sec is best fit by
a simple power-law model.  The power law index of the time-averaged
spectrum is 1.83 +- 0.13.  The fluence in the 15-150 keV band is
1.5 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from
T+58.28 sec in the 15-150 keV band is 0.4 +- 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/420367/BA/


GRB_name: GRB100424A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10671
SUBJECT: GRB 100424A: NOT optical observations
DATE:    10/04/25 01:19:23 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

D. Malesani (DARK/NBI), D. Xu (Weizmann Inst.), A. J. Levan (Univ. 
Warwick), P. Jakobsson (Univ. Iceland), T. Pursimo (NOT), report on 
behalf of a larger collaboration:

We observed the field of GRB 100424A (Hoversten et al., GCN 10667) with 
the NOT equipped with ALFOSC in the R, I, and z filters. Observations 
started on April 24 at 22:38, 23:05, and 23:31 UT in R, I, z, 
respectively (6.30, 6.74, and 7.21 hr after the GRB), and were affected 
by the closeby bright Moon (42 deg away, 85% full) and some clouds.

We do not detect any new object within the refined XRT error circle 
(Evans, GCN 10668; Evans et al., GCN 10669). The limiting magnitudes are 
R(Vega) = 22.5 and z(AB) = 21.9, calibrated against the USNO-B1 and SDSS 
catalogs, respectively.

Given the relatively large X-ray flux, we encourage NIR observations.


GRB_name: GRB100424A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10672
SUBJECT: GRB 100424A: WHT z-band observations
DATE:    10/04/25 02:12:06 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan, C. Copperwheat, E. Breedt (U. Warwick), D. Malesani
(DARK/NBI) report on behalf of a larger collaboration:

"We observed the localization of GRB 100424A (Hoversten et al. GCN
10667) using the WHT and ACAM. Observations begin at April 25 00:18,
approximately 9 hours after the burst. We obtained 4x200s exposures
in the z-band. No source is visible within the enhanced XRT location
(Evans et al. GCN 10669)  to a limiting magnitude of z>23.2, calibrated
against SDSS. 

The deep z-band limit, coupled with apparently bright early X-ray
afterglow is suggestive of either a highly extinguished, or high
redshift burst."


GRB_name: GRB100425A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10673
SUBJECT: GRB 100425A: Swift detection of a burst
DATE:    10/04/25 03:03:20 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

D. Grupe (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (NASA/UMBC), S. T. Holland (CRESST/USRA/GSFC),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the
Swift Team:

At 02:50:45 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100425A (trigger=420398).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 299.187, -26.441 which is 
   RA(J2000) = 19h 56m 45s
   Dec(J2000) = -26d 26' 27"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed two peaks, one with a 
duration of about 8 sec at T0 and one of about 6 sec at T+38 sec.  The 
peak count rate was ~500 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 02:52:03.9 UT, 78.8 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 299.19593,
-26.43039 which is equivalent to:
   RA(J2000)  = 19h 56m 47.02s
   Dec(J2000) = -26d 25' 49.4"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 47 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
8.59e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 3.11e-09 erg cm^-2 s^-1 (0.2-10
keV). 



UVOT took a finding chart exposure of 150 seconds with the White filter
starting 88 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 19.6 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
0.15. 

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: GRB100424A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10674
SUBJECT: GRB 100424A: Swift-XRT refined analysis
DATE:    10/04/25 04:13:36 GMT
FROM:    Michael Stroh at PSU/Swift  <stroh@astroh.org>

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

We have analysed 641 s of XRT data for GRB 100424A (Hoversten  et al.
GCN Circ. 10667), from 126 s to 769 s after the  BAT trigger. The data
comprise 509 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The light curve can be modelled with a
series of power-law decays. The initial decay index is alpha=0.63
(+/-0.14). At T+288 s the decay steepens to an alpha of 1.41 (+0.27,
-0.19) before breaking again at T+526 s to a final decay with index
alpha=2.8 (+0.9, -0.6).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.26 (+/-0.06). The
best-fitting absorption column is 1.62 (+0.22, -0.21) x 10^21 cm^-2,
in excess of the Galactic value of 2.3 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 5.8 x 10^-11 (6.5 x 10^-11) erg
cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of
2.8, the count rate at T+24 hours will be 5.1 x 10^-6 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.0 x
10^-16 (3.3 x 10^-16) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00420367.

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


GRB_name: GRB100424A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10675
SUBJECT: GRB 100424A: PAIRITEL NIR Upper Limits
DATE:    10/04/25 06:14:03 GMT
FROM:    Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>

A. N. Morgan and J. S. Bloom (UC Berkeley) report:

We observed the field of GRB 100424A (Hoversten et al., GCN 10667)
with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations
began at 2010-04-25 03:51:19 UT, ~11.3 hours after the Swift Trigger,
under high airmass.  In  mosaics (effective exposure time of 0.74
hours) taken simultaneously in the J, H, and Ks filters, we do not
detect any source within the enhanced XRT error circle (Evans et al.,
GCN 10669).

The preliminary photometry yields:

post burst
t_mid (hr) exp.(hr) filt  U. Limit (3 sig)
11.81      0.74     J     > 19.3
11.81      0.74     H     > 18.4
11.81      0.74     Ks    > 17.0

Further observations are ongoing to obtain a deeper limit.  All
magnitudes are given in the Vega system, calibrated to 2MASS. No
correction for Galactic extinction has been made to the above reported
values.


GRB_name: GRB100424A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10676
SUBJECT: GRB 100424A: GROND Upper Limits
DATE:    10/04/25 06:32:41 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

F. Olivares, T. Kruehler and J. Greiner (all MPE Garching) report on 
behalf of the GROND team:

We observed the field of GRB 100424A (Swift trigger 420367; Hoversten et 
al., GCN 10667) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 
2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla 
Observatory (Chile).

Observations started at 00:16 UT on April 25, 7.7 hours after the GRB 
trigger, and continued for 3 hours. The observations were severely 
affected by passing cirrus clouds.

In our first stacked images of 24 min total integration time in g'r'i'z' 
and 20 min in JHK, we do not (see also Malesani et al., GCN 10671, Levan 
et al., GCN 10672, Morgan & Bloom GCN 10675) detect a source within the 
enhanced Swift/XRT error circle (Evans et al., GCN 10669) down to the 
following preliminary 3 sigma limiting magnitudes (all in the AB system):

g' > 23.03
r' > 23.37
i' > 22.96
z' > 23.04
J > 21.77
H > 21.21
K > 20.29

Later images do not increase these limiting magnitudes due to worse sky 
conditions. These limits were derived by calibrating the images against 
SDSS/2MASS field stars and are not corrected for the Galactic foreground 
extinction corresponding to a reddening of E_(B-V)= 0.03 in the 
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB100424A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10677
SUBJECT: GRB 100424A : Lulin early z'-band upper limit
DATE:    10/04/25 07:46:11 GMT
FROM:    Yuji Urata at Nat. Central U.  <urata@astro.ncu.edu.tw>

K.Y. Huang (ASIAA), Y. Urata, P. Tsai (NCU) on behalf of EAFON report;

We observed the field of GRB 100424A (Hoversten et al., GCN 10667) in
r' and z'-band with the LOT. Observations started at 17:52 UT on April 24, 
~80 min after the Swift Trigger. In our z'-band stacked image shows
no new object within the enhanced Swift/XRT position (Evans et al.,
GCN 10669) down to the following preliminary limiting magnitudes,

----------------------------
Time(hr)  Filter   Limit(AB)
----------------------------
2.16      z'       20.6
----------------------------


GRB_name: GRB100423A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10678
SUBJECT: GRB100423A: MITSuME optical upper limits
DATE:    10/04/25 08:13:10 GMT
FROM:    Daisuke Kuroda at OAO/NAOJ  <dikuroda@oao.nao.ac.jp>

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


We observed the field of GRB 100423A (Stroh et al. GCNC 10651)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.
The observation started on 2010-04-23 13:27:35 UT (~12.9h after the
burst). We could not detect the previously reported afterglow
(Filgas et al., GCN 10652) in all the three bands.

Three sigma upper limits of the OT are listed below. We used SDSS
catalog for flux calibration.


T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.59033   14:45:04  4500.0      >18.9  >19.0  >18.4
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]


GRB_name: GRB100424A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10679
SUBJECT: GRB100424A: MITSuME optical upper limits
DATE:    10/04/25 08:14:00 GMT
FROM:    Daisuke Kuroda at OAO/NAOJ  <dikuroda@oao.nao.ac.jp>

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


We observed the field of GRB 100424A (Hoversten et al. GCNC 10667)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.
The observation started on 2010-04-24 16:34:56 UT (~2.2 min after
the burst). We did not find any new point source within the XRT
error circle (Evans, GCNC 10668; Evans et al., GCNC 10669) in all
the three bands.

Three sigma upper limits of the OT are listed below. We used SDSS
catalog for flux calibration.


T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.00527    16:40:18   540.0     >18.4  >18.5  >17.7
0.04356    17:35:26  5940.0     >19.6  >20.0  >19.4
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]


GRB_name: GRB100425A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10680
SUBJECT: GRB 100425A: candidate optical afterglow from the VLT
DATE:    10/04/25 08:44:36 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

D. Malesani (DARK/NBI), A. J. Levan (Univ. Warwick), N. R. Tanvir (Univ. 
Leicester), J. P. U. Fynbo (DARK/NBI), P. Goldoni (APC/Univ. Paris 7 and 
SAp/CEA), report on behalf of a larger collaboration:

We are observing the field of GRB 100425A (Grupe et al., GCN 10673) with 
the ESO VLT equipped with the X-shooter spectrograph.

In the R-band acquisition image, taken starting around 06:51 UT 
(approximately 4 hr after the GRB), we detect two sources within the 
refined XRT error circle (http://www.swift.ac.uk/sper/), at coordinates:

A: RA(J2000) = 19:56:47.30, Dec(J2000) = -26:25:49.3
B: RA(J2000) = 19:56:47.13, Dec(J2000) = -26:25:50.1

Source A is visible in the DSS, and has a similar magnitude to its 
archival value. Source B is not readily visible in the DSS and has a 
magnitude R = 20.55 +- 0.2, which is at the limit of the DSS 
sensitivity. The large error comes mostly from calibration scatter in 
comparison with USNO-B1 stars.

In a second image taken starting at 7:44 UT (4.9 hr after the GRB), 
source B has faded by 0.17 +- 0.08 mag.

Given the consistency of its position with the XRT error circle and the 
moderate evidence for variability, we propose source B as the optical 
afterglow of GRB 100425A.

A finding chart from the X-shooter image can be seen at the following URL:

http://www.astro.ku.dk/~malesani/GRB/100425A/GRB100425A_finder.png

Further observations and analysis are ongoing. We acknowledge a 
particularly helpful and attentive support from the ESO staff in 
Paranal, especially Jonathan Smoker, Lorena Faundez, Manuel Olivares 
and Steffen Mieske.


GRB_name: GRB100424A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10681
SUBJECT: GRB 100424A: D50 optical limits
DATE:    10/04/25 09:35:32 GMT
FROM:    Jan Strobl at AI AS CR,Ondrejov  <jan@strobl.cz>

Jan Strobl (1), Martin Jelinek (2), Cyril Polasek (1), Petr Kubanek (2,3),
Martin Nekola (1), Matus Kocka (1), Michal Jakubec (1) and Rene Hudec (1)
(1. ASU AVCR Ondrejov, 2. IAA Granada, 3. GACE Valencia)

We observed the field of Swift GRB 100424A (Hoversten et al., GCNC 10667) 
with the 0.5m telescope D50 in Ondrejov (Czech Republic), starting at 
23:27:02 UT, i.e. 06:54:20 after the trigger. A sequence of 20s unfiltered 
images was obtained. We coadded 60x20s exposure, obtaining an image with a 
limitting magnitude Rc~19.3, with an effective exposure time 7.35h after 
the trigger (23:54UT). We do not detect any new source within the XRT 
localization (Evans et al., GCN10699).

This message can be cited.


GRB_name: GRB100424A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10682
SUBJECT: GRB 100424A: Gemini/NIRI Candidate Afterglow
DATE:    10/04/25 09:47:55 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, J. S. Bloom, A. N. Morgan, and B. E. Cobb (UC Berkeley)
report on behalf of a larger collaboration:

We have imaged the field of GRB 100424A (Hoversten et al., GCN 10667) with
the Near-InfraRed Imager and Spectrometer mounted on the 8 m Gemini North
telescope.  Observations were taken in the J and K filters beginning at
6:28 UT on 25 April 2010 (~ 14 hours after the burst).

At the edge of the refined XRT error circle (Evans et al., GCN 10669) we
identify a faint point source in both filters.  Referencing both the
astrometry and photometry to the 2MASS source 13574681+0131477, we
measure a position (J2000) of

 RA: 13:57:47.43  Dec: +01:32:18.9

and approximate magnitudes of K = 19.9, J = 22.1 (both Vega magnitudes).
The J-K color indicates a red afterglow, though does not necessarily
require a high-redshift origin (e.g., Levan et al., GCN 10672).  No
other objects are detected inside the XRT error circle.

Without evidence for variability, we cannot definitively confirm if this
source is the afterglow of GRB 100424A.  Further observations are planned
to search for fading.

We wish to thank the staff at Gemini Observatory, in particular Kristin
Chiboucas, for promptly executing these observations.


GRB_name: GRB100425A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10683
SUBJECT: GRB 100425A: GROND afterglow observation
DATE:    10/04/25 10:46:55 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

F. Olivares, T. Kruehler and J. Greiner (all MPE Garching) report on 
behalf of the GROND team:

We observed the field of GRB 100425A (Swift trigger 420398; Grupe et 
al., GCN 10673) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 
2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla 
Observatory (Chile).

Observations started at 05:17 UT on April 25, 2.4 hours after the GRB 
trigger, and were initially performed through thin cloud coverage.

The optical afterglow candidate reported by Malesani et al. (GCN 10680, 
source 'B') is found to be clearly variable. Between 2.9 and 5.9 hours 
after the burst, the source decayed roughly 0.5 mag in the r' band. At a 
midtime of 08:45 UT we measure the following preliminary magnitudes (all 
in the AB system) in stacked images with a total integration time of 24 
min in g'r'i'z' and 20 min in JHK:

g = 21.5 +- 0.2
r = 21.0 +- 0.1
i = 20.8 +- 0.1
z = 20.5 +- 0.1
J = 20.1 +- 0.2
H = 19.9 +- 0.2
K = 19.6 +- 0.2

calibrated against the GROND zeropoints and 2MASS field stars, and not 
corrected for the expected foreground extinction of E(B-V)=0.15 
(Schlegel et al. 1998).


GRB_name: GRB100425A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10684
SUBJECT: GRB 100425A: VLT/X-shooter redshift
DATE:    10/04/25 12:27:35 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

P. Goldoni (APC/Univ. Paris 7 and SAp/CEA), H. Flores (Paris Obs.), D. 
Malesani (DARK/NBI), A. J. Levan (Univ. Warwick), N. R. Tanvir (Univ. 
Leicester), J. P. U. Fynbo (DARK/NBI), report on behalf of a larger 
collaboration:

We observed the optical afterglow of GRB 100425A (Grupe et al., GCN 
10673; Malesani et al., GCN 10680; Olivares et al., GCN 10683) with th 
ESO VLT equipped with the X-shooter spectrograph. Four spectra lasting 
10 minutes each were obtained, covering the spectral range 3000-25000 
AA, starting on 2010 April 25, at 6:53 UT (4.0 hr after the GRB).

We detect the traces of both objects lying within the XRT error circle. 
Preliminary inspection of the spectrum of the afterglow reveals several 
absorption features which we interpret as due to Mg II and Fe II, at a 
common redshift z = 1.755.

We caution that the data reduction was carried out using archival 
calibration files. We acknowledge a particularly helpful and attentive 
support from the ESO staff in Paranal, especially Jonathan Smoker, 
Lorena Faundez, Manuel Olivares and Steffen Mieske.


GRB_name: GRB100425A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10685
SUBJECT: GRB 100425A: Swift-BAT refined analysis
DATE:    10/04/25 13:38:39 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), N. Gehrels (GSFC), D. Grupe (PSU),
H. A. Krimm (GSFC/USRA), 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-61 to T+242 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 100425A (trigger #420398)
(Grupe, et al., GCN Circ. 10673).  The BAT ground-calculated position is
RA, Dec = 299.161, -26.463 deg, which is 
   RA(J2000)  =  19h 56m 38.7s 
   Dec(J2000) = -26d 27' 47.8" 
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 48%.
 
The mask-weighted light curve shows three peaks.  A first, precursor peak
at ~T-45 sec, then the main peak at T-2 sec to ~T+10 sec, and the third peak
at T+35 to ~T+65 sec.  T90 (15-350 keV) is 37.0 +- 2.4 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-2.1 to T+39.4 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.42 +- 0.32.  The fluence in the 15-150 keV band is 4.7 +- 0.9 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.27 sec in the 15-150 keV band
is 1.4 +- 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/420398/BA/
 


GRB_name: GRB100425A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10686
SUBJECT: GRB 100425A: Enhanced Swift-XRT position
DATE:    10/04/25 14:13:23 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 5331 s of XRT Photon Counting mode data and 8 UVOT
images for GRB 100425A, 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 = 299.19651, -26.43069 which is equivalent
to:

RA (J2000): 19h 56m 47.16s
Dec (J2000): -26d 25' 50.5"

with an uncertainty of 1.5 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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100424A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10687
SUBJECT: GRB 100424A: Liverpool Telescope Upper Limits
DATE:    10/04/25 14:25:15 GMT
FROM:    Zach Cano at ARI/John Moores Liverpool  <zec@astro.livjm.ac.uk>

Z. Cano, A. Melandri (Liverpool JMU), C. Guidorzi (U. Ferrara), C.
Mundell, R.J. Smith, D. Bersier, I.A. Steele, S. Kobayashi, C.J. Mottram,
(Liverpool JMU), A. Gomboc (U. Ljubljana) report, on behalf of a larger
collaboration:

We observed the field of GRB 100424A (Hoversten et al. GCNC 10667) with
the Liverpool Telescope starting 20:54 UT on April 24, 2010.  We do not
detect the NIR afterglow discovered by Cenko et al. (GCN 10682), nor any
other object within the enhanced XRT error circle (Evans, GCN 10668; Evans
et al., GCN 10669) down to the following limits:

-------------------------------------------------------------------
 Mid Exposure        Total
  T-To (hrs)   Exposure Time (min)     Filter          upper limit
-------------------------------------------------------------------
     6.91              30                 B              >21.5
     6.92              50                 I              >21.8
     8.38              20                 R              >21.7
-------------------------------------------------------------------

The upper limits are for an isolated object in our images and are
calibrated using nearby stars in the USNO-B1 catalogue.  No correction for
Galactic extinction has been made.


GRB_name: GRB100424A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10688
SUBJECT: GRB 100424A: Swift/UVOT Upper Limits
DATE:    10/04/25 14:39:39 GMT
FROM:    Peter Curran at MSSL  <pac@mssl.ucl.ac.uk>

P.A. Curran (MSSL-UCL) and E. Hoversten (PSU) report on behalf of the
Swift/UVOT team:


The Swift/UVOT began settled observations of the field of GRB 100424A 
128 s after the BAT trigger (Hoversten et al., GCN Circ. 10667). No 
optical afterglow consistent with the refined XRT position (Evans et 
al., GCN Circ. 10669) or the proposed NIR counterpart (Cenko et al. (GCN 
Circ. 10682) is detected in the initial UVOT exposures.

Preliminary 3-sigma upper limits using the UVOT photometric system 
(Poole et al. 2008, MNRAS, 383, 627) for the initial finding charts (FC) 
and exposures are:

Filter   T_start(s) T_stop(s)   Exp(s)   Mag
----------------------------------------------
white    128         278        147      >20.8 (FC)
u        288         537        246      >20.0 (FC)
white    128        2046        444      >21.2
v        618        1930        156      >19.2
b        543        2028        156      >20.1
u        288        2003        382      >20.1
w1       668        1979        156      >19.7
m2       642        1955         97      >19.1
w2       594        5584        193      >20.0


The values quoted above are not corrected for the Galactic extinction 
due to the reddening of E(B-V) = 0.08 in the direction of the burst 
(Schlegel et al. 1998).


GRB_name: GRB100425A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10689
SUBJECT: GRB100425A: Swift/UVOT Upper Limits
DATE:    10/04/25 18:00:55 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (MSSL-UCL) and D. Grupe (PSU) report on behalf of the  
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 100425A 88s after the BAT trigger (Grupe et al., GCN 10673).
We do not detect a new source at the enhanced Swift XRT position
(Goad et al. GCN 10686) and at the location of source B detected
by the VLT telescope (Malesani  et al. GCN 10680) and GROND
telescope (Olivares et al. GCN 10683). Photometry is complicated
by the prescence of the VLT source A within the source aperture.

The 3-sigma upper limits for the finding chart exposures (FC)
and summed images are:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white (FC)  88      238      147         >19.37
white       88      5778     513         >19.59
u     (FC)  301     551      246         >18.92
u     301     6796     650         >19.08
v           631     11961    1317        >19.76
b           556     5573     236         >19.71
uvw1        680     6600     432         >19.44
uvm2        4757    12580    997         >20.87
uvw2        606     11048    1318        >21.26
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.15 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).


GRB_name: GRB100424A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10690
SUBJECT: GRB 100424A: Gemini/NIRI H-band observations
DATE:    10/04/26 07:27:45 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, A. N. Morgan, and J. S. Bloom (UC Berkeley) report on behalf
of a larger collaboration:

We have obtained further imaging of the field of GRB 100424A (Hoversten et
al., GCN 10667) with the Near InfraRed Imager and Spectrometer mounted on
the 8 m Gemini North telescope.  Following our report of a detection of a
candidate afterglow in the J and K filters (Cenko et al., GCN 10682), we
obtained a sequence of H-band images beginning at 9:29 UT on 25 April 2010
(~ 17 hours after the burst).

The candidate afterglow is also detected in the H-band.  Using the
PAIRITEL imaging of the field for photometric calibration (Morgan and
Bloom, GCN 10675), we measure a magnitude of H = 20.9 (Vega) at this time.

Combined with our previous J and K photometry (and assuming the afterglow
decays in time like a power-law with index alpha=-1), the candidate
infrared afterglow appears consistent with a relatively steep spectral
power-law index of beta ~ 2.5-3.0 across all three bands.  This suggests
the afterglow is reddened due predominantly to dust in the host galaxy of
the GRB, and not an extremely high-redshift (z > 7) origin, as would be
suggested by the presence of host galaxy extinction from the X-ray
afterglow spectrum (Stroh et al., GCN 10674).

We wish to thank the staff at Gemini Observatory for assistance in
executing these observations.


GRB_name: GRB100425A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10691
SUBJECT: GRB 100425A: Swift XRT refined analysis 
DATE:    10/04/26 17:26:13 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 14.2 ks of XRT data for GRB 100425A (Grupe et al.
GCN Circ. 10673), from 85 s to 81 ks after the BAT trigger. The
data consist of 106s in Windowed Timing mode (WT) and 14.1 ks
in  Photon Counting (PC) mode. The current XRT light curve can be
fit by a broken power law model with an initial decay slope of
5.3+/-0.3 with a beak at 330+/-20 s followed by a shallow decay
slope of 0.55+/- 0.05. The last data point at 77 ks after the
burst suggests a break at about 60ks. However, this is based on
one data point. Therefore, a prediction on the future behavior of
the  X-ray afterglow can not be given at this point.


A spectrum formed from the WT mode data can be fitted with an
absorbed power-law with a photon spectral index of 4.00 (+/-0.15).
The best-fitting absorption column density is
1.49 (+0.18, -0.17) x 10^22 cm^-2, at a redshift of 1.755
(Goldini et al. GCN Circ 10684), in addition to the Galactic value
of 8.6 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum
has a photon index of 2.30+/-0.13 and a best-fitting
absorption column density consistent with the Galactic value.
Based on this spectrum, the counts to observed (unabsorbed)
0.3-10 keV flux conversion  factor deduced from this spectrum is
3.77 x 10^-11 (5.17 x 10^-11) erg cm^-2 count^-1.

Swift will continue observing the X-ray afterglow of GRB 100425A
over the next few days.


The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00420398.

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


GRB_name: GRB100424A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10692
SUBJECT: GRB 100424A: NIR Afterglow Confirmation
DATE:    10/04/27 00:05:44 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, J. S. Bloom, D. A. Perley, A. N. Morgan, B. E. Cobb (UC
Berkeley) and A. J. Levan (U. Warwick) report on behalf of a larger
collaboration:

We have obtained a second epoch of K-band imaging of the field of GRB
100424A (Hoversten et al., GCN 10667) with the Near InfraRed Imager and
Spectrometer mounted on the 8 m Gemini North telescope.  Observations
began at 11:23 UT on 26 April 2010 (~ 43 hours after the burst).

The previously identified candidate in the XRT error circle (Cenko et al.,
GCN 10682) has faded by 0.9 +/- 0.1 mag, confirming the object is indeed
the NIR afterglow of GRB 100424A.  Assuming negligible contribution from
an underlying host galaxy, the inferred power-law decay index, alpha ~
0.7, is relatively shallow.

We wish to thank the staff at Gemini Observatory, in particular Kristin
Chiboucas, for executing these observations.


GRB_name: GRB100424A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10693
SUBJECT: GRB 100424A: CrAO optical observations
DATE:    10/04/27 07:54:33 GMT
FROM:    Alina Volnova at SAI MSU  <alinusss@gmail.com>

V. Rumyantsev, D. Shakhovskoy (CrAO), A. Volnova (SAI MSU), A.
Pozanenko (IKI)  report on behalf of larger GRB  follow-up
collaboration:

We observed the field of the Swift GRB 100424A (Hoversten et al., GCN
10667) with AZT-11 telescope of CrAO observatory between (UT) Apr. 24
18:01 - 19:18 under seeing of about 3 arcsec. We detected a  probable
source at coordinates (J2000) RA =  13:57:47.64 Dec = +01:32:21.06
with an uncertainty of 0.5 arcsec in both coordinates. The probable
source is located 2.8 arcsec from the enhanced XRT position with an
uncertainty (radius) of 1.7 arcsec (Evans et al., GCN 10669). Due to
low S/N we cannot confirm the detected source is a real object.

We do not detect any source at the position of afterglow candidate
(Cenko, et al., GCN 10682, Cenko, et al., GCN 10690).

The photometry of the probable source and upper limit of the
point-like source in a stacked image based on USNO-B1.0 star
(RA(J2000) = 13:57:45.54 Dec(J2000)= +01:33:29.7) and assuming R=17.80
is following:

T0+      Filter, Exposure, mag.           UL
(mid, d)         (s)

0.0882   R       21x180    20.1 +/- 0.3   20.4

The combined image can be found at
http://grb.rssi.ru/GRB100424A/GRB100424a_R_AZT11.gif


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10694
SUBJECT: GRB 100418A: Terskol optical observations
DATE:    10/04/27 09:50:55 GMT
FROM:    Alina Volnova at SAI MSU  <alinusss@gmail.com>

M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy),
A. Volnova (SAI MSU), A. Pozanenko (IKI) report on behalf of larger
GRB follow-up collaboration:

We observed the field of the Swift GRB 100418A (Marshall et al. GCN
10612) with the Z-600 telescope of Mt.Terskol observatory in R-filter
between (UT) Apr. 20 19:47 - 23:00 under good weather conditions with
mean seeing of about 1.6 arcsec. The optical afterglow (Marshall et al. GCN
10612, Filgas et al. GCN 10617) is clearly detected in enhanced XRT
error circle (Osborne et al. GCN 10614). The photometry of the
afterglow in a stacked image based on USNO-B1.0 star 1014-0271368
(RA(J2000) = 17:05:26.42 Dec(J2000)= +11:27:32.9) assuming R=17.32 is
following:

T0+    Filter,  Exposure,  mag.        UL
(mid, d)      (s)

2.0175  R     50x180    19.85 +/- 0.18  20.8


GRB_name: GRB100423A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10695
SUBJECT: GRB 100423A: CrAO optical observations
DATE:    10/04/27 09:52:28 GMT
FROM:    Alina Volnova at SAI MSU  <alinusss@gmail.com>

V. Rumyantsev, D. Shakhovskoy (CrAO), A. Volnova (SAI MSU), A.
Pozanenko (IKI)  report on behalf of larger GRB  follow-up
collaboration:

We observed the field of the Swift GRB 100423A (Stroh et al., GCN
10651) with AZT-11 telescope of CrAO Observatory between (UT) Apr. 23
18:15 - 18:46. We do not detect source at the position of the
afterglow (Filgas et al., GCN 10652; Ivarsen et al., GCN 10653).

The upper limit of the stacked image based on USNO-B1.0 star
1115-0180143  (RA(J2000) = 09 05 44.73  Dec(J2000)= +21 31 14.0) and
assuming R=17.21 is following:

T0+      Filter, Exposure, mag.
(mid, d)         (s)

0.7489   R       11x180    >20.7

The upper limit is compatible with power-law decay index -1.1 reported
by Ivarsen et al. (GCN 10653).


GRB_name: GRB100423A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10696
SUBJECT: Konus-Wind observation of GRB 100423A
DATE:    10/04/27 14:15:03 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100423A (Swift-BAT trigger=420247;
Stroh et al., GCN 10651; Cummings et al., GCN 10658)
triggered Konus-Wind at T0=02097.629s UT (00:34:57.629)

The burst light curve started with a hard short (~150 ms)
precursor followed (after ~0.6 s) by a FRED-like pulse
with a total duration of ~100 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100423_T02097/

As observed by Konus-Wind the burst
had a fluence of 4.8(+/-0.5)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+0.768s
of 8.3(+/-0.6)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+65.792 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -0.71 (-/+0.25),
the high energy photon index beta = -2.15 ( <-1.9 ),
the peak energy Ep = 455(-83, +194)keV (chi2 = 96/57 dof).

The spectrum at the maximum count rate
(measured from T0+0.256 to T0+8.848 s) is best fit
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.50(+/-0.15),
and Ep = 621(-67, +82) keV (chi2 = 74/58 dof).

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


GRB_name: GRB100414A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10697
SUBJECT: GRB 100414A : WSRT Radio Detection
DATE:    10/04/28 14:58:30 GMT
FROM:    Atish Kamble at U. of Amsterdam  <A.P.Kamble@uva.nl>

A.P. Kamble (U of Amsterdam), A.J. van der Horst (NASA/MSFC/ORAU),
R.A.M.J. Wijers, E. Rol (U of Amsterdam), C. Kouveliotou (NASA/MSFC)
and K. Wiersema (U of Leicester) report on behalf of a larger 
collaboration :

"We observed the field of Fermi GBM/LAT burst GRB 100414A (GCN 10594, 
10595, 10649) using the Westerbork Synthesis Radio Telescope at 4.8 GHz
from April 27, 16.0 UT to April 28, 04.0 UT, i.e. 13.57 to 14.1 days
after the burst. We detect the radio afterglow with flux density
of 420 +/- 38 microJy at the position of the optical afterglow
detected by GROND (GCN 10607).

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


GRB_name: GRB100414A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10698
SUBJECT: GRB 100414A : EVLA Radio Detection
DATE:    10/04/28 16:10:57 GMT
FROM:    Dale A. Frail at NRAO  <dfrail@nrao.edu>

Dale A. Frail (NRAO), Poonam Chandra (RMC), S. Bradley Cenko
(Berkeley) and Fiona Harrison (Caltech) report on behalf of a larger
collaboration:

"We used the Expanded Very Large Array (EVLA) to observe the field of
view towards the Fermi GBM/LAT burst GRB 100414A (GCN 10594, 10595,
10649) on April 27.18 UT at a center frequency of 8.46 GHz.  We detect
the radio afterglow with flux density of 397  15 microJy at the
position of the optical afterglow detected by GROND (GCN 10607).

Further observations are planned.

The EVLA is still undergoing active commissioning and we caution that
these results should be considered preliminary. The National Radio
Astronomy Observatory is a facility of the National Science Foundation
operated under cooperative agreement by Associated Universities, Inc."


GRB_name: GRB100427A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10699
SUBJECT: GRB 100427A detected in ground analysis of Swift BAT data
DATE:    10/04/28 16:25:05 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc@milkyway.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), H. A. Krimm (GSFC/USRA),
and R. L. C. Starling (U Leicester) on behalf of the Swift team:

At 08:31:55 UT Swift-BAT detected a rate increase. Onboard analysis
was terminated prematurely by a pre-planned slew, but in later
ground analysis a significant source was found at
RA, Dec 89.171,  -3.461, which is

RA  (J2000)    05h 56m 41.1s
Dec (J2000)   -03d 27' 40"

with an estimated uncertainty of 2.5 arcmin radius (90%
containment).

The burst had two main peaks, the first much weaker, from about
T-3 to T+3 sec and from T+11 to T+23 sec.  We have full data for
only the first, weaker peak.  The peak non-maskweighted count
rate (15-350 keV) was about 3000 counts/sec at 16 seconds after
the trigger.

Since the source was not detected onboard, there are no automated
data products for this burst.

A Swift TOO has started.


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10700
SUBJECT: GRB 100418A: RTT150 optical observations
DATE:    10/04/28 21:04:18 GMT
FROM:    Irek Khamitov at TUG  <irekk@tug.tug.tubitak.gov.tr>

I. Bikmaev (KSU/AST), I. Khamitov (TUG),
S. Melnikov, N. Sakhibullin (KSU/AST),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)

report:

The optical afterglow of GRB 100418A (Marshall et al., GCN 10612, Filgas
et al., GCN 10617) was observed with Russian-Turkish 1.5-m telescope
(RTT150, Bakirlitepe, TUBITAK National Observatory, Turkey) in April
23/24 and April 27/28, 2010, in partially cloudy conditions. We obtained
one useful 900 sec image in Rc-band in April 24 and nine 900 sec images
in April 28. In spite of bright Moon in April 27/28 observations OT is
clearly detected in combined image.

In the Table below we give our Rc estimates of the OT brightness
relative to the nearby USNO-B1.0 star 1014-0271368 (R2Mag=17.32).

Date     UT  (T-T0),h    Rc      err
Apr.24 00:20 123.1       20.6  +/-0.10
Apr.28 00:50 220.0       21.25 +/-0.05

Preliminary Rc-light curve can be found at:
http://hea.iki.rssi.ru/grb/100418a/indexeng.html

OT is still brighter compared with its host galaxy (Malesani, GCN10621)
and further spectroscopic and photometric observations of this event are
very important to check possible SN contribution in the OT flux.


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GRB_name: GRB100424A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10701
SUBJECT: GRB 100424a. Radio observations
DATE:    10/04/28 23:30:36 GMT
FROM:    Dale A. Frail at NRAO  <dfrail@nrao.edu>

Dale A. Frail (NRAO) and Poonam Chandra (RMC) report on behalf of a
larger collaboration:

"We observed the localization of GRB 100424A (Hoversten et al. GCN
10667) the Expanded Very Large Array (EVLA) on April 27.14 UT at a
center frequency of 8.46 GHz. We do not detect any radio source
anywhere within the refined XRT error circle (Evans et al., GCN 10669)
to a 3-sigma limit of 66 uJy.

The EVLA is still undergoing active commissioning and we caution that
these results should be considered preliminary. The National Radio
Astronomy Observatory is a facility of the National Science Foundation
operated under cooperative agreement by Associated Universities, Inc."


GRB_name: GRB100427A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10702
SUBJECT: GRB 100427A: Fermi GBM detection
DATE:    10/04/29 00:31:46 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (UAH) and D. Gruber (MPE) 
report on behalf of the Fermi GBM Team: 

"At 08:32:08.71 UT on 27 April 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100427A (trigger 294049930 / 100427356),
which was also detected by the Swift-BAT (J.R. Cummings et al. 2010, 
GCN 10699).  The GBM on-ground location is consistent with the Swift-BAT 
position.  The angle from the Fermi LAT boresight is 29 degrees.

The GBM light curve consists of a single pulse with multiple peaks
with a duration (T90) of about 24 s (8-1000 keV). 
The time-averaged spectrum from T0-4.1 s to T0+11.3 s is 
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.02 +0.12/-0.11 and
the cutoff energy, parameterized as Epeak, is 121.0 +15.4/-11.8 keV
(Castor C-Stat 519 for 484 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(3.01 +/- 0.13)E-06 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+5.18 s in the 8-1000 keV band 
is 4.79 +/- 0.24 ph/s/cm^2.

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


GRB_name: GRB100427A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10703
SUBJECT: GRB 100427A: Swift XRT and UVOT Upper Limits
DATE:    10/04/29 12:42:00 GMT
FROM:    Alice Breeveld at MSSL-UCL  <aab@mssl.ucl.ac.uk>

A. Breeveld (MSSL/UCL), A. Rowlinson, N. Lyons and R.L.C. Starling (U. 
Leicester) report on behalf of the Swift/UVOT team:

Swift began settled observations of the field of GRB 100427A 110220 s 
after the BAT rate increase detected in ground analysis (Cummings et 
al., GCN Circ. 10699). No afterglow consistent with the BAT position 
given in GCN Circ. 10699 is detected in the initial XRT or UVOT exposures.

Swift-XRT obtained 5.9 ks of Photon Counting (PC) mode data, from T0 + 
110 ks to T0 + 144 ks. No source is found in the BAT error circle, 
with a 3-sigma upper limit of 1.3 x 10-3 count s-1. For a typical GRB, 
this would correspond to an upper limit on the 0.3 - 10 keV flux of 5 
x 10-14 erg cm-2 s-1.

For the UVOT a preliminary 3-sigma upper limit for the initial summed 
exposures, using the UVOT photometric system (Poole et al. 2008, 
MNRAS, 383, 627),  is:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
u               110220       143784         5836         >21.2

The values quoted above are not corrected for the Galactic extinction 
due to the reddening of E(B-V) = 0.69 in the direction of the burst 
(Schlegel et al. 1998).


GRB_name: GRB100420A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10704
SUBJECT: GRB 100420A: Terskol optical upper limit
DATE:    10/04/29 13:28:30 GMT
FROM:    Alina Volnova at SAI MSU  <alinusss@gmail.com>

M. Andreev,  A. Sergeev (Terskol Branch of  Institute of Astronomy),
A. Volnova (SAI MSU), A. Pozanenko (IKI) report on behalf of larger
GRB follow-up collaboration:


We observed the field of the Swift GRB 100420A (Baumgartner et al.,
GCN 10628) with the Z-600 telescope of Mt.Terskol observatory in
R-filter between (UT) Apr. 20 23:30 - Apr. 21 00:39 under good weather
conditions with mean seeing of about 1.2 arcsec. We do not detect any
source at the position of the enhanced XRT error circle (Beardmore et
al., GCN 10638).

The 3 sigma upper limit of the stacked image based on several
USNO-B1.0 field stars is following:


T0+      Filter,  Exposure,  mag.
(mid, d)           (s)

0.7789   R       20x180    >20.2


GRB_name: GRB100423A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10705
SUBJECT: GRB 100423A: xinglong TNT optical upper limit
DATE:    10/04/29 16:50:42 GMT
FROM:    L.P. Xin at NAOC  <xlp@bao.ac.cn>

L.P. Xin, Z.X. Lin, Y.L. Qiu, J.Y. Wei,J. Wang, J.S. Deng, 
C. Wu, J.Y. Hu, on behalf of EAFON report:

We began to observe GRB100423A (Stroh et al., GCN 10651;
Filgas et al., GCN 10652; Ivarsen et al., GCN 10653) 
with Xinglong TNT telescope at 14:33:45(UT). The moon 
light was very bright. A series of R band images was 
obtained. No new source was found in the XRT errorbars 
within the combined 6*300s R band image. The 3 sigma upper 
limit is about 19.5 mag derived from USNO-B1.0,at the mean 
time of 14.2 hour after the burst.

This message may be cited.

For more information about Xinglong GRBs Follow-up
observations, please visit the website:
http://www.xinglong-naoc.org/grb/


GRB_name: GRB100420A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10706
SUBJECT: GRB 100420A: Gemini discovery of infrared afterglow
DATE:    10/04/29 22:01:47 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick), A. Cucchiara  (PSU), N.R. Tanvir (U.
Leicester), D. Fox (PSU) report on behalf of a larger collaboration:

"We obtained two epochs of observations of GRB 100420A (Baumgartner
et al. GCN 10628) using Gemini-North/NIRI. Our first epoch consisted
of 540s of observations in each of YJH and K and began at April 20
13:24 UT, approximately 8.2 hours after the burst. Our second epoch
was obtained at April 22 14:27 ~57 hours after the burst.

Within the refined XRT error circle we find a single object in our
first epoch K-band observation. The object has a location of

RA(J2000) 19:44:30.57
Dec(J2000) 55:46:10.0

with an error of 0.3" in each axis. It has a magnitude of K~21 in
our first epoch observation, but has faded below our 3-sigma detection
limit of K~22 in the second epoch. We therefore identify this source
as the infrared afterglow of GRB 100420A.

The source is not significantly detected in our J or H-band observations 
to preliminary limiting magnitudes of H>21.5, J>22.5 (3 sigma). However, 
because of the relative faintness of the K-band observations these limits
are not constraining in terms of high-z and dust extinguished
afterglow models"


GRB_name: GRB100420A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10707
SUBJECT: GRB 100420A: EVLA radio observations
DATE:    10/05/02 01:41:11 GMT
FROM:    Poonam Chandra at Royal Mil. College Canada  <Poonam.Chandra@rmc.ca>

Dale A. Frail (NRAO) and Poonam Chandra (RMC) report on behalf of a
larger collaboration:

"We observed the localization of dark burst GRB 100420A (Baumgartner 
et al. GCN 10628) with the Expanded Very Large Array (EVLA) on May 1.50 UT 
at a center frequency of 8.46 GHz.  We do not detect any radio source
anywhere within the refined XRT error circle (Beardmore et al., GCN 10638)
to a 3-sigma limit of 51 uJy.

The EVLA is still undergoing active commissioning and we caution that
these results should be considered preliminary.  The National Radio
Astronomy Observatory is a facility of the National Science Foundation
operated under cooperative agreement by Associated Universities, Inc."


GRB_name: GRB100423A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10709
SUBJECT: GRB100423A : Suzaku WAM observation of the prompt emission
DATE:    10/05/04 14:34:59 GMT
FROM:    Nicolas Vasquez at Tokyo Inst of Tech  <vasqpaz@gmail.com>

N. Vasquez (Tokyo Tech.), K. Yamaoka (Aoyama Gakuin U.), S. Sugita (Nagoya U),
T. Uehara, Y. Hanabata, T. Takahashi, Y. Fukazawa (Hiroshima U.),
Y. Terada, M. Tashiro, S. Hong, A. Endo, K. Onda, T. Sugasahara, W. Iwakiri

(Saitama U.), M. Ohno, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. E. Nakagawa, M. Suzuki, T. Tamagawa (RIKEN), N. Ohmori, A. Daikyuji,
E. Sonoda, K. Kono, H. Hayashi, K. Noda, Y. Nishioka, M. Yamauchi
(Univ. of Miyazaki), Y. Urata, H. M. Lin, P. Tsai

(NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo),
on behalf of the Suzaku WAM team, report:


The bright long, SWIFT GRB 100423A (TRIGGER_NUM:420247),
GNC 10651 (M. C. Stroh et. al.), Konus-Wind GCN10696 ( S. Golenetskii et. al.)

triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an
energy range
of 50 keV - 5 MeV at 00:34:57.78 UT (=T0).

The observed light curve shows a single peak FRED T0-1 s,
ending at T0+69 s with a duration (T90) of about 54 seconds.

The fluence in 100 - 1000 keV was 3.71(-0.22, +0.11)x10-5 erg/cm^2.

The 1-s peak flux measured from T0+1.5 s was 7.31(-0.35, +0.35)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from

T0-1 s to T0+69 s is well fitted by a GRB Band model as follows.

the low-energy photon index alpha: -0.43(-0.27, +0.31),
the high-energy photon index beta: -3.82(-1.33, +6.18),
and the peak energy Epeak: 649.8(-44.5, +44.5) keV (chi^2/d.o.f = 31/27).

All the errors are quoted at 90% confidence level.


The light curves for this burst are available at:
http://www.astro.isas.ac.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/1500.html


GRB_name: GRB100504A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10712
SUBJECT: GRB 100504A: Swift detection of a burst
DATE:    10/05/04 20:29:03 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>

J. Mao (INAF-OAB), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
A. de Ugarte Postigo (INAF-OAB), J. M. Gelbord (PSU),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC),
P. T. O'Brien (U Leicester), D. M. Palmer (LANL),
P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC),
G. Tagliaferri (INAF-OAB) and E. Troja (NASA/GSFC/ORAU) report on
behalf of the Swift Team:

At 19:20:59 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100504A (trigger=421124).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 255.572, -35.599 which is 
   RA(J2000) = 17h 02m 17s
   Dec(J2000) = -35d 35' 55"
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 ~2500 counts/sec (15-350 keV), at ~0 and ~10 sec after the trigger. 

The XRT began observing the field at 19:22:02.1 UT, 62.6 seconds after
the BAT trigger. Using promptly downlinked data we find a bright, fading,
uncatalogued X-ray source located at RA, Dec 255.57053, -35.58712 which
is equivalent to:
   RA(J2000)  = 17h 02m 16.93s
   Dec(J2000) = -35d 35' 13.6"
with an uncertainty of 4.1 arcseconds (radius, 90% containment). This
location is 42 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.  We
cannot determine whether the source is fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
3.61e+21 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 5.58e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 71 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. Because of the density of catalogued stars, further
analysis is required to report an upper limit for any afterglow in the
sub-image. The coverage of the XRT 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. Because of the density of catalogued
stars, further analysis is required to report an upper limit for any afterglow
in the region. No correction has been made for the large, but uncertain
extinction expected. 

Burst Advocate for this burst is J. Mao (jirong.mao AT brera.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: GRB100504A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10713
SUBJECT: GRB 100504A: UVOT-enhanced XRT position
DATE:    10/05/04 20:33:23 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao (INAF-OAB) reports on behalf of the Swift-XRT team:

The Swift-XRT observation of GRB 100504A started on 2010 May 4 at 
19:22:02.1 UT,
62.6 s after the BAT trigger. We detected a bright, single X-ray source. 
The UVOT-enhanced position is:

RA (J2000):  17h 02m 17.22s
Dec (J2000): -35d 35' 14.4''

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

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


GRB_name: GRB100503A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10714
SUBJECT: GRB 100503A: Fermi GBM detection
DATE:    10/05/04 21:01:06 GMT
FROM:    David Tierney at UCD  <david.tierney@ucd.ie>

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

"At 13:18:03.89 UT on 03 May 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100503A (trigger 294585485 / 100503554).

The on-ground calculated location, using the GBM trigger 
data, is RA = 147.5, DEC = 4.0 (J2000 degrees, 
equivalent to 09 h 50 m, 4 d 0 '), with an uncertainty 
of 1.5 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 63 degrees.

The GBM light curve consists of multiple peaks
with a duration (T90) of 129.5 +/- 9.9 s (50-300 keV). 
The time-averaged spectrum from T0-4 s to T0+52 s is 
best fit by a power law function with an exponential
high energy cutoff. The power law index is -0.99 (+0.06/-0.05)
and the cutoff energy, parameterized as Epeak, 
is 211.60 (+18.30/-15.50) keV (Cstat 877 for 601 d.o.f.).

The event fluence (10-1000 keV) in this time interval is 
(1.23 +/- 0.03)E-5 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+46.5 s in the 10-1000 keV band 
is 5.8 +/- 0.2 ph/s/cm^2.

A Band function fits the spectrum equally well 
(Cstat 871 for 600 d.o.f.) with Epeak= 162.60 (+21.60/-17.00) keV, 
alpha = -0.85 (+0.09/-0.09) and beta = -2.24 (+0.13/-0.21). 


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


GRB_name: GRB100504A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10715
SUBJECT: GRB 100504A: SARA-South Upper Limit
DATE:    10/05/05 02:31:36 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 100504A (Mao et al., GCN 10712) using the
0.6m SARA-South telescope located at CTIO under good conditions and high
airmass beginning 6 hours and 42 min after the trigger.  We do not detect
a new source at the location of the UVOT-enhanced XRT position (Mao, GCN
10713) to a limiting magnitude of R = 20 mag (on comparison to the USNO
B1.0 catalog).  We note that the extinction at this galactic latitude is
significant; E(B-V) = 0.840 mag (Schlegel et al. 1998).


GRB_name: GRB100504A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10716
SUBJECT: GRB 100504A: Swift-BAT refined analysis
DATE:    10/05/05 04:01:19 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
J. Mao (INAF-OAB), C. B. Markwardt (GSFC/UMD), 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-239 to T+363 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100504A (trigger #421124)
(Mao, et al., GCN Circ. 10712).  The BAT ground-calculated position is
RA, Dec = 255.575, -35.590 deg, which is 
   RA(J2000)  =  17h 02m 18.1s 
   Dec(J2000) = -35d 35' 23.0" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 92%.
 
The mask-weighted light curve shows two overlapping peaks followed by a
weak third peak, starting at ~T-10 sec, peaking at T+0, T+8, and ~T+90 sec,
and ending at ~T+100 sec.  T90 (15-350 keV) is 97.3 +- 7.3 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-9.7 to T+102.2 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.76 +- 0.10.  The fluence in the 15-150 keV band is 2.4 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+7.60 sec in the 15-150 keV band
is 1.7 +- 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/421124/BA/


GRB_name: GRB100504A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10717
SUBJECT: GRB 100504A: GROND Upper limits
DATE:    10/05/05 05:09:43 GMT
FROM:    Felipe Olivares Estay at MPE  <felipe@mpe.mpg.de>

P. Schady, F. Olivares, R. Filgas and J. Greiner (MPE Garching) report
on behalf of the GROND team:

We observed the field of GRB 100504A (Swift trigger 421124; Mao et
al., GCN #10712) simultaneously in g'r'i'z'JHK with GROND (Greiner et
al. 2008, PASP, 120, 405) mounted at the 2.2 m MPI/ESO telescope at La
Silla Observatory (Chile).

Observations started at 01:30 UT on May 5 (about 6.2 hours after the
GRB trigger). They were performed at a high airmass.

We do not detect a source within the Swift UVOT-enhanced XRT error
circle (Mao et al. GCN #10713) in any of the GROND filters. Coadded
images of 24 min of integration in g'r'i'z' and 20 min in JHK yield
the following 3-sigma upper limits:

g' > 23.2
r' > 22.2
i' > 21.6
z' > 21.2
J > 19.4
H > 19.1
K > 18.9

We note the presence of two uncatalogued sources 3" North-West of the
enhanced XRT position with magnitudes r' = 19.8 and J = 18.0 for the
more southern of the two, and r' = 20.2 and J = 18.6 for the second
source. Observations are continuing.

All magnitudes given above are in the AB system and are based on the
GROND zeropoints and 2MASS field stars. No correction has been applied
for the large, uncertain Galactic foreground extinction corresponding
to a reddening of E_(B-V)~ 0.8 in the direction of the burst (Schlegel
et al. 1998).


GRB_name: GRB100504A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10718
SUBJECT: GRB 100504A: Enhanced Swift-XRT position
DATE:    10/05/05 06:41:50 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 1124 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 100504A, 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 = 255.57137, -35.58742 which is equivalent
to:

RA (J2000): 17h 02m 17.13s
Dec (J2000): -35d 35' 14.7"

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. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100504A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10719
SUBJECT: GRB 100504A: Swift-XRT refined analysis
DATE:    10/05/05 07:34:12 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao (INAF-OAB) reports on behalf of the Swift-XRT team:

We have analysed 8.7 ks of Swift XRT data for GRB 100504A (Mao et al. 
GCN Circ. 10712). The data comprise 120 s in Windowed Timing (WT) mode 
with the remainder in Photon Counting (PC) mode.

The light curve shows evidence of flaring in WT mode, peaking at about 
83 s, after that, the light curve can be modelled with a broken 
power-law in PC mode, with an initial decay index of 
alpha1=3.04(+/-0.57) and breaking to a decay of index 
alpha2=0.57(+/-0.06), the break time is about 450 s.

A spectrum formed from the WT mode data can be fitted with an absorbed 
power-law with a photon spectral index of 1.95 (+/-0.09). The 
best-fitting absorption column is 9.07 (+/-0.71) x 10^21 cm^-2, in 
excess of the Galactic value of 3.77 x 10^21 cm^-2 (Kalberla et al. 
2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion 
factor deduced from this spectrum is 5.96 x 10^-11 (9.31 x 10^-11) erg 
cm^-2 count^-1.

The spectrum formed from the PC mode data can be fitted with an absorbed 
power-law with a photon spectral index of 2.40 (+/-0.37) and the 
absorption column density is consistent with the Galactic one in the GRB 
direction. The counts to observed (unabsorbed) 0.3-10 keV flux 
conversion factor deduced from this spectrum is 5.56 x 10^-11 (6.72 x 
10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 
0.57, the count rate at T+24 hours will be 6.9 x 10^-3 count s^-1, 
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.8 x 
10^-13 (4.6 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/00421124.

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


GRB_name: GRB100418A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10720
SUBJECT: GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
DATE:    10/05/05 20:10:36 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F.E. Marshall (NASA/GSFC) and S.T. Holland (CRESST/USRA/GSFC) 
report on behalf of the Swift/UVOT team:

The Swift/UVOT has monitored the optical flux from GRB 100418A 
since shortly after the BAT trigger (Marshall et al., GCN Circ. 10612).
The highest flux was seen at about T+50 ks, followed by a power-law
decay with an index of -1.0 +/- 0.1 in the UVOT white filter 
(Siegel et al., GCN Circ. 10645). The power-law decay continued
until about T+700 ks, after which time the flux has remained
approximately constant at about 22.3 mag in the white filter
through the latest observation at about T+1.2 Ms.
This late plateau may be due to flux from the host galaxy
(Malesani, GCN Circ. 10621). We note that the white magnitude is 0.6 mag
brighter than the SDSS g magnitude, but this may be due to
the very different filter responses. Other possibilities for the plateau
include a very bright SN (Malesani, GCN Circ. 10621; Filgas et al.,
GCN Circ. 10644) or optical flaring, which was seen earlier
in the light curve (Bikmaev, GCN Circ. 10635; Covino et al.,
GCN Circ. 10646). 

Swift continues to monitor GRB 100418A and observations with other
telescopes are encouraged.

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.07 (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB100504A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10721
SUBJECT: GRB 100504A: Swift/UVOT Observations
DATE:    10/05/05 21:46:28 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel@astro.psu.edu>

M. H. Siegel (PSU) and J. Mao (INAF-OAB) report on behalf
of the Swift/UVOT team.

The Swift/UVOT began settled observations of the field of
GRB 100504A 72s after the BAT trigger (Mao et al.,
GCN Circ. 10712).  Data summed from the first and second orbits
do not reveal a source at the enhanced position of the X-ray
afterglow (Mao et al., GCN Circ. 10713).

The 3-sigma upper limits for the finding chart (fc) and
summed exposures are reported below:

FILTER     T_start(s)  T_stop    Exposure     Mag/3UL
========================================================
white fc      72        222        147        >20.39
white         73       1705        391        >20.91
v            614       1755        136        >18.54
b            713       1680         97        >19.35
u           1463       1816         45        >18.43
uvw1         836       1804         97        >18.92
uvw2         762       1037         38        >18.43
=======================================================

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.87 (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB100504A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10723
SUBJECT: GRB 100504A: Fermi GBM observation
DATE:    10/05/06 17:10:53 GMT
FROM:    Vandiver Chaplin at UAH/Fermi-GBM  <chapliv@email.uah.edu>

V.Chaplin (UAH) reports on behalf of the Fermi GBM Team:

"At 19:20:55.53 UT on 04 May 2010, the Fermi Gamma-ray Burst Monitor  
(GBM)
triggered on GRB 100504A (trigger 294693657 / 100504.806), which
was also seen by Swift,BAT (J.Mao et al., GCN 10712).  The calculated
GBM ground position is consistent with the Swift,BAT position.
The angle from the Fermi LAT boresight is 104 degrees.

The GBM light curve shows a single pulse with a duration (T90)
of about 16 s (50-300 keV). The time-averaged spectrum from T0-6.1 to  
T0+23.6 s
is best fit by a power-law with an exponential high-energy cutoff.
The power-law index is -0.82 (+0.17/-0.16), and the cutoff energy,
parameterized as Epeak, is 85.7 (8.0/-6.6) keV (C-stat 960.7 for 481  
DOF).
The fluence (10-1000 keV) in this time interval is (2.7 +/- 0.12)E-06  
erg/cm^2.

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


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10726
SUBJECT: GRB 100418A: RTT150 optical observations
DATE:    10/05/07 03:44:59 GMT
FROM:    Irek Khamitov at TUG  <irekk@tug.tug.tubitak.gov.tr>

I. Bikmaev (KSU/AST), I. Khamitov (TUG), N. Sakhibullin (KSU/AST),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)

report:

The optical afterglow of GRB 100418A (Marshall et al., GCN 10612, Filgas
et al., GCN 10617) was observed with Russian-Turkish 1.5-m telescope
(RTT150,Bakirlitepe, TUBITAK National Observatory, Turkey) every night
during May 1/2 - 6/7, 2010.

We obtained  4 - 12 exposures by 900 sec each in Rc filter.
Estimates of Rc magnitudes were made relative to the nearby
USNO-B1.0 star 1014-0271368 (R2Mag=17.32).

Additionally we made  4 x 900 sec exposures in g',r',i' SDSS filters
in May 5/6, 2010.   OT is still existed in all filters as compared with 
SDSS host images.

We found that OT brightness has decreased from Rc = 21.25 in April 28
(Bikmaev et al., GCN 10700, T+0.792 Ms) to Rc = 21.60 +/- 0.05 in May 5, 
2010 (T+1.48 Ms) following a power-law decay with an index of -0.8 +/- 0.1,
without plateau reported by Marshall et al. (GCN10720).

In May 7, UT(mean) = 0h50m,  we estimated Rc = 21.7+/-0.07 mag.
It means that OT is began to fade faster after T+1.48 Ms.

-- 
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GRB_name: GRB100418A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10727
SUBJECT: GRB 100418A: Keck imaging
DATE:    10/05/07 23:19:17 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, S. B. Cenko, A. A. Miller, D. Poznanski, A. V. Filippenko, 
J. S. Bloom (UC Berkeley), and P. Nugent (LBNL) report:

We imaged the field of GRB 100418A (Marshall et al., GCN 10612) with the 
Low Resolution Imaging Spectrometer on the Keck I 10-m telescope during 
morning twilight on 2010-05-06 UT.  Two exposures of 380 seconds each 
were acquired in the g and R bands simultaneously.  The midpoint of the 
observation was 14:54 UT, 17.739 days after the GRB.

At the position of the afterglow and calibrating to 9 nearby unsaturated 
SDSS stars, we measure magnitudes of:

g = 22.67  0.07
R = 21.85  0.05

The g-band magnitude is marginally consistent with the SDSS magnitude 
(Malesani et al., GCN 10621) of g = 22.89  0.17, and suggests that the 
UVOT flattening (Marshall et al., GCN 10720) is primarily due to the 
host galaxy, not an associated supernova.  Our reported R-band magnitude 
is significantly brighter than the host, but this excess is consistent 
with an afterglow origin (Bikmaev et al., GCN 10726).  Additional 
follow-up observations will be necessary to comment on the presence (or 
absence) of a supernova counterpart.


GRB_name: GRB100508A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10728
SUBJECT: GRB 100508A: Swift detection of a burst
DATE:    10/05/08 09:53:16 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

R. Margutti (INAF-OAB), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), S. Campana (INAF-OAB),
A. de Ugarte Postigo (INAF-OAB), P. A. Evans (U Leicester),
J. M. Gelbord (PSU), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), C. B. Markwardt (CRESST/GSFC/UMD),
P. T. O'Brien (U Leicester), B. Sbarufatti (INAF-OAB/IASFPA),
G. Tagliaferri (INAF-OAB) and T. N. Ukwatta (GSFC/GWU) report on
behalf of the Swift Team:

At 09:20:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100508A (trigger=421386).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 76.250, -20.721 which is 
   RA(J2000) = 05h 05m 00s
   Dec(J2000) = -20d 43' 14"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is usual for an image trigger, the BAT light curve 
shows nothing of note. 

The XRT began observing the field at 09:23:09.7 UT, 147.5 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 76.2456,
-20.7114 which is equivalent to:
   RA(J2000)  = 05h 04m 58.95s
   Dec(J2000) = -20d 42' 41.1"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 37 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 (2.37e+20
cm^-2, Kalberla et al. 2005), with an excess column of 2.3
(+2.14/-1.86) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 151 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 19.6 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
0.03. There is a possible uncataloged object within the XRT error circle, but
due to analysis complications we cannot confirm the validity. 

Burst Advocate for this burst is R. Margutti (raffaella.margutti AT brera.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: GRB100508A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10729
SUBJECT: GRB 100508A: ROTSE-III Optical Limits
DATE:    10/05/08 10:19:32 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

B. E. Schaefer (Louisiana State), L. Xiao (Louisiana State), S. B. Pandey 
(U Mich), report on behalf of the ROTSE collaboration:

ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to 
GRB 100508A (Swift trigger 421386; Margutti et al., GCN 10728), producing 
images beginning 156.8 s after the GCN notice time. An automated response 
took the first image at 09:23:19.1 UT, 156.8 s after the burst, under fair 
conditions. We took 10 5-sec, 10 20-sec and 10 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 or the XRT error circle; the field is not 
crowded. Individual images have limiting magnitudes ranging from 
16.3-16.6; we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
09:25:55.9   09:26:15.9        20     16.5          156.8       N


GRB_name: GRB100508A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10730
SUBJECT: GRB100508A: Swift/UVOT Detection of the Afterglow
DATE:    10/05/08 12:20:29 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W.B. Landsman (GSFC) and R. Margutti (INAF-OAB)  report on behalf of the 
Swift/UVOT team.

Swift/UVOT began settled observations of the field of GRB 100508A 
starting 152 s after the BAT trigger (Margutti et al. GCN Circ. 10728).  
An uncatalogued fading source is seen in the 2.7' x 2.7' rapidly 
available subimage within the XRT error circle at

     RA(J2000) = 05h 04m 58.99s
     Dec(J2000) = -20d 42' 41.1"

with an uncertainty of about 0.6 arc sec (radius, 90% containment),   
The initial estimated magnitudes are as follows:

Filter   T_start    Exp(s)      Mag  Err
----------------------------------------------
white       152       150     18.87  0.09
u           310       250     19.25  0.20
white       864       150     20.7   0.44
----------------------------------------------


The above magnitudes are not corrected for the Galactic extinction 
corresponding to a reddening of E_{B-V} = 0.87 (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT photometric system 
described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB100508A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10731
SUBJECT: GRB 100508A: Enhanced Swift-XRT position
DATE:    10/05/08 13:31:01 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 1306 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 100508A, 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 = 76.24555, -20.71171 which is equivalent
to:

RA (J2000): 05h 04m 58.93s
Dec (J2000): -20d 42' 42.2"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100508A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10732
SUBJECT: GRB 100508A: Swift-BAT refined analysis
DATE:    10/05/08 14:12:20 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
R. Margutti (INAF-OAB), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), 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 100508A (trigger #421386)
(Margutti, et al., GCN Circ. 10728).  The BAT ground-calculated position is
RA, Dec = 76.263, -20.744 deg, which is 
   RA(J2000)  =  05h 05m 03.1s 
   Dec(J2000) = -20d 44' 36.8" 
with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 70%.
 
The mask-weighted light curve shows a broad peak starting at ~T-25 sec
and ending around T+200 sec with a very weak tail out to around T+400 sec.
T90 (15-350 keV) is 52 +- 10 sec (estimated error including systematics).
 
The time-averaged spectrum from T-8 to T+59 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.23 +- 0.25.  The fluence in the 15-150 keV band is 7.0 +- 1.1 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+6.04 sec in the 15-150 keV band
is 0.4 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.  One small caveate: the fluence and peak flux should be taken
as lower limits given that there are three 2-3 sec gaps (between 7 and 20 sec)
in the event-by-event data received on the ground.
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/421386/BA/


GRB_name: GRB100508A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10733
SUBJECT: GRB 100508A: Swift-XRT Refined analysis
DATE:    10/05/08 16:07:06 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti, B. Sbarufatti, A. de Ugarte Postigo (INAF-OAB)
report on behalf of the Swift-XRT team:

We have analysed 3.0 ks of XRT data for GRB 100508A (Margutti et al.
GCN Circ. 10728), from 132 s to 7.3 ks after the BAT trigger. The data
comprise 40 s in Windowed Timing (WT) mode (the first 9 s were taken while
Swift was slewing) with the remainder in Photon Counting (PC) mode.
The UVOT-enhanced XRT position was given by Beardmore al. in GCN Circ. 
10731.

The light curve can be modelled with an initial power-law decay with an 
index
of alpha=1.49 (+0.22, -0.18), followed by a break at T+694 s
to an alpha=0.39 (+0.08, -0.09).

A spectrum formed from the PC mode data can be fitted with an absorbed 
power-law
with a photon spectral index of 1.66 (+0.28, -0.27). The best-fitting 
absorption column
is 1.4 (+0.9, -0.7) x 10^21 cm^-2, in excess of the Galactic value of
2.4 x 10^20 cm^-2 (Kalberla et al. 2005). Uncertainties are given at 90% 
c.l.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor 
deduced from
this spectrum is 4.7 x 10^-11 (5.7 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 
0.39, the count
rate at T+24 hours will be 0.068 count s^-1, corresponding to an 
observed (unabsorbed)
0.3-10 keV flux of 3.2 x 10^-12 (3.9 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00421386.

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


GRB_name: GRB100508A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10734
SUBJECT: GRB 100508A: GROND Detection of the optical afterglow 
DATE:    10/05/09 04:36:20 GMT
FROM:    Patricia Schady at MPE/Swift  <pschady@mpe.mpg.de>

P. Schady, F. Olivares, (MPE Garching), A. Rossi (Tautenburg Obs.) and J.
Greiner (MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 100508A (Swift trigger 421386; Margutti et
al., GCN #10728) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla
Observatory (Chile).

Observations started at 22:50 UT on date, 13.5 hrs after the GRB trigger,
and were performed in poor seeing conditions and high airmass.

We detect an extended source in all four optical filters within the 1.7
Swift-XRT refined error circle reported by Beardmore et al. (GCN #10731),
and at a position consistent with the UVOT position reported by Landsman
et al. (GCN #10730).

Based on 15.3 min of total exposures in g'r'i'z' and 16 min in JHK, we
estimate preliminary magnitudes and upper limits in the optical and IR
respectively (all in AB system) of

g' = 22.0 +- 0.1 mag
r' = 21.8 +- 0.1 mag
i' = 21.5 +- 0.1 mag
z' = 21.7 +- 0.2 mag
J > 21.4
H > 20.8
K > 20.1

at the UVOT position using aperture photometry.

Given magnitudes are calibrated against GROND zeropoints as well as 2MASS
field stars and are not corrected for the expected Galactic foreground
extinction corresponding to a reddening of E_(B-V)=0.029 in the direction
of the burst (Schlegel et al. 1998). No correction has been applied to the
optical magnitudes for the possible contribution from the underlying host
galaxy.


GRB_name: GRB100503A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10735
SUBJECT: GRB100503A: Suzaku WAM observation of the prompt emission
DATE:    10/05/10 09:49:44 GMT
FROM:    Yoshitaka Hanabata at Hiroshima U  <hanabata@hep01.hepl.hiroshima-u.ac.jp>

Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.)
K. Yamaoka (Aoyama Gakuin U.), S. Sugita (Nagoya U.),
Y. Terada, M. Tashiro, W. Iwakiri, K. Takahara, T. Yasuda (Saitama U.),
M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. E. Nakagawa, T. Tamagawa (RIKEN), N. Ohmori, A. Daikyuji, Y. Nishioka,
M. Yamauchi (Univ. of Miyazaki), N. Vasquez (Tokyo Tech.), Y. Urata,
H. M. Lin (NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo),
S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:

The long GRB 100503A (Fermi/GBM trigger #294585485; Tierney et al.,
GCN 10714) triggered the Suzaku Wide-band All-sky Monitor (WAM) which
covers an energy of 50 keV - 5 MeV at 2010-05-03 13:18:51.17 UT (T=0).

The observed light curve shows a multi-peaked structure lasting from
T0-51s to T0+89s with T90 of about 103 seconds. The fluence in 100 -
1000 keV was 8.56 (-2.58, +2.10)x10^-6 erg/cm^2. The 1-s peak flux
measured from T0-1s was 1.23 (-0.27, +0.24) photons/cm^2/s in the
same energy range.

Preliminary result shows that the time-averaged spectrum from T0-51s
to T0+89s is well fitted by a single power-law with a photon index
of 2.04 (-0.29, +0.36) (chi^2/d.o.f = 11.1/11).

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

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


GRB_name: GRB100508A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10736
SUBJECT: GRB100508A: Further Swift/UVOT Observations
DATE:    10/05/10 13:38:18 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W.B. Landsman (GSFC) and R. Margutti (INAF-OAB)  report on behalf of 
the  Swift/UVOT team.

Swift/UVOT has continued observations of GRB100508A through 93,000s 
after the initial trigger (Margutti et al. GCN 10728).    The afterglow 
reported by Landsman and Margutti (GCN 10730)  was not detected in any 
filter past 12,000s after the initial trigger.     Magnitudes and 3 
sigma upper limits for selected exposures are reported below:

FILTER     T_start(s)     Exposure     Mag/3UL
=================================================
white fc     152            147        18.91  0.07
white        864            147        20.70  0.31
white      11708            295        21.22  0.30
u            310            246        19.16  0.15
u           6860            197        20.12  0.36
b           5634            197 > 20.7
v           6250            197 > 19.7
================================================


At late times our 3" photometry aperture includes the galaxy reported 
by  Schady et al. (GCN 10734), which may be the GRB host.   This galaxy 
is also listed in the SuperCosmos Sky Survey ( 
http://www-wfau.roe.ac.uk/sss/docs.html ) with coordinates 2.1" distant 
from the UVOT position.   The late-time white magnitude in a 6491s 
summed exposure taken between 57097s and 93249s after the trigger within 
the 3" aperture used to measure the afterglow is 21.86  0.12.

There are no detections or interesting magnitude limits in the UV filters.

The above magnitudes are not corrected for the Galactic extinction 
corresponding to a reddening of E(B-V) = 0.029 (Schlegel et al., 1998, 
ApJS, 500, 525). There was a typo in the value of E(B-V) reported for 
this burst by Landsman & Margutti (GCN 10730).   The photometry is on 
the UVOT photometric system described in Poole et al. (2008, MNRAS, 
383, 627).


GRB_name: GRB100511A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10738
SUBJECT: GRB 100511A, RIMOTS optical upper limits
DATE:    10/05/11 19:11:25 GMT
FROM:    Arata Daikyuji at Miyazaki U  <daikyu524@astro.miyazaki-u.ac.jp>

A.Daikyuji, N.Ohmori, Y.Nisioka, K.Noda, M.Yamauchi
(University of Miyazaki)

We have observed the field covering the error circle of
GRB GRB100511A (Swift trigger 421695)
with the unfiltered CCD camera on the 30-cm telescope
at University of Miyazaki.
The observation was started 14:19:42 UT, about two and
a half hours after the Swift trigger time.
We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog,
There is no new source at the reported position.

the upper limits are as follows:
--------------------------------------------------------------
Start(UT) End(UT) Num. of frames Limit (mag.)
--------------------------------------------------------------
14:19:42 14:20:12 1 14.9
14:19:42 15:02:15 26 16.0
---------------------------------------------------------------


GRB_name: GRB100510A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10739
SUBJECT: GRB 100510A: MAXI/GSC detection
DATE:    10/05/11 19:16:36 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

M. Morii (Tokyo Tech), M. Nakajima (Nihon U.), S. Nakahira (AGU),
N. Kawai, K. Sugimori (Tokyo Tech), M. Matsuoka, K. Kawasaki, S. Ueno,
H. Tomida, M. Kohama, M. Ishikawa (JAXA), T. Mihara, Y.E. Nakagawa,
M. Sugizaki, M. Suzuki, T. Yamamoto, T. Sootome (RIKEN), A. Yoshida,
K. Yamaoka (AGU), H. Tsunemi, M. Kimura (Osaka U.), H. Negoro, H. Ozawa,
F. Suwa (Nihon U.), Y. Ueda, N. Isobe, S. Eguchi, K. Hiroi (Kyoto U.),
A. Daikyuji (Miyazaki U.), A. Uzawa, T. Matsumura, K. Yamazaki (Chuo U.)
report on behalf of the MAXI team

MAXI/GSC detected a bright X-ray transient at a scan transit from
2010-05-10T19:27:09 to 19:27:37 UT. The transient emission lasted at least
for 28 seconds within the 50 second long triangular transit response of
MAXI/GSC.
This event is temporary coincident with the Fermi-GBM Trigger #295212428 at
2010-05-10T19:27:06.97, thus we identify this event as GRB 100510A.

The best-fit position of the source is
(R.A., Dec) = (+355.8 deg, -35.6 deg) = (23 43 10, -35 37 25)(J2000),
with a rectangular statistical error box (90%C.L.) of the following corners:

 (R.A., Dec) = (+355.69 deg, -35.79 deg) = (23 42 45, -35 47  8)(J2000)
 (R.A., Dec) = (+355.58 deg, -35.55 deg) = (23 42 19, -35 32 49)(J2000)
 (R.A., Dec) = (+355.90 deg, -35.46 deg) = (23 43 35, -35 27 38)(J2000)
 (R.A., Dec) = (+356.00 deg, -35.70 deg) = (23 44  1, -35 41 56)(J2000).

There is additional systematic uncertainty of 0.2 deg (90% containment radius).

Without assumptions on the source constancy, we obtain a rectangular error
box for the transient source with the following corners:

 (R.A., Dec) = (+355.18 deg, -35.92 deg) = (23 40 43, -35 55 12)(J2000)
 (R.A., Dec) = (+355.08 deg, -35.68 deg) = (23 40 18, -35 40 49)(J2000)
 (R.A., Dec) = (+356.70 deg, -35.24 deg) = (23 46 47, -35 14 11)(J2000)
 (R.A., Dec) = (+356.81 deg, -35.47 deg) = (23 47 14, -35 28 27)(J2000).

The peak X-ray flux was at least 650 +- 70 mCrab (4-10 keV, 1 sigma error).

The position above is consistent with the Fermi-GBM flight position
on 2010-05-10T19:27:33 UT (record #58, RA=345.10, Dec=-20.03, error=18.37),
but outside of the ground position on 2010-05-10T19:27:40 UT (record #57,
RA=31.87, Dec=-31.55, error=19.12).

The all-sky image and the light curve will be shown at the MAXI web site
http://maxi.riken.jp/ at the "News" section.


GRB_name: GRB100504A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10740
SUBJECT: GRB100504A: Optical upper limits at IAO
DATE:    10/05/11 19:22:31 GMT
FROM:    Daisuke Kuroda at OAO/NAOJ  <dikuroda@oao.nao.ac.jp>

D. Kuroda (OAO, NAOJ),  H. Hanayama, T. Miyaji, J. Watanabe(IAO, NAOJ),
K. Yanagisawa (OAO, NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:

We observed the field of GRB 100504A (Mao et al. GCNC 10712)
with the optical three color (g', Rc and Ic) CCD camera attached
to the Murikabushi 1m telescope of Ishigakijima Astronomical
Observatory.

The observation started on 2010-05-04 19:24:11 UT (~3.2 min after the
burst). We did not find any new point source within the XRT error
circle (Mao GCNC10713; Osborne et al. GCNC 10718) in all the three bands.

Three sigma upper limits of the OT are listed below. We used
GSC2.3 catalog for flux calibration.

T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.00625    19:28:41   480.0      >20.1  >20.1  >18.3
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]


GRB_name: GRB100511A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10743
SUBJECT: GRB 100511A: Super-LOTIS early observations
DATE:    10/05/11 22:18:43 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Dieter H. Hartmann (Clemson University), G. Grant
Williams (MMTO), and Peter A. Milne (Steward Observatory) report:

We observed the field of Swift trigger 421695 (Sbarufatti et al., GCN
10737) with the 0.6m Super-LOTIS telescope located at KPNO beginning 21
seconds after the trigger.  Within the BAT error circle, we detect no new
sources to a limiting magnitude of R = 17.5 (as compared to the USNO B1.0
catalog) in our first 3 minutes of stacked exposures.


GRB_name: GRB100511A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10744
SUBJECT: GRB 100511A: Fermi GBM detection/observation
DATE:    10/05/12 16:51:05 GMT
FROM:    Narayana Bhat at U Alabama/Huntsville/GBM  <Narayana.Bhat@nasa.gov>

P. N. Bhat (UAH)  
report on behalf of the Fermi GBM Team:

"At 00:49:56.23 UT on 11 May 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100511A (trigger 295231798 / 100511035).
The Fermi Observatory executed a maneuver following this trigger and
tracked the burst location for the next 5 hours, subject to
Earth-angle constraints.

The on-ground calculated location, using the GBM trigger
data, is RA = 109.29, DEC = -4.65 (J2000 degrees,
equivalent to 07 h 17.2 m, -4 d 39 '), 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 43 degrees.

The GBM light curve shows several pulses
with a duration (T90) of about 38 s (50-300 keV).
The time-averaged spectrum from T0-7.4 s to T0+52 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.32 +/- 0.02 and
the cutoff energy, parameterized as Epeak, is
946.6 (+134/-110) keV

(C-stat 1777 for 863 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(7.08 +/- 0.05)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T0+25 s in the 8-1000 keV band
is 8.81 +/- 0.18 ph/s/cm^2.

A Band function fits the spectrum equally well
(C-stat 1776 for 862 d.o.f.) with Epeak= 882.5 +166/-115 keV,
alpha = -1.3 +/- 0.02 and beta = -2.43 (+0.24/-1.71).

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


GRB_name: GRB100510A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10745
SUBJECT: GRB 100510A: Fermi GBM detection/observation
DATE:    10/05/12 18:52:10 GMT
FROM:    Narayana Bhat at U Alabama/Huntsville/GBM  <Narayana.Bhat@nasa.gov>

P. N. Bhat (UAH), Vandiver Chaplin (UAH), Valerie Connaughton (UAH)
and Chip Meegan (USRA)
report on behalf of the Fermi GBM Team:

"At 19:27:06.97 UT on 10 May 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100510 (trigger 295212428 / 100510810),
which was also detected by the MAXI/GSC (Morii et al. 2010, GCN 10739)

The on-ground calculated location, using the GBM trigger
data, is RA = 355.05, DEC = -18.86 (J2000 degrees,
equivalent to 23 h 40 m, -18 d 52 '), with an uncertainty
of 5 degrees (radius, 1-sigma containment,
statistical only; The GBM on-ground location is subject to systematic
errors due to blockage by the solar panels at this orientation.)
 
The angle from the Fermi LAT boresight is 90 degrees.

The GBM light curve consists of a single FRED
with a duration (T90) of about 31 s (50-300 keV).
The time-averaged spectrum from T0-11 s to T0+54 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.97 +/- 0.18 and
the cutoff energy, parameterized as Epeak, is 70 +/- 6.8 keV

(C-stat value 553.2 for 242 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(2.68 +/- 0.08)E-06 erg/cm^2. The 0.256-sec peak photon flux measured
starting from T0 s in the 8-1000 keV band
is 0.8 +/- 0.03 ph/s/cm^2.

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


GRB_name: GRB100513A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10746
SUBJECT: GRB 100513A: Swift detection of a burst
DATE:    10/05/13 02:23:42 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC),
N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
H. A. Krimm (CRESST/GSFC/USRA), R. Margutti (INAF-OAB),
C. B. Markwardt (CRESST/GSFC/UMD), D. M. Palmer (LANL),
B. Sbarufatti (INAF-OAB/IASFPA), M. H. Siegel (PSU),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 02:07:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100513A (trigger=421814).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 169.580, +3.605 which is 
   RA(J2000) = 11h 18m 19s
   Dec(J2000) = +03d 36' 19"
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 50 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The XRT began observing the field at 02:09:15.5 UT, 126.8 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued,
fading X-ray source with an enhanced position: RA, Dec 169.6119, 3.6272 which
is equivalent to:
   RA(J2000)  = 11h 18m 26.86s
   Dec(J2000) = +03d 37' 38.1"
with an uncertainty of 2.5 arcseconds (radius, 90% containment). This
location is 139 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.  We cannot determine whether the source is
fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
4.19e+20 cm^-2 (Kalberla et al. 2005). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 130 seconds after the BAT trigger. No credible
afterglow candidate has  been found in the initial data products. The
XRT position is outside of the 2.7'x2.7' sub-image.  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 0.05. 

Burst Advocate for this burst is W. H. Baumgartner (wayne 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: GRB100513A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10747
SUBJECT: GRB 100513A: PAIRITEL NIR afterglow candidate
DATE:    10/05/13 03:48:19 GMT
FROM:    Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>

A. N. Morgan, D. A. Perley, C. R. Klein, and J. S. Bloom (UC Berkeley) report:

We observed the location of GRB 100513A (Baumgartner et al., GCN 10746)
with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations
began at 2010-05-13 03:03:07 UT, ~0.77 hours after the Swift Trigger,
after sunset.  In  mosaics (effective exposure time of 0.92 hours)
taken simultaneously in the J, H, and Ks filters, we detect a NIR
source within the XRT error circle at a location:

11:18:26.8, +03:37:40 (J2000)

The preliminary photometry yields:

post burst
t_mid (hr) exp.(s) filt  mag   m_err
0.93       772     J     17.7  0.1

All magnitudes are given in the Vega system, calibrated to 2MASS. No
correction for Galactic extinction has been made to the above reported
values.

[GCN OPS NOTE(13may10): Per author's request, the Palmer reference
was change to the Baumgartner reference.]


GRB_name: GRB100513A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10748
SUBJECT: GRB 100513A: SARA-N Upper Limit
DATE:    10/05/13 05:26:18 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Dieter H. Hartmann (Clemson University) and Tomomi Otani
(FIT) report:

We observed the field of GRB 100513A (Baumgartner et al., GCN 10746)
beginning 1 hour and 55 minutes after the burst with the SARA-North 0.9m
telescope located at KPNO.  We do not detect the afterglow candidate
(Morgan et al., 10747) in 4 minutes of stacked exposures in each of the R
and I bands to a limiting magnitude of 19.5 in R and 19 in I (as compared
to the USNO B1.0 catalog).


GRB_name: GRB100513A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10749
SUBJECT: GRB 100513A: PAIRITEL continued observations and confirmation of  fading
DATE:    10/05/13 06:36:33 GMT
FROM:    Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>

A. N. Morgan, D. A. Perley, C. R. Klein, and J. S. Bloom (UC Berkeley) report:

We continued to observe the location of GRB 100513A (Baumgartner et al.,
GCN 10746) with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona.
The candidate afterglow (Morgan et al., GCN 10747) is detected in all
three filters (J, H, and Ks) in the first epoch.  The source fades
between epochs, confirming that this is indeed the afterglow of GRB
100513A.

The preliminary photometry yields:

post burst
t_mid (hr) exp.(s) filt  mag   m_err
0.99       1030    J     17.8  0.1
0.99       1030    H     17.2  0.1
0.99       1030    Ks    16.4  0.2

1.68       1685    J     18.0  0.1
1.68       1685    H     17.6  0.1

2.72       2855    J     18.4  0.2

All magnitudes are given in the Vega system, calibrated to 2MASS. No
correction for Galactic extinction has been made to the above reported
values.

[GCN OPS NOTE(13may10): Per author's request, the Palmer reference
was change to the Baumgartner reference.]


GRB_name: GRB100513A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10750
SUBJECT: GRB 100513A: Lick observations and R-band dropout
DATE:    10/05/13 07:03:07 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, C. R. Klein, and A. N. Morgan (UC Berkeley) report:

We began observing the location of the afterglow of GRB 100513A 
(Baumgartner et al., GCN 10746) at 04:06 UT using the Nickel 40-inch 
telescope at Lick Observatory.  A total of fourteen 300-second images 
were acquired in the R-band under clear sky conditions.

A co-add of the first 9 images (midpoint 04:35 UT) reveals a faint point 
source at the position reported by Morgan et al (GCN 10747).  The source 
is near the detection limit of the co-add and is not detected in 
individual images.

Photometry of the object relative to three nearby SDSS stars (converted 
to Rc via the Lupton transformation equation) gives the following magnitude:

R = 21.39 +/- 0.25    (t_mid = 2.46 hours)

We note that this is significantly fainter than expected from the 
preliminary JHK magnitudes of Morgan et al (GCN 10749).  The IR spectral 
index is relatively flat (beta~0.5), suggesting little host extinction. 
  Assuming no extinction in addition to the Galactic value, a direct 
power-law extrapolation of the JHK data to R-band over-predicts the 
observed flux by >2 magnitudes, strongly suggesting an R-band dropout 
and likely redshift of 4.6 < z < 6.0.  We note also that the X-ray 
column is consistent with no absorption beyond Galactic (Baumgartner et 
al.), consistent with a high-redshift origin.

We encourage I/z/Y-band follow-up to better constrain the redshift and 
dust extinction.  Spectroscopic observations are planned.


GRB_name: GRB100513A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10751
SUBJECT: GRB 100513A: Enhanced Swift-XRT position
DATE:    10/05/13 07:12:23 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 3728 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 100513A, 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 = 169.61169, +3.62774 which is equivalent
to:

RA (J2000): 11h 18m 26.81s
Dec (J2000): +03d 37' 39.9"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100513A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10752
SUBJECT: GRB 100513A: Gemini/GMOS Spectroscopic Redshift
DATE:    10/05/13 07:39:53 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, D. A. Perley, A. N. Morgan, C. R. Klein, J. S. Bloom, N. R.
Butler, and B. E. Cobb (UC Berkeley) report on behalf of a larger
collaboration:

We have obtained an optical spectrum of the afterglow (Morgan et al., GCN
10747) of GRB 100513A (Baumgartner et al., GCN 10746) with the Gemini
Multi-Object Spectrograph mounted on the 8 m Gemini North
telescope.  Observations began at 6:13 UT on 13 May (~ 4.1 hours after the
GRB) and cover the wavelength range from 6000-10000 A.

The spectrum exhibits a strong break at approximately 7000 A which we
associate with a damped Ly-alpha system at z ~ 4.8.  We identify a series
of narrow absorption features redward of Ly-alpha, including O I 1302, Si
II 1304, C II 1334, C II* 1335, Si IV 1393, 1402, Si II 1526, and C IV
1548, 1550 all at a common redshift of z = 4.772.  The presence of C II*,
along with Ly-alpha forest continuum emission blueward of 7000 A, strongly
suggest this is the redshift of the GRB host galaxy.

The presence of the Ly-alpha break at 7000 A further explains the
relatively faint R-band afterglow observed by Perley et al (GCN 10750;
also Updike et al., GCN 10748).

We wish to thank the entire Gemini staff, in particular Richard McDermid,
for the prompt execution of these observations.


GRB_name: GRB100513A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10753
SUBJECT: GRB 100513A: Swift-BAT refined analysis
DATE:    10/05/13 11:16:24 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), 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)
(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 100513A (trigger #421814)
(Baumgartner, et al., GCN Circ. 10746).  The BAT ground-calculated position is
RA, Dec = 169.606, 3.617 deg, which is 
   RA(J2000)  =  11h 18m 25.5s 
   Dec(J2000) = +03d 37' 00.4" 
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 90%.
 
The mask-weighted light curve shows multiple overlapping peaks starting
at ~T-40 sec, peaking around T_zero, and ending at ~T+60 sec with a weak
tail extending out to around T+180 sec.  T90 (15-350 keV) is 84 +- 21 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-64.1 to T+44.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.62 +- 0.14.  The fluence in the 15-150 keV band is 1.4 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.09 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. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/421814/BA/


GRB_name: GRB100513A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10754
SUBJECT: GRB 100513A: Swift XRT refined analysis
DATE:    10/05/13 14:32:45 GMT
FROM:    Vanessa Mangano at INAF-IASFPA  <vanessa@ifc.inaf.it>

V. Mangano (INAF IASF Pa), B. Sbarufatti (INAF IASF Pa, INAF OAB)
report on behalf the Swift XRT team:

We have analysed the first four orbits of XRT data of GRB 100513A
(Baumgartner et al. in GCN Circ. 10746),
consisting of 154 s exposure in Windowed Timing mode
(from T+130 s to T+284 s) and 9 ks exposure in Photon Counting
mode (from T+285 s to T+19 ks).
The UVOT-enhanced XRT position was given by Evans et al.
in GCN Circ. 10751.

After an initial flaring activity the light curve can be modelled
with a power-law decay with an index of alpha=3.3 +/- 0.15
followed by a break at 714 +/- 40 s to an alpha=0.78 +/- 0.04.

A spectrum formed from the WT[PC] mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.0+/-0.2 [2.3+/-0.2].
The best-fitting absorption column at the estimated redshift z=4.8
(Cenko et al. in GCN Circ. 10752) is 1.9 +/- 1.1 x 10^22 cm^-2,
in excess of the Galactic value of 4.2 x 10^20 cm^-2 (Kalberla et al. 
2005).
Uncertainties are given at 90% c.l.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from these spectra is 3.4 x 10^-11 (4.3 x 10^-11) erg cm^-2 
count^-1.

If the light curve continues to decay with a power-law decay index of
0.78, the count rate at T+24 hours will be 0.004 count s^-1, corresponding
to an observed (unabsorbed) 0.3-10 keV flux of 1.4 x 10^-13 (1.7 x 10^-13)
erg cm^2-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00421814.

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


GRB_name: GRB100513A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10755
SUBJECT: GRB 100513A, RIMOTS optical upper limits
DATE:    10/05/13 15:06:18 GMT
FROM:    Kazuhiro Noda at Miyazaki U  <kaz1206@astro.miyazaki-u.ac.jp>

K.Noda, N.Ohmori, A.Daikyuji, Y.Nisioka, M.Yamauchi
(University of Miyazaki)

We have observed the field covering the error circle of
GRB GRB100513A (Swift trigger 421814, GCN 10746(Baumgartner et al.), 
GCN 10746(Morgan et al.), GCN 10751(Evans et al.))
with the unfiltered CCD camera on the 30-cm telescope
at University of Miyazaki.
The observation was started 12:52:15 UT, about 10.7 hr 
after the Swift trigger time.
We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog,
There is no new source at the reported position.
(GCN 10746(Baumgartner et al.), GCN 10746(Morgan et al.), GCN 10751(Evans et al.))

the upper limits are as follows:
--------------------------------------------------------------
Start(UT)  End(UT)  Num. of frames  Limit (mag.)
--------------------------------------------------------------
12:52:15  12:52:45    1  14.05
12:52:15  13:51:11 42  16.78
---------------------------------------------------------------


GRB_name: GRB100513A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10756
SUBJECT: GRB 100513A: Swift/UVOT upper limits
DATE:    10/05/13 16:01:19 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) and W. H. Baumgartner (GSFC/UMBC) report
on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB
100513A 130s after the BAT trigger (Baumgartner et al., GCN 10746).
We do not detect any source at the enhanced Swift XRT position
(Evans et al., GCN 10751) nor at the position of the PAIRITEL NIR
detection (Morgan et al., GCN 10747).  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     130     1707    411      > 21.29
v         618     1757    136      > 19.02
b         544     1683    116      > 19.89
u         289     1658    343      > 20.22
uvw1      667     1462     97      > 19.33
uvm2     5000     5200    196      > 19.59
uvw2     6026     6226    196      > 20.03

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.05 mag
(Schlegel et al. 1998). All photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB100513A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10757
SUBJECT: GRB 100513A: Faulkes Telescope South observations
DATE:    10/05/13 16:15:41 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

C. Guidorzi (U. Ferrara) & A. Gomboc (U. Ljubljana)
report on behalf of a large collaboration:

On 2010 May 13 at 11:44:17 UT the 2-m Faulkes Telescope
South began observing the Swift GRB 100513A (Baumgartner
et al., GCN Circ. 10746) using the i' filter,
corresponding to 9.6 hr after the burst trigger time.

We clearly detect the NIR afterglow (Morgan et al.
GCN Circ. 10747, 10749) with the following magnitude:

Mid time from   Total Exp   Filter    Magnitude
trigger (hr)    (s)
-------------------------------------------------
9.89            6x300        i'       21.3 +- 0.2
-------------------------------------------------

Magnitude has been calibrated from nearby SDSS stars.


GRB_name: GRB100513A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10758
SUBJECT: GRB 100513A: Faulkes Telescope South observations
DATE:    10/05/14 15:32:58 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

C. Guidorzi (U. Ferrara) & A. Gomboc (U. Ljubljana)
report on behalf of a large collaboration:

On 2010 May 13 at 11:44:17 UT the 2-m Faulkes Telescope
South began observing the Swift GRB 100513A (Baumgartner
et al., GCN Circ. 10746) using the i' filter,
corresponding to 9.6 hr after the burst trigger time.

We clearly detect the NIR afterglow (Morgan et al.
GCN Circ. 10747, 10749) with the following magnitude:

Mid time from   Total Exp   Filter    Magnitude
trigger (hr)    (s)
-------------------------------------------------
9.89            6x300        i'       21.3 +- 0.2
-------------------------------------------------

Magnitude has been calibrated from nearby SDSS stars.


GRB_name: GRB100514A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10759
SUBJECT: GRB 100514A: Swift detection of a burst
DATE:    10/05/14 19:05:55 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

C. B. Markwardt (CRESST/GSFC/UMD), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
S. Campana (INAF-OAB), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU), C. Guidorzi (U Ferrara),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
W.B Landsman (GSFC), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL),
M. Perri (ASDC), T. Sakamoto (NASA/UMBC), M. H. Siegel (PSU),
M. Stamatikos (OSU/NASA/GSFC), M. A. Stark (PSU),
R. L. C. Starling (U Leicester), G. Stratta (ASDC),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 18:53:58 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100514A (trigger=421962).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 328.821, +29.170 which is 
   RA(J2000)  =  21h 55m 17s
   Dec(J2000) = +29d 10' 13"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a few overlapping peaks
with a duration of about 30 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The XRT began observing the field at 18:55:39.5 UT, 101.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright, fading 
uncatalogued X-ray source located at RA, Dec 328.82244, 29.15989 which
is equivalent to:
   RA(J2000)  = 21h 55m 17.39s
   Dec(J2000) = +29d 09' 35.6"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 36 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
7.74e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 4.16e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 110 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 19.6 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
0.10. 

Burst Advocate for this burst is C. B. Markwardt (Craig.Markwardt 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: GRB100514A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10760
SUBJECT: GRB 100514A: Faulkes Telescope South observations 
DATE:    10/05/14 21:58:05 GMT
FROM:    Carole Mundell at ARI, JMU,Liverpool  <cgm@astro.livjm.ac.uk>

C.G. Mundell, R.J. Smith (Liverpool JMU), C. Guidorzi (U. Ferrara), A. Gomboc 
(U. Ljubljana) report on behalf of a large collaboration:

"On 2010 May 14 at 18:57:31.55 UT the 2-m Faulkes Telescope South began 
observing Swift GRB 100514A (Markwardt  et al., GCN Circ. 10759) at
3.55 min after the GRB trigger time.

No optical afterglow is detected in R or i'-band filters to the following 
limits (relative to the USNO-B1) derived from co-added images:

   Mid time from    Filter   Limiting Magnitude
   trigger (min)
   ------------------------------------------------
   34.36   R    > 20.3
   38.55   i'    > 19.5
   ------------------------------------------------

We note that our limits seem to support a relatively high z for this burst, 
rather than a nearby extinguished afterglow,  consistent with the lack of 
additional column density in the X-ray spectrum. Further followup observations 
are encouraged."


GRB_name: GRB100514A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10761
SUBJECT: GRB 100514A: Swift-BAT refined analysis
DATE:    10/05/15 01:48:18 GMT
FROM:    Craig Markwardt at NASA/GSFC/UMD  <craigm@milkyway.gsfc.nasa.gov>

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), 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+302 sec from recent telemetry 
downlinks, we report further analysis of BAT GRB 100514A (trigger 
#421962) (Markwardt, et al., GCN Circ. 10759). The BAT ground-calculated 
position is RA, Dec = 328.757, 29.175 deg, which is
    RA(J2000)  =  21h 55m 01.7s
    Dec(J2000) = +29d 10' 29.8"
with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment). 
The partial coding was 76%.

The mask-weighted light curve shows FRED-like peak starting at ~T-2 sec, 
peaking at ~T+7 sec, and ending at ~T+38 sec.  T90 (15-350 keV) is 26.2 
+- 8.2 sec (estimated error including systematics).

The time-averaged spectrum from T+0.3 to T+30.8 sec is best fit by a 
simple power-law model.  The power law index of the time-averaged 
spectrum is 1.97 +- 0.25.  The fluence in the 15-150 keV band is 4.0 +- 
0.7 x 10-7 erg/cm2.  The 1-sec peak photon flux measured from T+6.23 sec 
in the 15-150 keV band is 0.6 +- 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/421962/BA/


GRB_name: GRB100514A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10762
SUBJECT: GRB 100514A: Enhanced Swift-XRT position
DATE:    10/05/15 03:19:02 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 1720 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 100514A, 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 = 328.82257, +29.16001 which is equivalent
to:

RA (J2000): 21h 55m 17.42s
Dec (J2000): +29d 09' 36.0"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100514A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10763
SUBJECT: GRB 100514A: MASTER-Net  optical  observations 
DATE:    10/05/15 07:20:45 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

V.Krushinski, I.Zalozhnih, T.Kopytova, A.Popov
Ural State University, Kourovka

E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina,
D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, 
D.Zimnukhov, M. Kornilov, A.Sankovich
Sternberg Astronomical Institute, Moscow State University

K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, 
O.Chuvalaev
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, A.Garusina Blagoveschensk Educational State 
University, Blagoveschensk



A. Tlatov, A.V. Parkhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory



MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located at Kourovka Observatory  (Ural)    was responted to the 
GRB 100514A (Swift Bat alert, Markwardt et al, GCN CIRC 10759)   25 sec 
after Notice time  and 71 s after the GRB time.

There is no OT on the first 20-s  exposition time unfiltered images inside 
Swift XRT error box (Goad et al., GCN CIRC 10762)
brighter 17.0.




The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB100514A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10764
SUBJECT: GRB 100514A: Swift XRT refined analysis
DATE:    10/05/15 09:49:49 GMT
FROM:    Giulia Stratta at ASDC  <giulia.stratta@gmail.com>

G. Stratta (ASDC), V. D'Elia (ASDC) and C. B. Markwardt (CRESST/GSFC/UMD)
report on behalf of the Swift-XRT team:

We have analysed 24.9 ks of XRT data for GRB 100514A (Markwardt et al. GCN
Circ. 10759), from 91 s to 25.0 ks after the BAT trigger. The data comprise
82 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was
slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT
position for this burst was given by Goad et al. (GCN. Circ 10762).

The light curve can be modelled with a broken power-law decay with decay
indices of alpha_1 = 5.15 +/- 0.15, alpha_2 = 0.55 +/- 0.20 and a break
at t = 560+/-60 sec after the trigger.

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 3.96 (+0.18, -0.17). The
best-fitting absorption column is 2.9 (+/-0.3) x 10^21 cm^-2, in excess of
the Galactic value of 7.7 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 2.1 x 10^-11 (2.0 x 10^-10) erg cm^-2 count^-1. The spectrum
softens in the PC mode data to a photon spectral index of 2.74 (+0.46,
-0.44) with a best-fitting column of 5.4 (+6.5, -2.9) x 10^20 cm^-2 in
excess
of the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum is now 2.9 x 10^-11 (5.5 x
10^-11) erg cm^-2 count^-1.

Uncertainties are given at 90% confidence level.

If the light curve continues to decay with a power-law decay index of 0.55,
the count rate at T+24 hours will be 1.8 x 10^-3 count s^-1, corresponding
to an observed (unabsorbed) 0.3-10 keV flux of 5.2 x 10^-14 (9.9 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/00421962.

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


GRB_name: GRB100514A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10765
SUBJECT: GRB 100514A: YNAO-GMG observations
DATE:    10/05/15 15:04:17 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao (YNAO & INAF-OAB) and J. Bai (YNAO) report on behalf of the GMG group:
 
Starting from 19h 49m 49s UT, after about 1 hour of the GRB trigger, we observed the field of GRB 100514A (Markwardt et al. GCN 10759) with one 2.4-m telescope located at Gao-Mei-Gu (GMG). We did not find any optical afterglows in a series of R-band images. The magnitude limit(relative to USNO-B1) is about 20.6.
 
This message might be cited. 


GRB_name: GRB100514A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10766
SUBJECT: GRB 100514A: Swift/UVOT Observations
DATE:    10/05/15 16:12:01 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F.E. Marshall (NASA/GSFC) and C.B. Markwardt (CRESST/GSFC/UMD)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100514A
110 s after the BAT trigger (Markwardt et al., GCN Circ. 10759).
There is a marginal (2.6-sigma) detection of a possible optical
afterglow at the enhanced XRT position
(M.R. Goad et al., GCN Circ. 10762) in the first white finding chart.
There is no detection in any of the other initial UVOT exposures.
Preliminary results (3-sigma upper limits or values with 1-sigma uncertainties) 
using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the finding chart (FC)
exposures and summed subsequent exposures are:

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

white_FC           110          260          147         21.1 +/- 0.3
u_FC               268          518          246         >20.2
white              549         7708          516         >21.0
v                  600         6843          529         >20.0
b                  524         7666          529         >20.5
u                  268         7459          775         >20.5
w1                 650         7254          529         >21.0
m2                 624         7048          529         >20.2
w2                 574         6639          352         >19.9

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.10 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100514A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10767
SUBJECT: GRB 100514A: optical afterglow confirmation
DATE:    10/05/16 21:42:21 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of the Swift GRB 100514A (Markwardt  et al. GCN 10759) 
with Shajn telescope of CrAO between (UT) May 15  00:04:38 and  15T01:10:33 
under good weather conditions and mean seeing of  2 arcsec. Inside the 
enhanced XRT error circle (Goad et al. GCN 10762) we detect the object with 
coordinates

RA(J2000):  21 55 17.46
Dec(J2000): +29 09 36.13

with uncertainties of 0.3" in each coordinates.

The photometry of the object based on USNO-B1.0 star 1191-0563318  (J2000) 
RA= 21:55:19.80 Dec= +29:10:10.0  (assuming  R2=19.25)  is following:

T0+      Filter,   Exposure, mag.
(mid, d)              (s)

0.2390   R       57x60     23.2 +/- 0.2

The afterglow candidate reported by Marshall and  Markwardt (GCN 10766) is 
fading by ~2 mag. within 5.7 hours, and hence we confirm the afterglow.


GRB_name: GRB100513A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10768
SUBJECT: GRB 100513A: EVLA radio observation
DATE:    10/05/16 22:59:55 GMT
FROM:    Poonam Chandra at Royal Mil. College Canada  <Poonam.Chandra@rmc.ca>

Poonam Chandra (RMC) and Dale A=2E Frail (NRAO) report on behalf of a
larger collaboration:

We observed GRB 100513A (Baumgartner et al. GCN 10746) with the
Expanded Very Large Array (EVLA) on May 14.02 UT at a center frequency
of 8.46 GHz.  We do not detect any radio source anywhere within the
refined XRT error circle (Evans et al., GCN 10751) to a 3-sigma limit
of 60 uJy.  The peak flux at the PAIRITEL afterglow position (Morgan et al.,
GCN 10747) is -43+/-20 uJy.


The EVLA is still undergoing active commissioning and we caution that
these results should be considered preliminary=2E The National Radio
Astronomy Observatory is a facility of the National Science Foundation
operated under cooperative agreement by Associated Universities=2C Inc.


GRB_name: GRB100517A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10769
SUBJECT: GRB 100517A: MASTER-Net wide field camera  prompt optical  observations
DATE:    10/05/17 14:05:48 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, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, 
M. Kornilov, A.Sankovich, V.Sennik
Sternberg Astronomical Institute, Moscow State University

V.Yurkov, Yu.Sergienko, D.Varda, A.Garusina Blagoveschensk Educational 
State
University, Blagoveschensk

K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, O.Chuvalaev
Irkutsk State University

A. Tlatov, A.V. Parkhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory

V.Krushinski, I.Zalozhnih, T.Kopytova, A.Popov
Ural State University, Kourovka

MASTER Very Wide Field Cameras located at Blagoveschensk (D=50 mm, 1000 
square degrees, 11 Mpx, 36" per pix) has observed  FERMI error box (FERMI 
trigger N295791986 ra=161.933 dec=+38.317) with 1s exposure befoure, 
during and after GRB time without time gap between images. This camera is 
on one mount with is more large MASTER telescope. These observation have 
been received during the regular  sky survey. Directly at the moment of 
GRB the telescope had repointing, so sets since 3 seconds before grb to 3 sec. after grb time (2010-05-17 12:26:24 UT) is moved.

The magnitude limit of the each good image is  ~ 8-m at the center of FOW, 
and ~ 4-5 m on each moved image.

Our unfiltered images are calibrated relative to Tycho stars (V).

Specification of coordinates is required.

Images available here:
http://observ.pereplet.ru/images/GRB100517A/after.jpeg
http://observ.pereplet.ru/images/GRB100517A/before.jpeg

The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB100518A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10772
SUBJECT: GRB 100518A: a long GRB detected with INTEGRAL
DATE:    10/05/18 12:32:27 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

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

a long gamma ray burst has been detected by IBAS in the IBIS/ISGRI data at 
11:33:35 U.T. on May 18th. It has a FRED light curve lasting about 30 s. 
Its refined coordinates (J2000) are:

R.A.:     304.7999 [deg]
DEC.:    -24.5609  [deg]

with an uncertainty of 1.6 arcmin (90% c.l.).

A preliminary analysis gives a peak flux in the 20-200 keV range of about 
0.5 ph/cmsq/s (1 s integration time) and a fluence over the same energy 
range of about 5 10e-7 erg/cmsq.

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: GRB100513A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10774
SUBJECT: GRB 100513A: MITSuME Akeno Optical Observation
DATE:    10/05/18 13:50:13 GMT
FROM:    Yoichi Yatsu at Tokyo Tech.  <yatsu@hp.phys.titech.ac.jp>

Y.Yatsu, H. Nakajima, T. Enomoto, K. Kawakami,
K. Tokoyoda, Shimokawabe, and N. Kawai (Tokyo Tech)
 report on behalf of the MITSuME collaboration:

We observed the field of GRB100513A (Baumgartner et al. GCNC 10746)
with the three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50 cm optical telescope at Akeno, Japan.

The observation started at 2010-05-13 11:07:42 UT.
On the combined images, we could not find the optical counterpart
 in the XRT error circle (GCN 10746) in the three bands.
The 3-sigma upper limits based on the GSC2.3 catalog are listed below:

Start(UT) -- END(UT)  Total EXP[sec]    g'     Rc     Ic
----------------------------------------------------------------
11:07:42.1 -- 11:32:45.1   540.0      >18.9  >18.8  >18.3
14:23:16.8 -- 14:50:38.0   960.0      >17.8  >18.0  >17.4
14:50:46.5 -- 15:36:25.0  2220.0     > 19.1 > 19.0 > 18.4
----------------------------------------------------------------


GRB_name: GRB100518A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10775
SUBJECT: GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
DATE:    10/05/18 14:35:35 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. Stamatikos (OSU/NASA/GSFC), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), M. M. Chester (PSU),
P. A. Evans (U Leicester), J. M. Gelbord (PSU), J. A. Kennea (PSU),
C. Pagani (U Leicester), J. L. Racusin (NASA/GSFC) and L. Vetere (PSU)
report on behalf of the Swift Team:

Swift began a target of opportunity observation of GRB 100518A on May
18, 2010 at 14:10 UT, approximately 2.6 hours after the burst was
detected by INTEGRAL. Swift data for these observations utilize Target
ID 20138. 

The XRT began observing the field at 14:12:42.5 UT, 9.5 ks after the
INTEGRAL trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 304.78875, -24.55459 which
is equivalent to:
   RA(J2000)  = 20h 19m 9.30s
   Dec(J2000) = -24d 33' 16.5"
with an uncertainty of 4.1 arcseconds (radius, 90% containment). This
location is 42 arcseconds from the INTEGRAL position, within the
INTEGRAL error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper.  We cannot determine whether the source is
fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
6.4e+20 cm^-2 (Kalberla et al. 2005). 

UVOT took a finding chart exposure of 150 seconds with the White  
filter starting 9551 seconds after the INTEGRAL 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  19.6  mag. The 8'x8' region for 
the list of sources generated on-board is typically  complete to about
18  mag.  No correction has been made for the  expected extinction
corresponding  to  E(B-V) of 0.07. 

Burst Advocate for this burst is M. Stamatikos (Michael.Stamatikos-1 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: GRB100518A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10776
SUBJECT: GRB 100518A: Faulkes Telescope North Afterglow Candidate
DATE:    10/05/18 15:00:48 GMT
FROM:    Zach Cano at ARI/John Moores Liverpool  <zec@astro.livjm.ac.uk>

Z. Cano (Liverpool JMU), A. Gomboc (U. Ljubljana), C. Guidorzi (U.
Ferrara) report on behalf of a larger collaboration:

On 2010 May 18 at 11:37:46 UT the 2-m Faulkes Telescope North
automatically began observing the INTEGRAL GRB 100518A (Mereghetti et al.,
GCN 10772).

The LT-TRAP automatically detected a fading object in R and i at the
following position:

Ra:   20:19:09.33
Dec: -24:33:16.50 (J2000)

This lies 0.4 arcseconds from the XRT centroid (Stamatikos et al., GCN
10775).


GRB_name: GRB100518A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10778
SUBJECT: GRB 100518A: BOOTES-3 optical observations
DATE:    10/05/19 08:44:42 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (INAF-OAB),  A.J. Castro-Tirado, J. Gorosabel,
M. Jelinek (IAA-CSIC), P. Kubanek (IPL UV, IAA-CSIC),
R. Cunniffe, S. Guziy (IAA-CSIC), P. Yock  (Auckland Univ.),
W.H. Allen (Vintage  Lane Obs.), I. Bond (Massey Univ.), G. Christie
(Stardome Obs.) report on behalf of a larger collaboration:

"We have observed the field of the INTEGRAL GRB 100518A
(Mereghetti et al., GCN 10772) using the 0.6m Yock-Allen robotic
telescope (BOOTES-3) located in Blenheim, New Zealand.
Preliminary analysis of a combined 40x60s unfiltered exposure
taken (mid-epoch) on 18th May 2010, 14:01 UT (2.47 hours after
the burst, when acceptable weather allowed to perform the
observations) does not show any source at the position of the
optical afterglow candidate (Cano et al., GCN 10776) down to a
3-sigma limiting magnitude of R ~ 20.7 using USNO-B1.0 as
photometric reference."


GRB_name: GRB100518A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10779
SUBJECT: GRB 100518A: optical afterglow decay
DATE:    10/05/19 09:04:53 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

D. Kopac (U. Ljubljana), C. Guidorzi (U. Ferrara), Z. Cano (Liverpool JMU),
A. Gomboc (U. Ljubljana), report on behalf of a larger collaboration:

The 2-m Faulkes Telescope North observed the optical afterglow of
GRB 100518A (Cano et al. GCN Circ. 10776) from 4.2 min to 3.7 hours from
the INTEGRAL trigger time (Mereghetti et al. GCN Circ. 10772) in
the BVRi filters.
Within this time interval the afterglow is observed to decay in both
R and i filters with an average power-law decay slope of 0.7 +/- 0.1,
with the following initial magnitudes:

Mid time from   Total Exp   Filter    Magnitude
trigger (min)    (s)
-------------------------------------------------
4.9             3x10        R         19.4 +- 0.1
9.8             10          i         18.8 +- 0.2
-------------------------------------------------

Magnitudes have been calibrated from nearby USNOB-1 stars.


GRB_name: GRB100518A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10780
SUBJECT: GRB 100518A: Swift-XRT refined analysis
DATE:    10/05/19 09:13:34 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A. P. Beardmore, R. L. C. Starling, P. A. Evans (U. Leicester) and
M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift-XRT team:

We have analysed 4.7 ks of XRT data for the INTEGRAL triggered GRB
100518A (Mereghetti et al. GCN Circ. 10772, Stamatikos et al.  GCN
Circ. 10775), from 9.6 ks to 17.9 ks after the BAT trigger. The data
are entirely in Photon Counting (PC) mode.  Using 2.4 ks of PC mode
data and 3 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 = 304.78931, -24.55436 which is
equivalent to:

RA (J2000): 20h 19m 9.43s
Dec (J2000): -24d 33' 15.7"

with an uncertainty of 2.2 arcsec (radius, 90% confidence). Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and
Evans et al. (2009, MNRAS, 397, 1177).

The light curve can be modelled with  a power-law decay with a decay
index of alpha=0.68 +1.00 -0.96.

A spectrum formed from the entire PC mode dataset can be fitted with
an absorbed power-law with a photon spectral index of 3.6 +1.4 -0.7.
The best-fitting absorption column is (4.5 +3.5 -3.3) x 10^21 cm^-2,
in excess of the Galactic value of 6.4 x 10^20 cm^-2 in the direction
of the burst (Kalberla et al.  2005). The observed (unabsorbed) 0.3-10
keV flux for this spectrum is 6.1 x 10^-13 (5.4 x 10^-12) erg cm^-2
s^-1, resulting in a counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor of 2.7 x 10^-11 (2.4 x 10^-10) erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020138.

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


GRB_name: GRB100518A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10781
SUBJECT: GRB 100518A: Swift/UVOT Upper Limits
DATE:    10/05/19 11:00:50 GMT
FROM:    Peter Curran at MSSL  <pac@mssl.ucl.ac.uk>

P.A. Curran (MSSL-UCL)  and M. Stamatikos (OSU/NASA/GSFC) report on
behalf of the Swift/UVOT team:

During Swift target of opportunity observations of GRB 100518A 
(Stamatikos et al. GCN Circ. 10775),  Swift/UVOT began settled 
observations starting 9551 seconds after the INTEGRAL trigger 
(Mereghetti et al. GCN Circ. 10772). No optical afterglow consistent 
with the enhanced XRT position (Beardmore et al. GCN Circ. 10780) or the 
optical counterpart (Cano et al. GCN Circ. 10776) is  detected in the 
UVOT exposures. Preliminary 3-sigma upper limits using the UVOT 
photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first 
finding chart (FC) exposure and subsequent exposures are:

Filter   T_start(s)   T_stop(s)   Exp(s)   Mag
------------------------------------------------
white    9551         9701        147      >21.4 (FC)
white    9551         11529       1033     >22.4
v        16324        17231       885      >20.7
b        9711         10618       885      >21.7
m2       17236        17899       652      >20.9
w2       11536        16318       1137     >21.6


The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.07 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100518A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10782
SUBJECT: GRB 100518A: GROND afterglow observation and photo-z
DATE:    10/05/19 15:28:57 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

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

We observed the field of GRB 100518A (Mereghetti et al., GCN 10772) 
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 
405) mounted at the 2.2 m MPI/ESO telescope at La Silla Observatory (Chile).

Observations started at 09:12 UT on May 19, 21.7 hours after the GRB 
trigger, and continued for 1 hour.

In stacked images of 50 min total integration time in g'r'i'z' we detect 
the optical afterglow (Cano et al., GCN 10776) in r'i' and z'.

Preliminary photometry yields the following AB magnitudes and upper limits:

g' > 25.3
r' = 23.8 +- 0.1
i' = 23.6 +- 0.2
z' = 23.5 +- 0.2

calibrated against the GROND zeropoints and 2MASS field stars. After 
correcting for the foreground reddening of E(B-V)=0.07 (Schlegel et al. 
1998) and assuming no intrinsic extinction, a fit with Hyper-z 
(Bolzonella et al. 2000) results in a preliminary photometric redshift 
of z = 4.0+0.3-0.5.


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10783
SUBJECT: GRB 100418A: CrAO optical observations
DATE:    10/05/19 19:25:13 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of the Swift GRB 100418A (Marshall  et al. GCN 10612) 
with Shajn telescope of  CrAO between (UT) May, 14  21:07 -- 22:48 under 
photometric weather conditions and mean seeing of about 2 arcsec.
The preliminary photometry of the afterglow+host in a stacked image based on 
USNO-B1.0 star 1014-0271368  (RA(J2000) = 17:05:26.42 Dec(J2000)= 
+11:27:32.9)  assuming  R=17.32  is following:

T0+      Filter,   Exposure,  mag.
(mid, d)              (s)

26.0332     R       90x60    21.86 +/-0.06

The photometry is compatible with R-magnitude reported by Perley et al, GCN 
10727 (R=21.85+/-0.05 at 17.739 days) and still brighter than assumed 
R-magnitude of the normal type of host galaxy (SDSS based ugriz-> R 
conversion) which cannot be explained solely by afterglow contribution 
fading steeper than power law with decay index of  .~0.8. 


GRB_name: GRB100522A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10784
SUBJECT: GRB 100522A: Swift detection of a burst
DATE:    10/05/22 04:14:56 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

E. Troja (NASA/GSFC/ORAU), A. P. Beardmore (U Leicester),
M. M. Chester (PSU), J. M. Gelbord (PSU),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), C. Pagani (U Leicester),
D. M. Palmer (LANL), R. L. C. Starling (U Leicester),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 03:45:52 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100522A (trigger=422783).  Swift slewed immediately to 
the burst.  The BAT on-board calculated location is 
RA, Dec 6.983, +9.417 which is 
   RA(J2000) = 00h 27m 56s
   Dec(J2000) = +09d 25' 03"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a first pair of peaks near T0 with a duration of 
about 5 sec and a second fainter and softer pair of peaks near T+30 s.  
The peak count rate was ~15,000 counts/sec (15-350 keV), at ~0 sec 
after the trigger. 

The XRT began observing the field at 03:46:57.7 UT, 65.4 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
6.9867, 9.4023 which is equivalent to:
   RA(J2000)  = 00h 27m 56.82s
   Dec(J2000) = +09d 24' 08.1"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 54 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 (3.98e+20
cm^-2, Kalberla et al. 2005), with an excess column of 2.7
(+2.46/-2.10) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 2.40e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 73 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 XRT position is 18.5 mag. No  correction has been
made for the expected extinction corresponding to E(B-V) of  0.06. 

Burst Advocate for this burst is E. Troja (eleonora.troja 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: GRB100522A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10785
SUBJECT: GRB 100522A: BOOTES-2 optical limit
DATE:    10/05/22 05:24:50 GMT
FROM:    Martin Jelinek at Inst.Astrophys.Andalucia,Granada  <mates@iaa.es>

M. Jelnek (IAA-CSIC Granada), P. Kubnek (IPL Valencia, IAA-CSIC) and 
A. J. Castro-Tirado (IAA-CSIC), on behalf of a larger collaboration,

report:

"The 0.6m TELMA robotic telescope at the BOOTES-2 astronomical
station in Mlaga (Spain) reacted to the Swift GRB 100522A
(Troja et al., GCNC10784), starting 10m25s after the trigger
(15s after receiving the delayed trigger). A set of 10s
unfiltered images was obtained, however the progressing
twillight degraded the images (already taken at high airmass).
The 120s coadded image with an exposure mean time 735s after
the GRB provides a limit R>15.5 at the XRT position reported
by Troja et al."

This message can be quoted.


GRB_name: GRB100522A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10786
SUBJECT: GRB 100522A: NIR observations from CAHA
DATE:    10/05/22 06:14:40 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (OAB-INAF), A.J. Castro-Tirado (IAA-CSIC),
A. Guijarro and M. Alises (CAHA) report on behalf of a larger
collaboration:

"We have observed the field of GRB 100522A (Troja et al. GCNC
10784) with the 3.5m CAHA telescope (+Omega2000) in J and Ks
bands. The observations were obtained during twilight, with a
very high background. In a preliminary analysis we do not detect
any source within the XRT error circle in any of the images. The
3x60s combined J-band exposure, has a mean time  04:20:27 UT
and a 3-sigma limiting magnitude of 17.9. The 4x60s combined
K-band exposure has a mean time of 04:31:50 and a limiting
magnitude of 16.3."


GRB_name: GRB100522A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10787
SUBJECT: GRB 100522A: Enhanced Swift-XRT position
DATE:    10/05/22 12:42:18 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 3778 s of XRT Photon Counting mode data and 6 UVOT
images for GRB 100522A, 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 = 6.98662, +9.40184 which is equivalent
to:

RA (J2000): 00h 27m 56.79s
Dec (J2000): +09d 24' 06.6"

with an uncertainty of 1.5 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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100522A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10788
SUBJECT: GRB 100522A, Swift-BAT refined analysis
DATE:    10/05/22 13:31:13 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm@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),
E. Troja (NASA/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 the recent telemetry 
downlink,
we report further analysis of BAT GRB 100522A (trigger #422783)
(Troja, et al., GCN Circ. 10784).  The BAT ground-calculated position is
RA, Dec = 6.990, +9.397 deg which is
   RA(J2000)  =  00h 27m 57.6s
   Dec(J2000) = +09d 23' 50.1"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 71%.

The mask-weighted light curve shows a complex structure.  There are two 
main
episodes of emission, starting at T-0.5 sec and T+25 sec, respectively.  
The
first episode starts with a broad multi-peaked structure 2.5 sec long 
followed
by three short (~0.3 sec long) peaks.  Then the emission returns to
background levels before rising in a second, less intense and softer two 
peak
structure approximately 15 sec long. T90 (15-350 keV) is 35.3 +- 1.8 sec
(estimated error including systematics).

The time-averaged spectrum from T-0.5 to T+40.2 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.89 +- 0.08.  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+0.04 sec in the 15-150 keV band
is 7.1 +- 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/422783/BA/


GRB_name: GRB100522A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10789
SUBJECT: GRB 100522A: Swift XRT refined analysis
DATE:    10/05/22 13:50:22 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C. Starling, A.P. Beardmore (U. Leicester) and E. Troja (NASA/GSFC/ORAU) 
report on behalf of the Swift-XRT team:

We have analysed 5.4 ks of XRT data for GRB 100522A (Troja et al. GCN 
Circ. 10784), from 56 s to 13.6 ks after the BAT trigger. The data 
comprise 87 s in Windowed Timing (WT) mode (the first 7 s were taken while 
Swift was slewing) with the remainder in Photon Counting (PC) mode. The 
enhanced XRT position for this burst was given by Osborne et al. (GCN. 
Circ 10787).

The light curve can be modelled with a series of power-law decays. The 
initial decay index is alpha = 4.8 (+/-0.4). At T+130 s the decay flattens 
to an alpha of 0.53 (+0.04, -0.09) before breaking again at T+7830 s to a 
final decay with index alpha = 1.2 (+2.8, -0.4).

A spectrum formed from the WT mode data can be fitted with an absorbed 
power-law with a photon spectral index of Gamma = 2.82 (+0.32, -0.28). The 
best-fitting absorption column is 4.0 (+0.8, -0.7) x 10^21 cm^-2, in 
excess of the Galactic value of 4.0 x 10^20 cm^-2 (Kalberla et al. 2005). 
The PC mode spectrum has a photon index of 2.14 (+0.30, -0.28) and a 
best-fitting absorption column of 4.0 (+1.2, -1.0) x 10^21 cm^-2. The 
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced 
from this spectrum is 4.4 x 10^-11 (8.1 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 1.2, 
the count rate at T+24 hours will be 0.011 count s^-1, corresponding to an 
observed (unabsorbed) 0.3-10 keV flux of 4.8 x 10^-13 (8.9 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/00422783.

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


GRB_name: GRB100522A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10790
SUBJECT: GRB 100522A: Fermi GBM observation
DATE:    10/05/22 17:12:54 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

S. McBreen (UCD/MPE)
reports on behalf of the Fermi GBM Team:

"At 03:45:52.29 UT on 22 May 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100522A (trigger 296192754 / 100522157)
which was also detected by the Swift-BAT (Troja et al. 2010, GCN 10784).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 81 degrees.

The GBM light curve consists of two of pulses with
substructure from T0 to T0+5 s followed by two softer pulses
lasting from T0+25 s to about T0+40 sec.  The burst
has a duration (T90) of about 35.0 +/-1.5 s (50-300 keV).
The time-averaged spectrum from T0-0.003 s to T0+40.385 s is
adequately fit by a simple power law function
with index -1.81 (+/-0.03)(CSTAT 544 for 481 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(5.2 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.25 s in the 8-1000 keV band
is 11.0 +/- 0.3 ph/s/cm^2.

A power law function with an exponential high energy cutoff
fits the spectrum equally well (CSTAT 538 for 480 d.o.f).
The power law index is -1.62 (+0.10/-0.09) and
the cutoff energy, parameterized as Epeak, is 138 (+82/-32) keV.

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


GRB_name: GRB100522A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10791
SUBJECT: Swift/UVOT observations of GRB100522A.
DATE:    10/05/22 23:38:54 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

M. De Pasquale (MSS-UCL) and Eleonora Troja (NASA/GSFC/ORAU)
report on behalf of the Swift/UVOT team:

Swift/UVOT began settled observations of GRB100522A (Troja et al.
GCN Circ. 10784) starting 73 seconds after trigger. No optical afterglow
within the enhanced XRT position (Osborne et al. GCN Circ. 10787) is
detected in the UVOT exposures. Preliminary 3-sigma upper limits using
the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for
the first finding chart (FC) exposure and subsequent summed exposures are:

Filter   T_start(s)  T_stop(s)   Exp(s)   Mag
-----------------------------------------------------------
white       73         223         147      >20.1 (FC)
white       73        7223         569      >20.9
v          614        6199         352      >19.0
b          541        7018         352      >19.9
u          285       13630        1243      >20.1
uw1        663       12939        1242      >20.5
m2         639        7838         549      >20.2
w2         590        7429         363      >20.1


The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.06 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100522A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10793
SUBJECT: GRB 100522A: GROND observations, upper limits
DATE:    10/05/23 16:03:15 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

P. Afonso (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), the 7-channel imager mounted 
at the 2.2m ESO/MPI telescope on La Silla, started follow-up observations 
of the Swift/Fermi burst GRB 100522A (Troja et al. 2010, GCN 10784; 
McBreen 2010, GCN 10790) on May 23 at 09:18 UT (about 29.5 hrs after the 
burst), and continued for about 1 hour.

Within the enhanced XRT 1.5 arcsec error circle reported by Osborne et al. 
(GCN 10787) we do not find any afterglow candidate. Based on 50 min of 
total exposures in g'r'i'z' and 40 min in JHK, preliminary measured upper 
limits are (in the AB system, 3 sigma):

g' > 24.8,
r' > 24.4,
i' > 23.6,
z' > 23.3,
J  > 21.7,
H  > 20.9,
K  > 20.6,

using GROND zeropoints and the 2MASS catalog.


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10794
SUBJECT: GRB 100418A: Subaru late-time optical imaging and spectroscopy
DATE:    10/05/24 05:38:17 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

T. Hattori and  K. Aoki (Subaru Telescope)
report on behalf of the Subaru GRB team:

We observed the field of GRB 100418A (Marshall et al. GCN 10612) with FOCAS
on Subaru Telescope under an excellent condition (seeing 0.3"-0.4"),
starting at 12:13 UT on May 14 2010, 25.63 days after the trigger.
Single exposure of 120 seconds in each V, Rc, and Ic bands was acquired.
We detected and resolved the host galaxy (Malesani GCN 10621), but could not
find any point source in the galaxy.  The host galaxy magnitudes (Vega
system) are V=22.62 +-0.06, Rc=21.90 +-0.03 and Ic=21.34 +-0.05.
Rc-band magnitude is consistent with the values reported in GCN 10727
(R=21.85 +-0.05 at 17.7 days after) and GCN 10783 (R=21.86 +-0.06 at 26.0
days after).
No time variation of R-band magnitude was thus detected during 17.7 days and
26.0 days.

We also performed optical spectroscopy for the host galaxy starting
12:35 UT May 14.
We used two settings of the spectrograph with 0.8" width slit.
One was covering the wavelengths between 3900 A and 8300 A, and the other
between 5800 A and 1 micron.
The integration time of the each setting was 1 hour (1200 seconds x 3).
We found strong emission-lines such as [O II], Hgamma, Hbeta, [O III]
at z=0.624 which are same as reported in GCN 10620 and GCN 10624.
The continuum of the galaxy is very similar to that of the nearby blue
compact dwarf galaxy NGC 1140.
We could not identify any supernova feature like broad emission-lines
and bumps.


GRB_name: GRB100522A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10795
SUBJECT: GRB100522A: Suzaku WAM observation of the prompt emission
DATE:    10/05/25 03:31:22 GMT
FROM:    Arata Daikyuji at Miyazaki U  <daikyu524@astro.miyazaki-u.ac.jp>

A. Daikyuji, N. Ohmori, Y. Nishioka, M. Yamauchi (Univ. of Miyazaki),
K. Yamaoka (Aoyama Gakuin U.), S. Sugita (Nagoya U.),
Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.),
Y. Terada, M. Tashiro, W. Iwakiri, K. Takahara, T. Yasuda (Saitama U.),
M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. E. Nakagawa, T. Tamagawa (RIKEN), N. Vasquez (Tokyo Tech.), Y. Urata,
H. M. Lin (NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo),
S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:

The long GRB100522A (Swift/BAT trigger #422783 ; Troja et al., GCN 10784)
was detected by the the Suzaku Wide-band All-sky Monitor (WAM) which
covers an energy range of 50 keV - 5 MeV at 2010-05-22 03:45:52 UT (=T0).

The observed light curve shows a single peak starting at T0, ending
at T0+4s with a duration (T90) of about 3 seconds.
The WAM detected only the first bright peak observed by
Swift/BAT (Barthelmy et al., GCN 10788) and Fermi/GBM(McBreen et al.,
GCN 10790).
The fluence in 100 - 1000 keV was 1.39 (-0.18, +0.15) x10-6 erg/cm2.
The 1-s peak flux measured from T0+1s was 1.50 (-0.27, +0.24)
photons/cm2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0 to
T0+4s is well fitted by a single power-law with a photon index
of 2.26 (-0.18, +0.21) (chi2/d.o.f = 26.8/35).

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: GRB100522A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10796
SUBJECT: Konus-Wind observation of GRB 100522A
DATE:    10/05/25 12:21:36 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100522A (Swift-BAT trigger=422783;
Troja et al., GCN 10784; Barthelmy et al., GCN 10788)
triggered Konus-Wind at T0=13549.843s UT (03:45:49.843)

The burst light curve shows a single pulse
with a total duration of ~6 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100522_T13549/

As observed by Konus-Wind the burst
had a fluence of 1.7(-0.5, +0.3)x10-6 erg/cm2,
and a 256-ms peak flux measured from T0-0.256s
of 0.7(-0.2, +0.1)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+8.848 s)
is best fit in the 20 keV - 2 MeV range by a single power-law
model with a photon index of 2.9 (-/+0.5), chi2 = 78/69 dof.

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


GRB_name: GRB100526A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10797
SUBJECT: GRB 100526A: Swift detection of a burst
DATE:    10/05/26 16:36:06 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

L. Vetere (PSU), S. Campana (INAF-OAB), J. R. Cummings (NASA/UMBC),
J. M. Gelbord (PSU), D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), W.B Landsman (GSFC), J. Mao (INAF-OAB),
F. E. Marshall (NASA/GSFC), J. P. Osborne (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL), T. A. Pritchard (PSU),
B. Sbarufatti (INAF-OAB/IASFPA), M. H. Siegel (PSU), M. A. Stark (PSU)
and E. Troja (NASA/GSFC/ORAU) report on behalf of the Swift Team:

At 16:26:10 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100526A (trigger=423181).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 230.785, +25.639 which is 
   RA(J2000) = 15h 23m 08s
   Dec(J2000) = +25d 38' 20"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is usual for an image trigger, there is
no obvious variation in the immediately-available lightcurve. 

The XRT began observing the field at 16:28:36.0 UT, 145.8 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 230.7684, +25.6310 which is equivalent to:
   RA(J2000)  = 15h 23m 04.41s
   Dec(J2000) = +25d 37' 51.6"
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This
location is 61 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 2.5 s image was 2.71e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 151 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 19.6 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
0.04. 

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: GRB100526A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10798
SUBJECT: GRB 100526A: MASTER-Net  optical alert observations
DATE:    10/05/26 19:02:59 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

V.Yurkov, Yu.Sergienko, D.Varda, A.Garusina Blagoveschensk Educational State 
University, Blagoveschensk

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

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

V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, 
Kourovka

K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok
Irkutsk State University

MASTER  robotic telescope (MASTER-Net: http://observ.pereplet.ru, 200 mm, 
FOV=8 square degrees (testing mode)) and  Very Wide Field Camera (D=50 
mm, 1000 square  degrees, 11 Mpx, 36" per pix, mounted on telescope) 
located at Blagoveschensk   was ponted to the  GRB 100526A (L. Vetere et 
al. gcn 10797) 21 min after burst. For the unknown reason any of our 
observatories hasn't received socket alert on this burst (we have
received only auxiliary packages).

We have a number images with  60-s exposition.
We haven't found optical transient within Swift-XRT error-box.
The 3-sigma unfiltred upper limit has been about 17.0 mag on single and 
18.2 mag on 10 images coadd.

http://observ.pereplet.ru/images/GRB100526A/grb100526.jpeg


The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB100526B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10799
SUBJECT: GRB 100526B: Swift detection of a probable GRB
DATE:    10/05/26 19:13:54 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. H. Siegel (PSU), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC),
J. M. Gelbord (PSU), D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
D. M. Palmer (LANL), T. A. Pritchard (PSU), P. Romano (INAF-IASFPA),
T. Sakamoto (NASA/UMBC), M. A. Stark (PSU), E. Troja (NASA/GSFC/ORAU)
and L. Vetere (PSU) report on behalf of the Swift Team:

At 19:00:38 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100526B (trigger=423184).  The slew was delayed due to
an observing constraint.  The BAT on-board calculated location is 
RA, Dec 0.700, -37.902 which is 
   RA(J2000)  =  00h 02m 48s
   Dec(J2000) = -37d 54' 07"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a few weak peaks
with a duration of about ~30 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~3 sec after the trigger. 

Due to an observing constraint, Swift will not slew until 
T0+54 minutes. There will be no XRT or UVOT data until
this time. 

Burst Advocate for this burst is M. H. Siegel (siegel 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: GRB100526A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10800
SUBJECT: GRB 100526A: Enhanced Swift-XRT position
DATE:    10/05/26 19:50:41 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 1199 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 100526A, 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 = 230.76903, +25.63234 which is equivalent
to:

RA (J2000): 15h 23m 4.57s
Dec (J2000): +25d 37' 56.4"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100526A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10801
SUBJECT: GRB 100526A: Swift-BAT refined analysis
DATE:    10/05/26 20:11:43 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),
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), L. Vetere (PSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+303 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100526A (trigger #423181)
(Vetere, et al., GCN Circ. 10797).  The BAT ground-calculated position is
RA, Dec = 230.792, 25.623 deg which is 
   RA(J2000)  =  15h 23m 10.2s 
   Dec(J2000) = +25d 37' 24.4" 
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 26%.
 
The mask-weighted light curve shows a few overlapping peaks starting at
~T-70 sec, peaking around T-20 and at ~T+75 sec, and ending at ~T+115 sec.
T90 (15-350 keV) is 102 +- 8.5 sec (estimated error including systematics).
 
The time-averaged spectrum from T-33.2 to T+80.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.83 +- 0.17.  The fluence in the 15-150 keV band is 2.5 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+69.90 sec in the 15-150 keV band
is 0.7 +- 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/423181/BA/


GRB_name: GRB100526B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10802
SUBJECT: GRB 100526B: Swift XRT/UVOT observations
DATE:    10/05/26 20:30:55 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>

J. A. Kennea, L. Vetere and M. Siegel (PSU) report on behalf of the Swift 
team:

The XRT began observing the field of GRB 100526B at 19:55:21.1 UT, 3282.6 
seconds after the BAT trigger. Using promptly downlinked data we find an 
uncatalogued X-ray source located at RA, Dec 0.73552, -37.91195 which is 
equivalent to:
   RA(J2000)  = 00h 02m 56.52s
   Dec(J2000) = -37d 54' 43.0"
with an uncertainty of 5.6 arcseconds (radius, 90% containment). This 
location is 107 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.  We cannot 
determine whether the source is fading at the present time.

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.12e+20 cm^-2 (Kalberla et al. 2005).

UVOT took a finding chart exposure of 150 seconds with the White filter 
starting 3288 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 none of the XRT error circle. 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 0.01.


GRB_name: GRB100526B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10803
SUBJECT: GRB 100526B: Swift-BAT refined analysis
DATE:    10/05/26 21:58:32 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),
D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. H. Siegel (PSU),
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 the recent telemetry downlink,
we report further analysis of BAT GRB 100526B (trigger #423184)
(Siegel, et al., GCN Circ. 10799).  The BAT ground-calculated position is
RA, Dec = 0.777, -37.913 deg, which is 
   RA(J2000)  =  00h 03m 06.5s 
   Dec(J2000) = -37d 54' 48.4" 
with an uncertainty of 3.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 95%.
 
The mask-weighted light curve shows a broad weak peak starting at ~T-25 sec,
peaking around T+10 sec, and ending around t+50 sec.  The burst location
went out of the BAT FOV at T+240 sec when Swift was forced to slew due 
to an observing constraint.  T90 (15-350 keV) is 64.0 +- 22.6 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-28.4 to T+35.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.47 +- 0.28.  The fluence in the 15-150 keV band is 4.7 +- 0.9 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+11.15 sec in the 15-150 keV band
is 0.1 +- 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/423184/BA/


GRB_name: GRB100526A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10804
SUBJECT: GRB 100526A: Swift XRT refined analysis
DATE:    10/05/26 22:18:34 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

L. Vetere (PSU) reports on behalf of the Swift-XRT team:

We have analysed 1.6 ks of XRT data for GRB 100526A (Vetere et al. GCN  
Circ. 10797),
from 151 s to 5.0 ks after the BAT trigger. The data comprise 234 s in  
Windowed Timing
(WT) mode with the remainder in Photon Counting (PC) mode. The  
enhanced XRT
position for this burst was given by Beardmore et al. (GCN. Circ 10800).

The 0.3-10 keV light curve shows a multiple peak structure, with the  
main spike at about
T+200, followed by a fast decay with of alpha=3.24 (+/-0.08), followed  
by a break at
T+732 s to an alpha of 0.8 (+/-0.4).

A spectrum formed from the WT mode data can be fitted with an absorbed  
power-law
with a photon spectral index of 2.97 (+/-0.08). The best-fitting  
absorption column is 3.21
(+0.18, -0.17) x 10^21 cm^-2, in excess of the Galactic value of 3.8 x  
10^20 cm^-2
(Kalberla et al. 2005). The PC mode spectrum has a photon index of  
2.45 (+0.24, -0.22)
and a best-fitting absorption column of 1.8 (+0.6, -0.5) x 10^21  
cm^-2. The counts to
observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from  
this spectrum is
3.3 x 10^-11 (5.9 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of  
0.8, the count rate
at T+24 hours will be 0.011 count s^-1, corresponding to an observed  
(unabsorbed)
0.3-10 keV flux of 3.7 x 10^-13 (6.7 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/00423181.

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


GRB_name: GRB100526A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10805
SUBJECT: GRB 100526A: NOT optical upper limit
DATE:    10/05/27 02:36:52 GMT
FROM:    Dong Xu at DARK,NBI  <dong@astro.ku.dk>

D. Xu (Weizmann Inst.), D. Malesani (DARK/NBI), P. Jakobsson (Univ. 
Iceland), T. Augusteijn (NOT), A. Thygesen (NOT)
report on behalf of a larger collaboration:

We observed the field of GRB 100526A (Vetere et al., GCN 10797) with 
the NOT equipped with ALFOSC in the R and i filters. Observations 
started on May 26 at 22:43 and 23:10 UT in R and i, respectively (6.282 
and 6.742 hr after the GRB), and were affected by the closeby Moon (47 
deg away).

We do not detect any new object within the refined XRT error circle 
(Beardmore et al, GCN 10800) in both R and i bands. The limiting 
magnitude is R(Vega) ~ 23.8, calibrated against the SDSS catalog.

[GCN OPS NOTE(27may10): Per author's request, Augusteijn was added
to the author list.]


GRB_name: GRB100526A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10806
SUBJECT: GRB 100526A: Gemini/NIRI infrared afterglow candidate
DATE:    10/05/27 11:41:49 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley (UC Berkeley) reports on behalf of a larger collaboration:

We imaged the field of GRB 100526A (Vetere et al., GCN 10797) with the 
Near-InfraRed Imager (NIRI) on Gemini-North starting at 08:29 UT on 
2010-05-27.  We obtained 18 exposures of 60 seconds each in K-band and 
H-band.

At the edge of the XRT error circle (Beardmore et al., GCN 10800) we 
clearly detect a source with no SDSS counterpart in the K-band image. 
It is also present, but much fainter, in H-band.  The position (J2000) is:

RA  =  15:23:04.480
Dec = +25:37:55.23
(+/- 0.4")

Preliminary photometry relative to a single 2MASS star in the field 
(2MASS 1523017+2538260) gives:

K = 19.09 +/- 0.13  (t_mid = 16.21 hours)
H = 21.15 +/- 0.17  (t_mid = 16.75 hours)

This is an extremely red color, corresponding to a spectral slope of 
beta~5.5.  If this object is confirmed as the afterglow (rather than a 
host or background galaxy), its flux and color are reminiscent of GRB 
070306 (Jaunsen et al. 2008) at similar times.  That object had a visual 
extinction of A_V~5.5 mag and is among the most heavily extinguished 
afterglows known.  The large inferred XRT absorption column (Vetere et 
al., GCN 10804) of this event is also consistent with a highly 
dust-extinguished event at low to moderate redshift.

We thank Richard McDermid and the Gemini staff for acquiring these 
observations.


GRB_name: GRB100526A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10807
SUBJECT: GRB 100526A: Swift/UVOT Upper Limits
DATE:    10/05/27 18:23:49 GMT
FROM:    Tyler Pritchard at PSU  <tapritchard@astro.psu.edu>

T. A. Pritchard (PSU) and Vetere (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100526A
151 s after the BAT trigger (Vetere et al., GCN Circ. 10797).
No optical afterglow consistent with the enhanced XRT position
(A. P. Beardmore et al.,GCN Circ. 10800) is detected in the initial
UVOT exposures.

Preliminary 3-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC)
exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
--------------------------------------------------------------
white (FC)         151          301          147         >21.1
u (FC)             310          559          246         >20.1
white              151         7321          783         >22.4
v                  640         6296          313         >20.3
b                  565         7116          491         >21.5
u                  310         6911          717         >21.3
w1                 690         6706          471         >20.9
m2                4865         6501          393         >20.6
w2                 791         7374          263         >20.6

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.04 in the direction of the burst
(Schlegel et al. 1998)


GRB_name: GRB100526B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10808
SUBJECT: GRB 100526B: Swift/UVOT Upper Limits
DATE:    10/05/27 18:26:17 GMT
FROM:    Tyler Pritchard at PSU  <tapritchard@astro.psu.edu>

T. A. Pritchard (PSU) and Siegel (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100526B
3288 s after the BAT trigger (Siegel et al., GCN Circ. 10799).
No optical afterglow consistent with the XRT position
(Kennea et al., GCN Circ. 10802) is detected in the initial UVOT
exposures. Preliminary 3-sigma upper limits using the UVOT
photometric system (Poole et al. 2008, MNRAS, 383, 627) for the
first finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
--------------------------------------------------------------
white (FC)        3288         3438          147         >21.3
white             3288         4669          344         >21.7
v                 3445         5080          393         >20.2
b                 4265         5880          372         >20.7
u                 4060         5695          393         >20.5
w1                3855         5491          393         >20.7
m2                3650         3849          197         >19.9
w2                4675         4875          197         >20.3

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100526B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10809
SUBJECT: GRB 100526B: Swift-XRT confirmation of fading afterglow
DATE:    10/05/28 05:40:58 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

L. Vetere and M. H. Siegel (PSU) report on behalf of the Swift-XRT team:

We have now collected 5.7 ks of Swift-XRT Photon Counting mode data on  
the GRB 100526B (Siegel et al. GCN Circ. 10799), from 3289 s to 34.8 ks 
after the BAT trigger.

The source reported by Kennea et al. (GCN Circ. 10802) is now only
marginally detected, with a count rate of 1.5x10^-3 count s^-1
(corresponding to an observed flux of 7.1x10^-14 erg cm^-2 s^-1).

With this fading, we can confirm that this source is the X-ray
afterglow of GRB 100526B.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00423184.

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


GRB_name: GRB100528A
Detection_method: superAGILE
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10810
SUBJECT: GRB 100528A: SuperAGILE Localization of a Long GRB
DATE:    10/05/28 08:23:17 GMT
FROM:    Marco Feroci at IASF/INAF  <sa.grb@iasf-roma.inaf.it>

E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, F. Lazzarotto,
L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda
(INAF/IASF Rome), G. Barbiellini, F. Longo, E. Moretti (INFN Trieste),  
A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti,
F. Fuschino, M. Marisaldi, M. Galli (INAF/IASF Bologna),
A. Giuliani, A. Chen, S. Mereghetti, F. Perotti, P. Caraveo (INAF/IASF
Milan), M. Tavani, G. Pucella, V. Vittorini, A. Argan, A. Trois,
G. Piano, S. Sabatini (INAF/IASF Rome), A. Pellizzoni, M. Pilia
(INAF/OA Cagliari), S. Vercellone, F. D'Ammando (INAF/IASF Palermo),
P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Picozza, A. Morselli,
E. Striani, (INFN Roma-2), M. Prest, E. Vallazza (Universita'
dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1),
P. Giommi, C. Pittori, F. Lucarelli, P. Santolamazza, F. Verrecchia
(ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, report:

"SuperAGILE detected a gamma ray burst on 28 May 2010, at 01:48:05 UT.
The event had a duration of about 20 s in the 20-60 keV energy range,
with a single peak structure. Due to the AGILE spinning operative mode,   
the measured duration may be a lower limit.
The burst position was reconstructed as (RA, Dec)
(311.119, 27.810) deg, which is:

RA(J2000)  = 20h 44m 28.52s
Dec(J2000) = 27d 48' 35.80"

with an uncertainty of 5' radius. The given uncertainty accounts
for both the statistical and systematic errors.

AGILE MCAL reports significant detection above 1.4 MeV.
An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."

This message may be cited.


GRB_name: GRB100528A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10811
SUBJECT: GRB 100528A: Fermi GBM observation
DATE:    10/05/28 09:07:46 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

Arne Rau (MPE) and Alexander van der Horst (UAH)
report on behalf of the Fermi GBM Team:

"At 01:48:01.11 UT on 28 May 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100528A (trigger 296704083 / 100528075)
which was also detected by the SuperAGILE (Del Monte et al. 2010, GCN 10810).
The GBM on-ground location is consistent with the SuperAGILE position.
The angle from the Fermi LAT boresight is 53 degrees.

The GBM light curve shows a main peak followed by a fainter
second pulse with a duration (T90) of about 24.6 +/- 0.5s (50-300 keV).
The time-averaged spectrum from T0+0.003 s to T0+24.576 s is best fit
by a Band function with Epeak = 316.5 +/- 17.8 keV, alpha = -1.16 +/- 0.02,
and beta = -1.99 +/- 0.06 (CSTAT 1868.5 for 657 d.o.f.).

The event fluence (10-1000 keV) in this time interval is
(2.77 +/- 0.02) E-05 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0+8.576 s in the 10-1000 keV band
is 14.76 +/- 0.21 ph/s/cm^2.

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


GRB_name: GRB100526B
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10812
SUBJECT: GRB100526B: GROND Upper limits
DATE:    10/05/28 10:03:44 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 100526B: GROND Upper limits

P. Afonso (MPE), A. Nicuesa (Tautenburg Obs.), R. Filgas and J. Greiner
(all MPE Garching), report on behalf of the GROND team:

We observed the field of GRB 100526B (Swift trigger #423184 ; Siegel et
al., GCN #10799) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla
Observatory (Chile).

Observations started at 09:37 UT on March 27, 14.6 hours after the GRB
trigger, and were performed under strong wind.

We do not detect a source within the Swift-XRT error circle reported by
Kennea et al. (GCN #10802) in any of the GROND filters.
Stacked images with a total integration time of 28 minutes in JHK and 32
minutes in g'r'i'z' yield the following preliminary 3-sigma upper limits:


g' > 24.1
r' > 24.2
i' > 23.9
z' > 23.8
J  > 22.7
H  > 22.2
K  > 21.3


All magnitudes given above are in the AB system and are based on the GROND
zeropoints and 2MASS field stars. No correction has been applied for the
Galactic foreground extinction corresponding to a reddening of E_(B-V)=
0.012 in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB100528A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10813
SUBJECT: Swift UVOT and UVOT-enhanced XRT position for GRB 100528A 
DATE:    10/05/28 22:03:49 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

D. Grupe (PSU), M. Siegel (PSU), J. Gelbord (PSU),  P.A. Evans and
M.R. Goad (U. Leicester) report on behalf of the Swift team:

We report of the Swift UVOT and XRT detections of a bright source  
within the 5'
error radius of the SuperAGILE detected GRB 100528A (Del Monte et al.,
GCN Circ 10810) at a level of 2e-12 ergs/s/cm2 in the 0.3-10 keV band.
Swift started observing the field of GRB 100528A 42.5
ks after the AGILE detection and has observed it so far for 5 ks (two
orbits). At this point it is not obvious if the X-ray source is fading.
However, this X-ray source was not present during the ROSAT All-Sky
Survey. There is also an archival XMM data set that covers this
position (OBSID 0037990101, a 17ks exposure taken 2002-11-21).
There is no source detected at the position of the counter part.
Measuring the flux within a 30" radius of this position, the 4-sigma
upper limit of 5e-14 ergs/s/cm2 in the 0.2-12 keV band.  Most likely
the X-ray source found by the XRT is the X-ray afterglow of GRB 100528A.


Using 2497 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 =
311.14130, 27.80660 which is equivalent to:

RA (J2000):  20 44 33.92
Dec (J2000): +27 48 23.8

with an uncertainty of 2.1 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) and Evans
et al. (2009, MNRAS, 397, 1177).

Using 4985 s of UVOT data take in the u, v and White filters,
we identify a faint uncataloged source within the XRT error circle
at a position in the white images of RA,DEC=311.14130, 27.80660 which
is equivalent to:

RA (J2000): 20 44 33.92
Dec (J2000): +27 48 23.8

with a 90%-confidence interval of about 0.60 arc sec. Preliminary
magnitudes using the  UVOT photometric system (Poole et al. 2008,
MNRAS, 383, 627) are:

FILTER     T_start(s)  T_stop    Exposure        Mag
=========================================================
white      43296       49881      1632     20.96+-0.13
v          44124       50777      1721     20.01+-0.35
u          42469       49036      1632     20.63+-0.24
=========================================================

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.29 (Schlegel et al.,
1998, ApJS, 500, 525). The 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 team.


GRB_name: GRB100528A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10814
SUBJECT: GRB 100528A: NOT optical observation
DATE:    10/05/29 16:30:12 GMT
FROM:    Dong Xu at DARK,NBI  <dong@astro.ku.dk>

D. Xu (Weizmann Inst.), P. Jakobsson (Univ. Iceland), A. Irrgang (Karl 
Remeis Observatory & ECAP) report on behalf of a larger collaboration:

We observed the field of GRB 100528A (Del Monte et al., GCN 10810; Grupe 
et al., GCN 10813) with the NOT equipped with ALFOSC in the B, V, R, and 
i filters. Observations started on May 29 at 04:08 UT (26.34 hrs after 
the GRB). We obtained 3x180 s frames in each filter.

An optical source is found at the UVOT position (Grupe et al., GCN 
10813) and is clearly detected in the stacked frame in each filter. 
Preliminary analysis shows the following Vega magnitudes:

m(B)=21.71+/-0.06  (mid_time=26.4417 hr)
m(V)=20.95+/-0.03  (mid_time=26.6751 hr)
m(R)=20.48+/-0.02  (mid_time=26.9090 hr)
m(i)= 20.02+-0.02   (mid_time= 27.1415 hr),

which are mainly calibrated against the #1178-0655113 star in the USNO 
B1 catalog and the Galactic extinction is not taken into account.

The source is very likely the afterglow of GRB 100528A as there exists 
decay in the V filter compared with the measurement in Grupe et al. (GCN 
10813).


GRB_name: GRB100528A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10815
SUBJECT: GRB 100528A: GROND detection in all bands
DATE:    10/05/30 14:09:01 GMT
FROM:    Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>

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

We observed the field of GRB 100528A discovered by SuperAGILE (Del Monte et
al., GCN #10810) and observed also by Fermi/GBM (Rau & van der Horst, 
GCN #10811),
simultaneously in g'r'i'z'JHK with GROND (Greiner et al.2008, PASP 120, 
405)
mounted at the 2.2 m MPI/ESO telescope at La Silla Observatory (Chile).

Observations started at 07:49 UT on March 30, 54 hours after the GRB
trigger. At the position of the UVOT detection (Grupe et al., GCN #10813)
we detect and confirm the afterglow mentioned also by Xu et al. (GCN 
#10814).

Based on stacked images with a total integration time of 40 minutes in 
JHK and
50 minutes in g'r'i'z' we estimate the following preliminary magnitudes
(all in the AB system):

g' = 21.93+-0.08
r' = 21.56+-0.04
i' = 21.27+-0.05
z' = 21.36+-0.07
J  = 20.49+-0.10
H  = 20.25+-0.12
K  = 20.46+-0.21

All magnitudes given above are calibrated against SDSS and 2MASS field 
stars.
No correction has been applied for the large, uncertain Galactic foreground
extinction corresponding to a reddening of E(B-V)~ 0.22 in the direction
of the burst (Schlegel et al. 1998).


GRB_name: GRB100528A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10816
SUBJECT: GRB 100528A: Faulkes Telescope North Detection
DATE:    10/05/31 10:32:49 GMT
FROM:    Zach Cano at ARI/John Moores Liverpool  <zec@astro.livjm.ac.uk>

Z. Cano (Liverpool JMU) & D. Kopac (U. Ljubljana) report on behalf of a
larger collaboration:

On 2010 May 27 at 13:07:01 UT the 2-m Faulkes Telescope North (Hawaii)
began observing in the R and i' filters the SuperAGILE GRB 100528A (Del
Monte et al., GCN Circ. 10810), which was also detected by Fermi/GBM (Rau
& Van der Horst, GCN Circ. 10811).

We clearly detect the optical afterglow at the UVOT position (Grupe et
al., GCN Circ. 10813; Xu et al., GCN Circ. 10814; Afonso et al., GCN Circ.
10815) with the following magnitudes:

---------------------------------------------------------------------
  T-To (days)        Filter       magnitude        magnitude error
---------------------------------------------------------------------
     1.51              r'           20.98             0.06
     1.48              i'           20.88             0.08
---------------------------------------------------------------------

Photometry is calibrated and quoted with respect to SDSS stars in the field.


GRB_name: GRB100528A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10817
SUBJECT: Konus-Wind observation of GRB 100528A
DATE:    10/05/31 15:33:58 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 100528A localized by SuperAGILE (Del Monte et al., GCN 
10810) triggered Konus-Wind at T0=6483.610 s UT (01:48:03.610).

The burst light curve shows a main pulse with a duration of ~30 s 
followed by a much weaker and softer pulse at ~T0+44 s with a duration 
of ~15 s.

As observed by Konus-Wind the burst
had a fluence of 2.85(-0.19, +0.21)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+6.688 s
of 3.99(-0.58, +0.59)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+23.296 s) is well 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 = -1.28(-0.06, +0.07),  and
Ep = 382(-52, +69) keV (chi2 = 55.0/61 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy
photon index: beta < -2.28 (chi2 = 55.0/60 dof).

The spectrum accumulated over the burst maximum (from T0 to T0+6.912 s) 
is well fitted (in the 20 keV - 2 MeV range)
by a power law with exponential cutoff model with
alpha = -1.18 +/- 0.07,  and
Ep = 558(-85, +115) keV (chi2 = 71.4/61 dof).
Fitting by GRB (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy
photon index: beta < -2.43 (chi2 = 71.4/60 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/GRB100528_T06483/


GRB_name: GRB100526A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10818
SUBJECT: GRB 100526A: optical upper limit
DATE:    10/06/01 20:17:14 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of the Swift GRB 100526A (Vetere et al. GCN  10797)
with AZT-11 telescope of CrAO between (UT) May 26  21:34 -- 22:36 under
mean  seeing of about 3 arcsec. No objects is detected in enhanced XRT error
circle (Beardmore et al. GCN 10800).

The upper limit in a stacked image based on USNO-B1.0 star  1156-0223950 
(assuming R=18.44)  is following:

T0+      Filter,   Exposure, mag.
(mid, d)              (s)

0.2354   R       20x180    > 21.4


GRB_name: GRB100514A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10819
SUBJECT: GRB 100514A: CrAO optical observations
DATE:    10/06/01 20:19:58 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We re-observed the field of the Swift GRB 100514A (Markwardt  et al. GCN
10759) with Shajn telescope of CrAO in filter I between (UT) May, 16 23:21
and May, 17 00:54. We do not detect the afterglow  of GRB 100514A (Marshall
et al, GCN 10766; Rumyantsev et al, GCN 10767).

The upper limit based on USNO-B1.0 star 1191-0563318  (J2000) RA=
21:55:19.80 Dec= +29:10:10.0  (assuming  I=18.09)  is following:

T0+      Filter,   Exposure, mag.
(mid, d)              (s)

2.2182  I       64x60     >22.9

The combined images can be found  http://grb.rssi.ru/GRB100514A/ 


GRB_name: GRB100513A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10820
SUBJECT: GRB 100513A: CrAO optical observations
DATE:    10/06/01 20:26:58 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of the Swift GRB 100513A (Baumgartner  et al. GCN 
10746)
with Shajn telescope of  CrAO in R-filter between May, 13 (UT) 18:43 --  
20:38,  and in I-filter on May, 14 (UT)  19:47 -- 20:57 and  on May, 16 (UT) 
18:28 -- 20:20.
The afterglow (Morgan  et al. GCN  10747) is clearly detected on May, 13,14 
and not detected on May 16. The afterglow coordinates are (J2000) RA = 11 18 
26.85 Dec = +03 37 40.3 with uncertainty of 0.3 arcsec.

The photometry of  stacked images based on USNO-B1.0 star 0936-0206849 
(RA(J2000) = 11:18:37.91 Dec(J2000)=  +03:37:43.1)  assuming  R=18.59 
I=17.88 is following:

T0+      Filter,   Exposure,  mag.                Upper Limit
(mid, d)              (s)



0.7313   R       104x60        23.03 +/- 0.12  24.3
1.7573   I          64x60        21.59 +/- 0.07  23.6

3.7202   I          91x60        >23.5                23.5



The combined images can be found at http://grb.rssi.ru/GRB100513A/



Using above photometry combined with reported earlier (R = 21.39 at 2.46 
hours, GCN 10750; J-filter photometry in GCNs 10747, 10749; i'=21.3 at 9.89 
hours, GCN 10757) one can suggest taht power law index of decay light curve 
in J, R and I- bandpass is compatible and equal to ~0.7 in the first day. 
The break of power law can be assumed in I-band between first and third days 
with power law decay index > 2.


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10821
SUBJECT: GRB 100418A: Maidanak optical observations
DATE:    10/06/01 20:31:58 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of the Swift GRB 100418A (Marshall  et al. GCN 10612) 
with AZT-22 telescope of Maidanak observatory on  (UT) Apr. 22 (22:34 --  
23:35) and May 7 (22:49 -- 23:27). The optical afterglow (Marshall  et al. 
GCN 10612, Filgas et al. GCN 10617) is detected in single images on  Apr. 22 
and in a stacked image on May 7. The photometry of the afterglow based on 
USNO-B1.0 star 1014-0271368  (RA(J2000) = 17:05:26.42 Dec(J2000)= 
+11:27:32.9)  assuming R=17.32  is following:

T0+      Filter,   Exposure, seeing, mag.
(mid, d)              (s)

 4.0793     R       11x300    0.7 20.56 +/- 0.02

19.0821    R         6x300    1.3 22.05 +/- 0.25


GRB_name: GRB100111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10822
SUBJECT: GRB 100111A: Maidanak optical observations
DATE:    10/06/01 20:34:43 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the afterglow of the Swift GRB 100111A (Vetere et al. GCN 10317) 
with AZT-22 (1.5 m) telescope of Maidanak observatory (MAO) in R band on 
Jan. 12 (UT) (00:44 - 01:32) under good weather conditions with mean seeing 
of about 0.8 arcsec. The optical afterglow (Vetere et al. GCN 10317) is 
clearly detected in enhanced XRT error
circle (Beardmore et al. GCN 10321). A photometry of combined image is based 
on several SDSS DR7 field stars:

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


0.8687         R       8*300   22.92 +/- 0.18  23.56

Comparing with R-magnitude reported by Xu et al. (GCN 10318) (R=19.46+/-0.05 
in 0.05 days) one can obtain power-law decay index of about 1.12.


GRB_name: GRB100606A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10824
SUBJECT: GRB 100606A: Swift detection of a burst
DATE:    10/06/06 19:23:43 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), S. Campana (INAF-OAB),
P. A. Curran (UCL-MSSL), P. A. Evans (U Leicester),
N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), O. M. Littlejohns (U Leicester),
C. B. Markwardt (CRESST/GSFC/UMD), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL),
P. Romano (INAF-IASFPA), A. Rowlinson (U Leicester),
T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), R. L. C. Starling (U Leicester),
E. Troja (NASA/GSFC/ORAU), T. N. Ukwatta (GSFC/GWU) and
L. Vetere (PSU) report on behalf of the Swift Team:

At 19:12:41 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100606A (trigger=424031).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is RA, Dec 350.603, -66.236 which is 
   RA(J2000) = 23h 22m 25s
   Dec(J2000) = -66d 14' 07"
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 at least 30 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 19:14:18.2 UT, 96.4 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 350.6246, -66.2434 which is equivalent to:
   RA(J2000)  = 23h 22m 29.90s
   Dec(J2000) = -66d 14' 36.2"
with an uncertainty of 5.2 arcseconds (radius, 90% containment). This
location is 41 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 2.5 s image was 1.70e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 106 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 19.6 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
0.03. 

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: GRB100606A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10825
SUBJECT: GRB 100606A: Prompt enhanced Swift-XRT position
DATE:    10/06/06 20:01:25 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:

Using 1374.0 ks of promptly downlinked XRT event data for GRB 100606A,
we find an enhanced XRT position of the afterglow: RA, Dec: 350.6265,
-66.2411 which is equivalent to:
   RA (J2000)  = 23 22 30.37
   Dec (J2000) = -66 14 28.1
with an uncertainty of 2.0 arc sec (radius, 90% confidence). Analysis
of the promptly available data is online at
http://www.swift.ac.uk/sper/424031.

Position enhancement is is described by Goad et al. (2007, A&A, 476,
1401) and Evans et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100606A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10827
SUBJECT: GRB 100606A: Enhanced Swift-XRT position
DATE:    10/06/06 22:40:37 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 1354 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 100606A, 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 = 350.62704, -66.24127 which is equivalent
to:

RA (J2000): 23h 22m 30.49s
Dec (J2000): -66d 14' 28.6"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100606A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10828
SUBJECT: GRB 100606A: Swift-BAT refined analysis
DATE:    10/06/07 04:23:39 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), N. Gehrels (GSFC), C. B. Markwardt (GSFC/UMD),
S. R. Oates (UCL-MSSL), 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 100606A (trigger #424031)
(Oates, et al., GCN Circ. 10824).  The BAT ground-calculated position is
RA, Dec = 350.617, -66.234 deg, which is 
   RA(J2000)  =  23h 22m 28.1s 
   Dec(J2000) = -66d 14' 03.3" 
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 25%.
 
The mask-weighted light curve shows an initial FRED peak starting at ~T-0.2 sec,
peaking at ~T+0.5 sec.  Then there are two peaks at ~T+12 and ~T+20 sec
followed by a roughly exponential decay out to ~T+180 sec.  Another, weak peak
occurs at ~T+200 followed by some very weak emission out to ~T+370 sec,
and possibly out to ~T+500 sec.  T90 (15-350 keV) is 480 +- 150 sec
(estimated error including systematics).
 
The time-averaged spectrum from T+0.3 to T+672.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.35 +- 0.10.  The fluence in the 15-150 keV band is 6.4 +- 0.4 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+7.82 sec in the 15-150 keV band
is 1.6 +- 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/424031/BA/


GRB_name: GRB100606A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10829
SUBJECT: GRB 100606A Swift-XRT refined analysis
DATE:    10/06/07 09:09:46 GMT
FROM:    Owen Littlejohns at U of Leicester  <oml2@star.le.ac.uk>

O. Littlejohns, P. A. Evans, J. P. Osborne (U. Leicester) and S. R.
Oates (UCL-MSSL) report on behalf of the Swift-XRT team:

We have analysed 4.9 ks of XRT data for GRB 100606A (Oates et al. GCN
Circ. 10824), from 86 s to 19.1 ks after the BAT trigger. The data
comprise 313 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Evans et al.
(GCN. Circ 10825).

The light curve can be modelled with a series of power-law decays. The
light curve initially shows some flaring with an underlying decay index
of 1.69 (+0.14, -0.10) from T+138 s to T+455 s. The light curve then
breaks at T+455 s to a decay with alpha=0.88 (+0.15, -0.26), flares may
also be present in this interval, before a final break at T+1641 s after
which the decay index is 2.09 (+1.28, -0.16).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.61 (+/-0.08). The
best-fitting absorption column is 2.06 (+0.29, -0.28) x 10^21 cm^-2, in
excess of the Galactic value of 2.4 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 1.91 (+0.15, -0.14)
and a best-fitting absorption column of 2.2 (+0.5, -0.4) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.4 x 10^-11 (6.2 x 10^-11) erg cm^-2
count^-1.

If the light curve continues to decay with a power-law decay index of
2.09, the count rate at T+24 hours will be 2.9 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x
10^-14 (1.8 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/00424031.

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


GRB_name: GRB100606A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10830
SUBJECT: GRB 100606A: Swift/UVOT Upper Limits
DATE:    10/06/07 11:09:41 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (MSSL-UCL) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 100606A 107s after the BAT trigger (Oates et al., GCN Circ. 10824).
We do not detect any source at the enhanced Swift XRT position
(Evans et al. GCN Circ. 10827).

The 3-sigma upper limits for the finding chart exposures (FC)
and summed images are:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white (FC) 107      256      147        > 21.08
u     (FC) 319      568      246        > 20.35
white      598      6542     461        > 21.70
v          648      6952     333        > 19.86
b          574      6337     312        > 20.76
u         722      7567     487        > 20.47
uvw1       698      7362     490        > 20.54
uvm2      673      7157     274        > 19.93
uvw2       1030     6748     255        > 20.27
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction due to the reddening of E_(B-V) = 0.03 mag
along the line of sight. All photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB100606A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10831
SUBJECT: GRB 100606A: Gemini-South imaging
DATE:    10/06/07 13:21:32 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

A.J. Levan (U. Warwick) and N.R. Tanvir (U. Leicester) report for
a larger collaboration:

We imaged the location of GRB 100606A (Oates et al. GCN 10824)
using GMOS-S on Gemini South. Observations began at 06:02 UT on June 7th,
approximately 11 hours after the burst, and were obtained in the r, i and 
z-bands, with a total of 900s exposure in each band. Within the refined 
XRT error circle (Evans et al. GCN 10827) we find a faint, and apparently
extended source, with r~25 (using archival zero point), which is barely 
visible in our i and z-band observations, suggesting a relatively blue 
colour. Although it is plausible that this object contains some 
contribution from a faint afterglow, the extended source is apparently 
dominating, and we suggest that this is the host of GRB 100606A.

The faint afterglow (r>25), combined with the apparently high X-ray
column density (Littlejohns et al. GCN 10829) is consistent with
GRB 100606A as a highly extinguished burst.

We thank the staff of Gemini South, especially Peter Pessev, for
the help in acquiring these data.


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10832
SUBJECT: Radio detection of GRB100418a with ATCA
DATE:    10/06/07 14:41:27 GMT
FROM:    Aquib Moin at CIRA/ATNF  <aquib.moin@postgrad.curtin.edu.au>

Aquib Moin (Curtin Institute of Radio Astronomy / International Centre for Radio Astronomy Research / CSIRO Astronomy and Space Science) 

Steven Tingay (Curtin Institute of Radio Astronomy / International Centre for Radio Astronomy Research) 

Chris Phillips (CSIRO Astronomy and Space Science) 

Gregory Taylor (University of New Mexico) 

Mark Wieringa (CSIRO Astronomy and Space Science)

Ralph Martin (Perth Observatory) report:

We observed the field of Swift GRB100418a (GCN 10612, GCN 10614, GCN 10616) at 5.5 GHz and 9.0 GHz with the Australia Telescope Compact Array (ATCA) between 12:30:00 UT and 19:30:00 UT on May 26, 2010.

We clearly detected the radio afterglow at the optical afterglow position of the GRB 100418a (GCN 10616) at both frequencies with flux densities 0.91 +/- 0.04 mJy and 1.46 +/- 0.07 mJy respectively. 

Further observations are planned.

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 GRB 100418a field images:

http://cira.ivec.org/dokuwiki/doku.php/grb/grb100418a


GRB_name: GRB100606A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10833
SUBJECT: Konus-Wind observation of GRB 100606A
DATE:    10/06/08 10:17:03 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100606A (Swift-BAT trigger=424031;
Oates et al., GCN 10824; Krimm et al., GCN 10828)
triggered Konus-Wind at T0=69163.712s UT (19:12:43.712)

The total duration of the burst is ~100 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100606_T69163/

As observed by Konus-Wind the burst
had a fluence of 3.9(+/-0.5)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+0.256s
of 2.5(+/-0.25)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+82.176 s) is best fit
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -1.05(+/-0.14),
and Ep = 945(-266, +551) keV;
chi2 = 49/58 dof.

The spectrum at the maximum count rate
(measured from T0 to T0+8.448 s) is best fit
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.68(+/-0.15),
and Ep = 767(-126, +175) keV;
chi2 = 72/58 dof.

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


GRB_name: GRB100606A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10835
SUBJECT: GRB 100606A: GROND observations
DATE:    10/06/09 12:15:27 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

A. Nicuesa (TLS Tautenburg), T. Kruehler and J. Greiner (MPE
Garching) report on behalf of the GROND team:

We observed the field of GRB 100606A (Oates et al., GCN 10824)
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP
120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla
Observatory (Chile).

Observations started at 04:27 UT on June 07, 9.2 hours after the
GRB trigger.

Within the enhanced XRT error circle (Evans et al. GCN 10827)
we confirm the presence of the blue and extended source reported by
Levan et al. (GCN 10831) in g' and r' at

RA (J2000) = 23:22:30.27
Dec (J2000) = -66:14:27.1

with typical uncertainties of 0.5" in each coordinate.

Similar to Levan et al. (GCN 10831) we also do not find evidence of an 
optical/NIR afterglow.

Stacked images of 270 min total integration time in g'r'i'z' and
80 min in JHK yield the following preliminary upper limits
in the AB system, which have been obtained using the GROND zeropoints
and 2MASS field stars as reference:

g' > 25.7 (24.7 +- 0.2)
r' > 25.5 (25.0 +- 0.3)
i' > 24.6
z' > 24.1
J  > 22.2
H  > 21.5
K  > 21.0

Magnitudes in brackets denote the brightness of the putative host galaxy.

Using the r'-band upper limit and the X-ray brightness at a similar 
time, beta_oX is constrained to be smaller than 0.6, implying that the 
burst would not be necessarily 'dark' according to the Jakobsson et al. 
(2004, ApJ, 617, 21) classification. Thus, our limit neither implies 
large redshift nor large extinction.


GRB_name: GRB100606A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10836
SUBJECT: GRB 100606A: Suzaku WAM observation of the prompt emission
DATE:    10/06/12 16:46:30 GMT
FROM:    Satoshi Sugita at Aoyama Gakuin U.  <sugita@phys.aoyama.ac.jp>

S. Sugita (Nagoya U.), K. Yamaoka (Aoyama Gakuin U.),
A. Daikyuji, N. Ohmori, Y. Nishioka, M. Yamauchi (Univ. of Miyazaki),
Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.),
Y. Terada, M. Tashiro, S. Hong, W. Iwakiri, K. Takahara, T. Yasuda (Saitama
U.),
M. Ohno, M. Kokubun, T. Takahashi (ISAS/JAXA), Y. E. Nakagawa,
M. Suzuki, T. Tamagawa (RIKEN), N. Vasquez (Tokyo Tech.),  Y. Urata,
H. M. Lin, P. P. Tsai (NCU), T. Enoto, K. Nakazawa, K. Makishima
(Univ. of Tokyo) on behalf of the Suzaku WAM team, report:

The long GRB 100606A (Swift/BAT trigger #10824; Oates et al.,)
triggered the Suzaku Wide-band  All-sky Monitor (WAM)
which covers an energy range of 50 keV - 5 MeV at 19:12:41.766 UT (=T0).

The observed light curve shows a multi-peaked structure
lasting from T0-2s to T0+100s with a duration  (T90) of about 65 seconds.
The fluence in 100 - 1000 keV was 2.21 (-0.28, +0.17) x10^-5 erg/cm^2.
The 1-s peak flux measured from T0+1s was 3.40 (-0.41 +0.28)  photons/cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0 to T0+65s is well fitted by a power-law with exponential cutoff model:
dN/dE =  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha       0.63 (-0.30 +0.25), and
Epeak      767 (-121 +172)  keV (chi^2/d.o.f. = 45.2/52).

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: GRB100614A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10837
SUBJECT: GRB 100614A: Swift detection of a burst
DATE:    10/06/14 22:09:01 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

G. Stratta (ASDC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), V. D'Elia (ASDC),
J. M. Gelbord (PSU), C. Gronwall (PSU),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (UCL-MSSL),
W.B Landsman (GSFC), J. Mao (INAF-OAB), F. E. Marshall (NASA/GSFC),
J. P. Osborne (U Leicester), T. Sakamoto (NASA/UMBC),
C. J. Saxton (UCL-MSSL), B. Sbarufatti (INAF-OAB/IASFPA),
M. Stamatikos (OSU/NASA/GSFC), T. N. Ukwatta (GSFC/GWU) and
L. Vetere (PSU) report on behalf of the Swift Team:

At 21:38:26 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100614A (trigger=424716).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 263.519, +49.227, which is 
   RA(J2000)  =  17h 34m 05s
   Dec(J2000) = +49d 13' 36"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is typical for image triggers, the TDRSS
lightcurve does not show anything significant. 

The XRT began observing the field at 21:40:39.1 UT, 133.0 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
263.4992, 49.2347 which is equivalent to:
   RA(J2000)  = 17h 33m 59.81s
   Dec(J2000) = +49d 14' 05.1"
with an uncertainty of 2.1 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 in excess of the Galactic value (2.2e+20
cm^-2, Kalberla et al. 2005), with an excess column of 1.3
(+1.11/-1.03) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 0.1 s image was 4.41e-08 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of nominal 250 seconds with the U filter
starting 873 seconds after the BAT trigger.  No white observations were taken
because there is a V = 7.4 star in the UVOT field of view.  The UVOT image covers
100% of the XRT error circle.  No credible afterglow candidate has been found in 
the initial data products to an estimated magnitude limit of u > 19.2.  No 
correction has been made for the expected extinction  corresponding to E(B-V) of 
0.03 mag. 

Burst Advocate for this burst is G. Stratta (giulia.stratta 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: GRB100614A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10838
SUBJECT: GRB 100614A: Liverpool Telescope Observations
DATE:    10/06/14 23:07:02 GMT
FROM:    Carole Mundell at ARI, JMU,Liverpool  <cgm@astro.livjm.ac.uk>

C.G. Mundell and I.A. Steele (Liverpool JMU) report on behalf of a larger 
collaboration:

"The 2-m Liverpool Telescope robotically followed up GRB100614A
(SWIFT trigger 424716; Stratta et al. GCN10837) 17.07 min after the GRB 
trigger time. Initial analysis shows no optical counterpart is detected in 
the XRT error circle to the following limiting magnitudes (wrt USNOB1):

Time from trigger      Filter  Limiting Mag
-----------------     -------  ------------
29 mins           R      > 21 mag
31 mins    i' > 21 mag

We note also that no counterpart is detected in z'-band images.

Observations and analysis are ongoing.

This message may be cited"


GRB_name: GRB100614A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10839
SUBJECT: GRB 100614A: BOOTES-2/TELMA optical observations
DATE:    10/06/14 23:16:03 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

M. Jelinek, A. J. Castro-Tirado (IAA-CSIC Granada), P. Kubanek (IAA-CSIC 
and IPL-UV) and A. de Ugarte Postigo (OAB), on behalf of a larger 
collaboration, report:

"The TELMA 0.6m robotic telescope at the BOOTES-2 astronomical station 
in South Spain has responded to GRB 100614A 18s after the GCN notice 
(and about 6.9 min after the onset of the GRB).  The co-add of 36 images 
(3-s each, unfiltered) obtained through cirrusses provides a R = 18 
limiting magnitude at the position of the X-ray atterglow (Stratta et 
al. GCNC 10837)."

This message can be quoted.


GRB_name: GRB100614A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10840
SUBJECT: GRB 100614A: WHT I-band observations
DATE:    10/06/15 01:32:15 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick), N.R. Tanvir (U. Leicester) and P. Groot
(Nijmegen) report for a larger collaboration:

"We obtained imaging of GRB 100614A (Stratta et al. GCN 10837) with 
the 4.2m William Herschel Telescope (WHT). Observations began at 
22:38 UT, approximately 1.0 hours after the burst. A total of 1200s 
integration was obtained in the I-band. Within the refined XRT 
position we do not locate any obvious sources to a preliminary 
limiting magnitude of I>24."


GRB_name: GRB100615A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10841
SUBJECT: GRB 100615A: Swift detection of a burst
DATE:    10/06/15 02:13:23 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

V. D'Elia (ASDC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC),
J. M. Gelbord (PSU), S. T. Holland (CRESST/USRA/GSFC),
C. B. Markwardt (CRESST/GSFC/UMD), T. Sakamoto (NASA/UMBC),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC), G. Stratta (ASDC),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 01:59:03 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100615A (trigger=424733).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 177.207, -19.496 which is 
   RA(J2000)  =  11h 48m 50s
   Dec(J2000) = -19d 29' 45"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows 3 strong peaks
with a duration of about 60 sec.  The peak count rate
was ~7000 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The XRT began observing the field at 02:00:06.4 UT, 62.4 seconds after
the BAT trigger. Using promptly downlinked data we find a bright, fading,
uncatalogued X-ray source located at RA, Dec 177.20376, -19.48169 which
is equivalent to:
   RA(J2000)  = 11h 48m 48.90s
   Dec(J2000) = -19d 28' 54.1"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 52 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 (3.28e+20
cm^-2, Kalberla et al. 2005), with an excess column of 1.3
(+0.47/-0.39) x 10^22 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 6.15e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 71 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 19.6 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
0.05. 

Burst Advocate for this burst is V. D'Elia (delia 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: GRB100615A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10842
SUBJECT: GRB 100615A: NTT/Ultracam imaging
DATE:    10/06/15 04:14:30 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

V. Dhillon (U. Sheffield), R. Mignani (MSSL), S. Schulze (U. Iceland),
A. J. Levan (U. Warwick), N. R. Tanvir (U. Leicester), A. de Cia (U. 
Iceland) report on behalf of the ULTRACAM collaboration:

We observed the field of GRB 100615A (D'Elia et al., GCN 10841) with 
ULTRACAM (Dhillon et al., MNRAS, 2007, 378, 825) mounted on the 3.5-m NTT 
telescope on La Silla, beginning approximately 17 mins post-burst.

Stacking the images from 02:16:27 to 02:39:29 UT did not reveal any new
source down to 24 mag (3 sigma) in the i' band.

The deep limiting magnitude at early times, coupled with bright X-ray
afterglow with moderate hydrogen column density (D'Elia et al. GCN 10841)
is suggestive of a highly extinguished burst.


GRB_name: GRB100615A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10843
SUBJECT: GRB 100615A: PAIRITEL NIR Upper Limits
DATE:    10/06/15 05:41:52 GMT
FROM:    Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>

A. N. Morgan C. R. Klein, and J. S. Bloom (UC Berkeley) report:

We observed the field of GRB 100615A (D'Elia et al., GCN 10841) with
the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began
at 2010-06-15 03h21m51 UT, ~1.4 hours after the Swift Trigger, under
high airmass (~2), and continued until the source set beyond telescope
limits.  In  mosaics (effective exposure time of 0.56 hours) taken
simultaneously in the J, H, and Ks filters, we do not detect any
source within the XRT error circle.

The preliminary photometry yields:

post burst
t_mid (hr) exp.(hr) filt  U. Limit (3 sig)
1.94      0.56     J     > 18.8
1.94      0.56     H     > 17.9
1.94      0.56     Ks    > 16.6

All magnitudes are given in the Vega system, calibrated to 2MASS. No
correction for Galactic extinction has been made to the above reported
values.


GRB_name: GRB100615A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10844
SUBJECT: GRB 100615A: GROND observations, upper limits
DATE:    10/06/15 05:47:41 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

A. Nicuesa, S. Klose (both TLS Tautenburg), and J. Greiner (MPE Garching), 
report on behalf of the GROND team:

GROND (Greiner et al. 2008, PASP 120, 405), the 7-channel imager mounted 
at the 2.2m ESO/MPI telescope on La Silla, started follow-up observations 
of GRB 100615A (D'Elia et al. 2010, GCN 10841) on June 15 at 2:05 UT 
(about 6 min after the trigger).

Within the 3.7 arcsec XRT error circle we do not find any afterglow 
candidate. Preliminary measured upper limits based on an 8 min observing 
block starting at 2:20 UT are (in the AB system, 3 sigma):

g' > 24.2,
r' > 23.9,
i' > 22.9,
z' > 22.5,
J  > 21.4,
H  > 20.7,
K  > 20.3,

using GROND zeropoints and the 2MASS catalog. This is in agreement with 
the report by Dhillon et al. about the non-detection in the i' band (GCN 
10842).


GRB_name: GRB100614A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10845
SUBJECT: GRB 100614 :  XMM-Newton observation
DATE:    10/06/15 07:16:47 GMT
FROM:    Norbert Schartel at XMM-Newton/ESA  <too@xmm.esac.esa.int>

XMM-Newton is observing GRB 100614 (RA=17h 34m 05s, DEC=+49d 13' 16", J2000),
starting at 04:12 UT, on June 15, 2010, for an exposure of 42 ksec.


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GRB_name: GRB100614A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10846
SUBJECT: GRB 100614A: Swift-XRT refined analysis
DATE:    10/06/15 10:01:56 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti, B. Sbarufatti (INAF-OAB) and G. Stratta (ASDC) report on
behalf of the Swift-XRT team:

We have analysed 1.4 ks of XRT data for GRB 100614A (Stratta et al. GCN
Circ. 10837), from 136 s to 1.6 ks after the BAT trigger. The data
comprise 319 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. The light curve can be modelled with an initial
power-law decay with an index of alpha=1.79 (+/-0.11) followed by a break
around T+300 s to an alpha of 2.51 (+0.12, -0.10). X-ray flaring activity
is detected in the first 300 s of observation.

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.84 (+/-0.05). The best-fitting
absorption column is 1.80 (+/-0.15) x 10^21 cm^-2, in excess of the
Galactic value of 2.2 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode
spectrum has a photon index of 1.92 (+0.21, -0.20) and a best-fitting
absorption column of 1.0 (+/-0.5) x 10^21 cm^-2. The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum
is 4.1 x 10^-11 (5.1 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of
2.51, the count rate at T+24 hours will be 1.3 x 10^-5 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.2 x 10^-16
(6.5 x 10^-16) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00424716.

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


GRB_name: GRB100615A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10847
SUBJECT: GRB 100615A: Swift-XRT refined analysis
DATE:    10/06/15 10:02:44 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti, B. Sbarufatti (INAF-OAB) and V. D'Elia (ASDC) report on
behalf of the Swift-XRT team:

We have analysed 1.1 ks of XRT data for GRB 100615A (D'Elia et al. GCN
Circ. 10841), from 68 s to 1.2 ks after the BAT trigger. The data comprise
73 s in Windowed Timing (WT) mode with the remainder in Photon Counting
(PC) mode. The light curve can be modelled with an initial power-law decay
with an index of alpha=4.17 (+0.23, -0.22), followed by a break at T+191 s
to an alpha of -0.03 (+0.23, -0.25).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.21 (+0.16, -0.15). The
best-fitting absorption column is 8.8 (+1.1, -1.0) x 10^21 cm^-2, in
excess of the Galactic value of 3.3 x 10^20 cm^-2 (Kalberla et al. 2005).
The PC mode spectrum has a photon index of 2.6 (+0.4, -0.3) and a
best-fitting absorption column of 1.18 (+0.29, -0.25) x 10^22 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced
from this spectrum is 4.9 x 10^-11 (1.9 x 10^-10) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of
-0.03, the count rate at T+24 hours will be 1.4 count s^-1, corresponding
to an observed (unabsorbed) 0.3-10 keV flux of 6.8 x 10^-11 (2.6 x 10^-10)
erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00424733.

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


GRB_name: GRB100615A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10848
SUBJECT: GRB 100615A: Enhanced Swift-XRT position
DATE:    10/06/15 10:21:14 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 1489 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 100615A, 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 = 177.20522, -19.48118 which is equivalent
to:

RA (J2000): 11h 48m 49.25s
Dec (J2000): -19d 28' 52.2"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100614A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10849
SUBJECT: GRB 100614A: Enhanced Swift-XRT position
DATE:    10/06/15 11:50:36 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 3444 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 100614A, 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 = 263.49923, +49.23434 which is equivalent
to:

RA (J2000): 17h 33m 59.82s
Dec (J2000): +49d 14' 03.6"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100615A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10850
SUBJECT: GRB 100615A: Swift-BAT refined analysis
DATE:    10/06/15 11:59:42 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), V. D'Elia (ASDC), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), A. M. Parsons (GSFC),
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-61 to T+242 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 100615A (trigger #424733)
(D'Elia, et al., GCN Circ. 10841).  The BAT ground-calculated position is
RA, Dec = 177.208, -19.483 deg, which is 
   RA(J2000)  =  11h 48m 49.9s 
   Dec(J2000) = -19d 29' 00.0" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 99%.
 
The mask-weighted light curve shows 3 slightly overlapping FRED peaks
with the first starting at ~T-0.2 sec and peaking at ~T+2 sec.  The second
peaks at ~T+10 sec.  The third peaks at ~T+30 sec and ends at ~T+~120 sec.
T90 (15-350 keV) is 39 +- 2 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.0 to T+47.4 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.87 +- 0.04.  The fluence in the 15-150 keV band is 5.0 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+10.26 sec in the 15-150 keV band
is 5.4 +- 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/424733/BA/


GRB_name: GRB100615A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10851
SUBJECT: GRB 100615A: Fermi GBM detection
DATE:    10/06/15 13:47:12 GMT
FROM:    Suzanne Foley at MPE  <sfoley@mpe.mpg.de>

S. Foley (MPE) and M. Briggs (UAH)
report on behalf of the Fermi GBM Team:

"At 01:59:04.37 UT on 15 June 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100615A (trigger 298259946 / 100615083)
which was also detected by the SWIFT-BAT
(D'Elia et al. 2010, GCN 10841).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 64 degrees.

The GBM light curve consists of 3 main pulses
with a duration (T90) of about 37.7 +/- 0.8 s (10-1000 keV).
The time-averaged spectrum from T0+0.003 s to T0+39.553 s is
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.34 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 106.20 (+7.53/-6.07) keV
(CSTAT 989.31 for 606 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(8.64 +/- 0.17)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+9.7 s in the 8-1000 keV band
is 8.3 +/- 0.2 ph/s/cm^2.

A Band function fits the spectrum equally well (CSTAT 976.41 for 605 d.o.f.)
with Epeak = 85.73 (+7.82/-9.33) keV, alpha = -1.24 (+0.08/-0.06) and
beta = -2.27 (+0.11/-0.12).


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


GRB_name: GRB100614A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10852
SUBJECT: GRB 100614A: Swift-BAT refined analysis
DATE:    10/06/15 13:59:10 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), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), M. Stamatikos (GSFC/ORAU),
G. Stratta (ASDC), 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 100614A (trigger #424716)
(Stratta, et al., GCN Circ. 10837).  The BAT ground-calculated position is
RA, Dec = 263.534, 49.232 deg which is 
   RA(J2000)  =  17h 34m 08.2s 
   Dec(J2000) = +49d 13' 56.4" 
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 56%.
 
The mask-weighted light curve shows a relatively smooth peak starting
at ~T-10 sec, peaking around T+50 sec, and ending at ~T+275 sec.
T90 (15-350 keV) is 225 +- 55 sec (estimated error including systematics).
 
The time-averaged spectrum from T-9.0 to T+282.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.88 +- 0.15.  The fluence in the 15-150 keV band is 2.7 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+31.00 sec in the 15-150 keV band
is 0.7 +- 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/424716/BA/


GRB_name: GRB100614A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10853
SUBJECT: GRB 100614A: MASTER-Net  optical alert observations 
DATE:    10/06/15 14:22:59 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, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov,
M. Kornilov
Sternberg Astronomical Institute, Moscow State University

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


V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk


V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka

K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, 
O.Chuvalaev
Irkutsk State University

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located near Kislovodsk   was pointed to the  GRB 100614A (Stratta et al., 
GCN 10837) 26 s after notice time and 7 min 59 s after GRB time in two
polarizations at 2010-06-14 21:46:25 UT.

We have a number images with  180-s exposition.
We haven't found optical transient within Swift-XRT error-box.
The 3-sigma unfiltred upper limit has been about 20.9 mag on  34 
coadded images (21:46:25  -  22:42:05 UT).

The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB100614A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10854
SUBJECT: GRB 100614A: NOT optical upper limits
DATE:    10/06/15 16:34:46 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

D. Malesani (DARK/NBI), D. Xu (Weizmann Inst.), T. Pursimo (NOT), P. 
Jakobsson (Univ. Iceland), report on behalf of a larger collaboration:

We observed the field of GRB 100614A (Stratta et al., GCN 10837) with 
the NOT equipped with ALFOSC. Observations were carried out in the R, I, 
and z filters, with mean times 54, 79, and 107 minutes after the GRB 
trigger, respectively.

We do not detect any source within the refined XRT error circle (Osborne 
et al., GCN 10849) in any of our images. The limiting magnitudes are R > 
24.0, I > 22.8 calibrated against the USNO-B1 catalog (calibration of 
the z-band data is not presently feasible). Our findings are in 
agreement with non-detections reported by other groups (Mundell & 
Steele, GCN 10838; Jelinek et al., GCN 10839; Levan et al., GCN 10840; 
Gorbovskoy et al., GCN 10853).

We acknowledge prompt reaction and careful assistence of the NOT staff.


GRB_name: GRB100614A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10855
SUBJECT: GRB 100614A: Swift/UVOT Upper Limits
DATE:    10/06/15 19:20:53 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <Stephen.T.Holland@nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) and
G. Stratta (ASDC)
report on the behalf of the Swift UVOT team:

      The Swift/UVOT observed the field of GRB 100614A starting 123 s
after the BAT trigger (Stratta, et al., 2010, GCN Circ. 10837).
Settled observations started at 139 s.  No white observations were
taken due to the presence of the bright A0 star HD 159607 (V = 7.4)
located 11.5 arcmin from the XRT source.  We do not find any new
source, relative to the DSS, USNO-B1.0, or 2MASS at the position of
the XRT afterglow (Osborne, et al. 2010, GCN Circ. 10849).
Preliminary 3-sigma upper limits for detecting a source in the u-band
finding chart, and in the co-added images, using a 2.5 arcsecond
radius circular aperture, are

Filter    T_start   T_stop   Exp(s)      Mag
--------------------------------------------
 u (fc)       139      339      246    >21.0

 v            445   12,065     1218    >21.4
 b            395     7165      549    >21.8
 u            139     6960      897    >21.7
 uvw1         494   13,145      675    >21.2
 uvm2         770   12,970     1102    >21.4
 uvw2         421     7365      484    >21.1
--------------------------------------------

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} = 0.03 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: GRB100615A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10856
SUBJECT: GRB 100615A: Swift/UVOT Upper Limits
DATE:    10/06/15 19:21:44 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <Stephen.T.Holland@nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) and
V. D'Elia (ASDC)
report on the behalf of the Swift UVOT team:

      The Swift/UVOT observed the field of GRB 100615A starting 53 s
after the BAT trigger (D'Elia, et al., 2010, GCN Circ. 10841).
Settled observations started at 72 s.  We do not find any new source,
relative to the DSS, USNO-B1.0, or 2MASS at the position of the XRT
afterglow (Goad, et al. 2010, GCN Circ. 10848).  Preliminary 3-sigma
upper limits for detecting a source in the finding charts, and in the
co-added images, using a 2.5 arcsecond radius circular aperture, are

Filter    T_start   T_stop   Exp(s)      Mag
--------------------------------------------
white (fc)     72      222      147    >21.5
              864     1014      147    >21.5
u (fc)        284      534      246    >20.7

v             613     7037      510    >20.6
b             539     6422      490    >21.1
u             284     6216      539    >21.1
uvw1          663     7436      499    >21.1
uvm2          813     7242      413    >20.7
uvw2          589     6832      471    >21.1
white          72     6627      785    >22.2
--------------------------------------------

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} = 0.05 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: GRB100614A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10857
SUBJECT: GRB 100614A: Swift/UVOT Upper Limits
DATE:    10/06/15 19:32:34 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) and
G. Stratta (ASDC)
report on the behalf of the Swift UVOT team:

     The Swift/UVOT observed the field of GRB 100614A starting 123 s
after the BAT trigger (Stratta, et al., 2010, GCN Circ. 10837).
Settled observations started at 139 s.  No white observations were
taken due to the presence of the bright A0 star HD 159607 (V = 7.4)
located 11.5 arcmin from the XRT source.  We do not find any new
source, relative to the DSS, USNO-B1.0, or 2MASS at the position of
the XRT afterglow (Osborne, et al. 2010, GCN Circ. 10849).
Preliminary 3-sigma upper limits for detecting a source in the u-band
finding chart, and in the co-added images, using a 2.5 arcsecond
radius circular aperture, are

Filter    T_start   T_stop   Exp(s)      Mag
--------------------------------------------
u (fc)       139      339      246    >21.0

v            445   12,065     1218    >21.4
b            395     7165      549    >21.8
u            139     6960      897    >21.7
uvw1         494   13,145      675    >21.2
uvm2         770   12,970     1102    >21.4
uvw2         421     7365      484    >21.1
--------------------------------------------

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} = 0.03 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).

[GCN OPS NOTE(08mar13):  This is a duplicate submission of 10855.
Acknowledgement to F.Marshall for pointing this out.]


GRB_name: GRB100615A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10858
SUBJECT: GRB 100615A: Swift/UVOT Upper Limits
DATE:    10/06/15 19:32:42 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) and
V. D'Elia (ASDC)
report on the behalf of the Swift UVOT team:

     The Swift/UVOT observed the field of GRB 100615A starting 53 s
after the BAT trigger (D'Elia, et al., 2010, GCN Circ. 10841).
Settled observations started at 72 s.  We do not find any new source,
relative to the DSS, USNO-B1.0, or 2MASS at the position of the XRT
afterglow (Goad, et al. 2010, GCN Circ. 10848).  Preliminary 3-sigma
upper limits for detecting a source in the finding charts, and in the
co-added images, using a 2.5 arcsecond radius circular aperture, are

Filter    T_start   T_stop   Exp(s)      Mag
--------------------------------------------
white (fc)     72      222      147    >21.5
              864     1014      147    >21.5
u (fc)        284      534      246    >20.7

v             613     7037      510    >20.6
b             539     6422      490    >21.1
u             284     6216      539    >21.1
uvw1          663     7436      499    >21.1
uvm2          813     7242      413    >20.7
uvw2          589     6832      471    >21.1
white          72     6627      785    >22.2
--------------------------------------------

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} = 0.05 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).

[GCN OPS NOTE(08mar13):  This is a duplicate submission of 10856.
Acknowledgement to F.Marshall for pointing this out.]


GRB_name: GRB100615A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10861
SUBJECT: GRB 100615A: Gemini/NIRI Observations
DATE:    10/06/16 17:04:00 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, D. A. Perley (UC Berkeley), N. R. Tanvir (U. Leicester), A.
J. Levan (U. Warwick), J. S. Bloom, B. E. Cobb (UC Berkeley), K. Wiersema
(U. Leicester) report on behalf of a larger collaboration:

We have imaged the field of GRB100615A (D'Elia et al., GCN 10841) with the
Near InfraRed Imager on the 8-m Gemini North telescope.  Observations were
obtained in the J and K filters beginning at 7:36 UT on 15 June 2010 (~
5.5 hours after the trigger).

We find no sources inside the revised XRT error circle (Goad et al., GCN
10848) to limiting magnitudes of J > 22.1, K > 20.9 (Vega, calibrated with
respect to 2MASS).  Combined with additional limits from other facilities
(Dhillon et al., GCN 10842; Morgan et al., GCN 10843; Nicuesa et al., GCN
10844; Holland and D'Elia, GCN 10856), and the large excess X-ray column
derived from XRT observations (Margutti et al., GCN 10847), we conclude
that GRB100615A is likely a highly extinguished event.


GRB_name: GRB100614A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10862
SUBJECT: GRB 100614A: Gemini/NIRI Observations
DATE:    10/06/16 17:22:59 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, D. A. Perley (UC Berkeley), N. R. Tanvir (U. Leicester), A.
J. Levan (U. Warwick), J. S. Bloom, B. E. Cobb (UC Berkeley), K. Wiersema
(U. Leicester) report on behalf of a larger collaboration:

We have imaged the field of GRB100614A (Stratta et al., GCN 10837) with
the Gemini Near InfraRed Imager on the 8-m Gemini North telescope.
Observations were obtained in the Y, J, and K filters beginning at 7:05 UT
on 15 June 2010 (~ 9.5 hours after the burst).

We find no sources inside the revised XRT error circle (Osborne et al.,
GCN 10849) to limiting magnitudes of J > 22.7, K > 21.6 (Vega mags,
calibrated with respect to 2MASS).  The lack of optical/NIR detections at
other facilities (Mundell and Steele, GCN 10838; Jelinek et al., GCN
10839; Levan et al., GCN 10840; Gorbovskoy et al., GCN 10853, Malesani et
al., GCN 10854, Holland and Stratta, GCN 10857), coupled with the moderate
excess column inferred from the XRT spectrum (Margutti et al., GCN 10846),
suggest a highly extinguished optical/NIR afterglow.


GRB_name: GRB100619A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10863
SUBJECT: GRB 100619A: Swift detection of a burst
DATE:    10/06/19 00:37:25 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

J. K. Cannizzo (NASA/UMBC), N. Gehrels (NASA/GSFC),
J. M. Gelbord (PSU), S. T. Holland (CRESST/USRA/GSFC),
J. Mao (INAF-OAB), R. Margutti (INAF-OAB), F. E. Marshall (NASA/GSFC),
D. M. Palmer (LANL), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), M. A. Stark (PSU) and T. N. Ukwatta (GSFC/GWU)
report on behalf of the Swift Team:

At 00:21:07 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100619A (trigger=424998).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 84.615, -27.001 which is 
   RA(J2000) = 05h 38m 28s
   Dec(J2000) = -27d 00' 02"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed two well-separated
peaks about 90 seconds apart with an overall duration of about 120 sec. 
The peak count rate was ~4000 counts/sec (15-350 keV), at ~0 sec after
the trigger for the first peak, and 5000 counts/sec (15-350 keV) at
~95 sec after the trigger for the second peak. 

The XRT began observing the field at 00:22:23.7 UT, 76.4 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
84.6227, -27.0049 which is equivalent to:
   RA(J2000)  = 05h 38m 29.46s
   Dec(J2000) = -27d 00' 17.8"
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This
location is 27 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 (2e+20
cm^-2, Kalberla et al. 2005), with an excess column of 3.8
(+1.95/-1.69) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 0.1 s image was 5.61e-08 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White
filter starting 87 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 19.6 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 0.03. 

Burst Advocate for this burst is J. K. Cannizzo (cannizzo 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: GRB100619A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10864
SUBJECT: GRB 100619A: Swift-BAT refined analysis
DATE:    10/06/19 10:12:10 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. K. Cannizzo (NASA/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), 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 100619A (trigger #424998)
(Cannizzo, et al., GCN Circ. 10863).  The BAT ground-calculated position is
RA, Dec = 84.618, -27.012 deg which is 
   RA(J2000)  =  05h 38m 28.3s 
   Dec(J2000) = -27d 00' 42.2" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
 
The mask-weighted light curve shows two well separated peaks.  The first
s compsed of several overlapping pulses which starts at ~T-3 sec, peaks at
~T_10 sec, and returns to background at ~T+20 sec.  The second peak starts
~T+55 sec, peaks at ~T=85 sec, and ends at ~T+120 sec.  T90 (15-350 keV)
is 97.5 +- 3 sec (estimated error including systematics).
 
The time-averaged spectrum from T-2.9 to T+105.7 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.83 +- 0.06.  The fluence in the 15-150 keV band is 4.5 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+87.22 sec in the 15-150 keV band
is 4.8 +- 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/424998/BA/


GRB_name: GRB100619A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10865
SUBJECT: GRB 100619A: Enhanced Swift-XRT position
DATE:    10/06/19 10:14:39 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 4927 s of XRT Photon Counting mode data and 8 UVOT
images for GRB 100619A, 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 = 84.62214, -27.00534 which is equivalent
to:

RA (J2000): 05h 38m 29.31s
Dec (J2000): -27d 00' 19.2"

with an uncertainty of 1.5 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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100619A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10866
SUBJECT: GRB 100619A: Swift-XRT refind analysis
DATE:    10/06/19 12:07:18 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao (INAF-OAB) and J. K. Cannizzo (NASA/UMBC) report on behalf of the
Swift-XRT team:

We have analysed 6.6 ks of XRT data for GRB 100619A (Cannizzo  et al.
GCN Circ. 10863), from 80 s to 13.2 ks after the  BAT trigger. The data
comprise 492 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The light curve initially shows a flare feature
at the time 90s, then it has a power-law decay with an index 0.88, after 
that,
the light curve shows a clear flare feature with the peak at 1000s. 
Then, the
light cure has a power-law decay with an index of alpha=0.85 (+/-0.02).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.41 (+/-0.03). The
best-fitting absorption column is  3.4 (+/-0.1) x 1021 cm^-2, in
excess of the Galactic value of 2.0 x 1020 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 2.16 (+0.20, -0.19)
and a best-fitting absorption column of 3.7 (+/-0.6) x 1021 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 6.7 x 10^-11 (9.6 x 10^-11) erg cm^-2
count^-1. If the light curve continues to decay with a power-law decay 
index
of 0.85, the count rate at T+24 hours will be 0.015 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.0 x
10^-12 (1.4 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00424998.

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


GRB_name: GRB100619A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10867
SUBJECT: GRB 100619A: Swift/UVOT Upper Limits
DATE:    10/06/19 13:15:56 GMT
FROM:    Peter Curran at MSSL  <pac@mssl.ucl.ac.uk>

P.A. Curran (MSSL-UCL) and J. K. Cannizzo (NASA/UMBC) report on behalf
of the Swift/UVOT team:


The Swift/UVOT began settled observations of the field of GRB 100619A 87 
s after the BAT trigger (Cannizzo et al., GCN Circ. 10863). No optical 
afterglow consistent with the enhanced  XRT position (Beardmore et al., 
GCN Circ. 10865) is detected in the initial UVOT exposures. Preliminary 
3-sigma upper limits using the UVOT photometric system (Poole et al. 
2008, MNRAS, 383, 627) for the first finding chart (FC) and subsequent 
exposures are:


Filter   T_start(s)  T_stop(s)  Exp(s)   Mag
-----------------------------------------------
white    87          237        147      >21.2 (FC)
u        300         549        246      >20.5 (FC)

white    87          6773       785      >22.0
v        630         7184       510      >20.2
b        556         13220      1161     >21.5
u        300         19002      2089     >21.6
w1       679         18300      2128     >21.7
m2       654         17394      1396     >21.4
w2       606         6978       510      >20.9


The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100619A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10868
SUBJECT: GRB 100619A: Fermi GBM detection
DATE:    10/06/20 14:52:19 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 03:55:23.71 UT on 19 June 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100619A (trigger 298612525 / 100619015).
which was also detected by the SWIFT-BAT (Cannizzo et al. 2008, GCN 10863)
The GBM on-ground location is consistent with the Swift position.
 
The angle from the Fermi LAT boresight is 117 degrees.

The GBM light curve shows 2 well separated pulses
with a duration (T90) of about 96.8 s (50-300 keV).
The time-averaged spectrum from T0-9.216 s to T0+101.378 s is
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.61 +/- 0.05 and
the cutoff energy, parameterized as Epeak, is 143.2 +/- 24.8 keV

(C-stat 419 for 241 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.71 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+83 s in the 10-1000 keV band is 1.88 +/- 0.04 ph/s/cm^2.

A Band function fits the spectrum equally well (C-stat 419 for 240 d.o.f.)
with Epeak= 135.3 +/- 37.1 keV, alpha = -1.60 +/- 0.07 and beta = -2.36 +/-
0.69. 


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


GRB_name: GRB100606A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10869
SUBJECT: GRB 100606A: Optical Limits
DATE:    10/06/21 00:33:42 GMT
FROM:    Brian Schmidt at RSAA, ANU (MSSSO)  <brian@mso.anu.edu.au>

S.Rapoport, J. Scharwaechter, B.P. Schmidt, M.Dopita, M. Bessell
RSAA, The Australian National University report

We observed the afterglow of the Swift GRB 100606A (S.R. Oates
et al. GCN 10824) with the Australian National University's 
Wide-Field-Spectrograph
(WiFeS)+2.3m telescope located at Siding Spring
Observatory. WiFeS is a high throughput integral field spectrograph 
which covers a FoV of 25"x38"
(Dopita, M., et al, , Ap&SS,310,255).
The spectra  were taken in poor conditions (FWHM 3 arcsec ) at the onset of
twilight, and cover the wavelength region 3200A-9300A
at a resolution of 3000. Data were obtained  in two 900 second exposures
commencing at UT 19:49:20 Jun 6 (35 minutes after GRB trigger).
To maximize image depth, we stacked and remove spectra regions containing
skylines to form g,r,i,z images. We did not detect any source within the XRT
error circle to limiting magnitudes (5-sigma) of

Filter       Mag
       (AB)
===       ===
g          >18.1
r          >19.5
i           >19.1
z          >18.9

calibrated by comparison to a nearby spectrophometric standard star.
The values are not corrected for galactic extinction.


GRB_name: GRB100621A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10870
SUBJECT: GRB 100621A: Swift detection of a burst
DATE:    10/06/21 03:16:45 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. N. Ukwatta (GSFC/GWU), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), V. D'Elia (ASDC),
N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU),
S. T. Holland (CRESST/USRA/GSFC), C. B. Markwardt (CRESST/GSFC/UMD),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC), M. A. Stark (PSU)
and G. Stratta (ASDC) report on behalf of the Swift Team:

At 03:03:32 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100621A (trigger=425151).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 315.308, -51.086 which is 
   RA(J2000) = 21h 01m 14s
   Dec(J2000) = -51d 05' 10"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a triple-peaked
structure with a duration of about 100 sec.  The peak count rate
was ~25,000 counts/sec (15-350 keV), at ~25 sec after the trigger. 

The XRT began observing the field at 03:04:48.8 UT, 76.0 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 315.3004, -51.1063 which is equivalent to:
   RA(J2000)  = 21h 01m 12.09s
   Dec(J2000) = -51d 06' 22.6"
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This
location is 73 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 7.49e-08 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 84 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 19.6 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
0.03. 

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: GRB100621A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10871
SUBJECT: GRB 100621A: ROTSE-III Optical Limits
DATE:    10/06/21 03:40:05 GMT
FROM:    Shashi Bhushan Pandey at ROTSE  <shaship@umich.edu>

S. B. Pandey (U Mich), W. Rujopakarn (Steward), T. Guver (U Arizona), W.
Zheng (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 100621A (Swift trigger 425151; Ukwatta T. N., GCN 10870),
producing images beginning 5.0 s after the GCN notice time. An automated
response took the first image at 03:04:05.0 UT, 32.2 s after the burst, and
during the gamma-ray emission, under fair conditions. We took 10 5-sec, 10
20-sec and 10 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 or the XRT error circle; the field is not
crowded. Individual images have limiting magnitudes ranging from 16.1-17.3;
we set the following specific limits.

start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
03:04:05.0 03:04:10.0 5 16.1 32.2 N
03:05:30.0 03:09:13.0 200 18.4 232.2 Y


GRB_name: GRB100621A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10872
SUBJECT: GRB 100621A: Prompt enhanced Swift-XRT position
DATE:    10/06/21 03:56:48 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:

Using 0 s of promptly downlinked XRT event data for GRB 100621A, we
find an enhanced XRT position of the afterglow: RA, Dec: 315.3052,
-51.1060 which is equivalent to:
   RA (J2000)  = 21 01 13.24
   Dec (J2000) = -51 06 21.7
with an uncertainty of 2.0 arc sec (radius, 90% confidence). Analysis
of the promptly available data is online at
http://www.swift.ac.uk/sper/425151.

Position enhancement is is described by Goad et al. (2007, A&A, 476,
1401) and Evans et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100621A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10873
SUBJECT: GRB 100621A: Enhanced Swift-XRT position
DATE:    10/06/21 09:33:26 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 3262 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 100621A, 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 = 315.30466, -51.10624 which is equivalent
to:

RA (J2000): 21h 01m 13.12s
Dec (J2000): -51d 06' 22.5"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100621A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10874
SUBJECT: GRB 100621A: GROND observation of bright NIR afterglow
DATE:    10/06/21 09:56:56 GMT
FROM:    Jochen Greiner at MPI  <jcg@mpe.mpg.de>

Adria Updike (Clemson Univ.), Ana Nicuesa (Tautenburg Obs.), Marco Nardini, 
Thomas Kruehler and Jochen Greiner (all MPE Garching) report on behalf of 
the GROND team:

We observed the field of GRB 100621A (Swift trigger 425151; Ukwatta et  
al., GCN #10870) simultaneously in g'r'i'z'JHK with GROND (Greiner et  
al. 2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La  
Silla Observatory (Chile). Observations started at 03:07 UT on June 21st, 
4 minutes after the GRB trigger, and continued for 3 hours. They were 
performed at an average seeing of 1.5" under clear sky conditions.

In stacked images of 6 min total integration time in g'r'i'z' and 8 min in JHK,
centered at 03:20 UT, we detect a bright, uncatalogued NIR source within the 
Swift/XRT error circle (Evans et al. GCN #10872) at the following coordinates:
RA (2000.0)  =  21h 01m 13.08s
DEC (2000.0) = -51d 06' 22.5"
with an error of +-0.3". This coincides with the enhanced XRT position
(Evans et al. 2010, GCN #10873).

In the first hour the source faded by about 1 mag in the JHK bands, 
thus we identify this object as the GRB afterglow of GRB 100621A.

Our preliminary photometry centered at 03:45 UT is (in AB  
magnitudes):

g' = 22.7+-0.4  
r' = 21.6+-0.1
i' = 20.5+-0.1  
z' = 19.7+-0.1
J  = 17.3+-0.1
H  = 16.3+-0.1, and
K  = 15.8+-0.1

These magnitudes were derived by calibrating the images against the GROND 
zeropoints and 2MASS field stars and are not corrected for the Galactic 
foreground extinction corresponding to a reddening of E_(B-V)= 0.03 in the 
direction of the burst (Schlegel et al. 1998).

We note that there are indications of this source in the DSS2 images.
Also, there is no fading in the g' band, suggesting that this is the
underlying host galaxy at a redshift smaller than about 3. The extremely 
red colour then is likely due to severe intrinsic dust extinction. 

We encourage spectroscopic observations.


GRB_name: GRB100621A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10875
SUBJECT: GRB 100621A: Swift-BAT refined analysis
DATE:    10/06/21 13:10:27 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), 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),
(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 100621A (trigger #425151)
(Ukwatta, et al., GCN Circ. 10870).  The BAT ground-calculated position is
RA, Dec = 315.309, -51.102 deg, which is 
   RA(J2000)  =  21h 01m 14.1s 
   Dec(J2000) = -51d 06' 08.8" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 97%.
 
The mask-weighted light curve shows three main overlapping peaks starting
at ~T-8 sec, with the main peak at ~T+25 sec, and ending at ~T+220 sec.
T90 (15-350 keV) is 63.6 +- 1.7 sec (estimated error including systematics).
 
The time-averaged spectrum from T-6 to T+204 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.90 +- 0.03.  The fluence in the 15-150 keV band is 2.1 +- 0.0 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+24.46 sec in the 15-150 keV band
is 12.8 +- 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/425151/BA/


GRB_name: GRB100621A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10876
SUBJECT: GRB 100621A: VLT/X-shooter redshift
DATE:    10/06/21 14:00:38 GMT
FROM:    Bo Milvang-Jensen at Dark Cosmology Centre,NBI,U. Copenhagen  <milvang@astro.ku.dk>

B. Milvang-Jensen (DARK/NBI), P. Goldoni (APC/Univ. Paris 7 and SAp/CEA),
N. R. Tanvir, K. Wiersema (Univ. Leicester), D. Malesani (DARK/NBI),
A. de Ugarte Postigo (INAF-OAB), V. D'Elia (INAF-OAR and ASDC),
S. D. Vergani (GEPI/Obs. Paris and APC/Univ. Paris 7),
J. P. U. Fynbo (DARK/NBI), L. Kaper (Univ. Amsterdam),
J. Sollerman (Univ. Stockholm), on behalf of the X-shooter GRB
collaboration, and 
A. Updike (Clemson Univ.), J. Greiner, T. Kruehler (MPE Garching),
on behalf of the GROND team, report:

We observed the optical afterglow of GRB 100621A (Ukwatta et al., GCN
10870; Updike et al., GCN 10874) with the ESO VLT equipped with the
X-shooter spectrograph. The afterglow was detected in the I-band
acquisition image. Four spectra lasting 10 minutes each were obtained,
covering the spectral range 3000-25000 AA, starting on 2010 June 21,
at 10:09 UT (7.1 hr after the GRB); the observations were done during
twilight. Preliminary inspection of the spectrum reveals emission
features which we interpret as due to [O II] 3727, Hbeta and the
[O III] doublet from the underlying host galaxy, at a common redshift
z = 0.542. The [O II] line is very weak. This, together with the low
redshift and the optically faint and red afterglow supports high
extinction internal to the host (Updike et al., GCN 10874).

We caution that the data reduction was carried out using archival
calibration files. We acknowledge a particularly helpful and attentive
support from the ESO staff in Paranal: M. Olivares, T. Rivinius,
C. Ledoux, C. Martayan, and the visiting astronomers: F. Ferraro,
B. Lanzoni.


GRB_name: GRB100621A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10877
SUBJECT: GRB 100621A: Swift XRT refined analysis
DATE:    10/06/21 14:10:13 GMT
FROM:    Giulia Stratta at ASDC  <giulia.stratta@gmail.com>

G. Stratta (ASDC), V. D'Elia (ASDC) and T. N. Ukwatta (GSFC/GWU) report on
behalf of the Swift-XRT team:

We have analysed 3.6 ks of XRT data for GRB 100621A (Ukwatta et al. GCN
Circ. 10870), from 79 s to 7.0 ks after the BAT trigger. The data comprise
322 s in Windowed Timing (WT) mode with the remainder in Photon Counting
(PC) mode. The enhanced XRT position for this burst was given by Evans et
al. (GCN. Circ 10872).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=3.41 (+0.11, -0.18). At T+153 s the decay
steepens to an alpha of 4.34 (+0.20, -0.12) before breaking again at T+389 s
to a final decay with index alpha=0.55 (+0.13, -0.07).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.73 (+0.07, -0.06). The
best-fitting absorption column is 6.11 (+0.27, -0.26) x 10^21 cm^-2, in
excess of the Galactic value of 2.9 x 10^20 cm^-2 (Kalberla et al. 2005).
The PC mode spectrum has a photon index of 2.15 (+0.17, -0.16) and a
best-fitting absorption column of 6.6 (+1.0, -0.9) x 10^21 cm^-2. The counts
to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum is 5.0 x 10^-11 (1.0 x 10^-10) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 0.55,
the count rate at T+24 hours will be 0.23 count s^-1, corresponding to an
observed (unabsorbed) 0.3-10 keV flux of 1.1 x 10^-11 (2.4 x 10^-11) erg
cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00425151.

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


GRB_name: GRB100621A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10878
SUBJECT: GRB 100621A: Swift/UVOT observations
DATE:    10/06/21 14:30:51 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (MSSL-UCL) and T. N. Ukwatta (GSFC/GWU) report on behalf  
of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 100621A 85s after the BAT trigger (Ukwatta et al., GCN 10870).
We detect a source at the enhanced Swift XRT position
(Evans et al. GCN 10873) and at the location of the GROND source
(Updike et al. GCN 10874). This source is also observed in the
DSS and observed to be constant during the first 7000s and is
thus likely to be the host galaxy, which is also suggested by Updike
et al. (GCN 10874).

The magnitudes and 3-sigma upper limits for the finding chart  
exposures (FC)
and summed images for this possible host galaxy are:

Filter     T_start   T_stop   Exp(s)  Magnitude/3-sigma upper limit
-------------------------------------------------------------
white (FC)    85     234        147     20.87 +/- 0.35
white         576    7093       519     20.46 +/- 0.15
u     (FC)    297    546        246         > 20.18
u             700    6683       360         > 20.14
v             626    6067       391     19.49 +/- 0.31
b             552    6888       372     20.27 +/- 0.28
uvw1          1107   6478       352     19.64 +/- 0.25
uvm2          6073   6273       197         > 19.66
uvw2          5663   5863       197     19.60 +/- 0.28
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.03 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).


GRB_name: GRB100619A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10879
SUBJECT: GRB 100619A: Correction to the Fermi GBM trigger time
DATE:    10/06/21 18:37:43 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:

"The trigger time of GRB 100619A reported in GCN 10868 as 03:55:23.71 UT is
in error. The actual trigger time is 00:21:07.03 UT."


GRB_name: GRB100621A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10880
SUBJECT: GRB 100621A MOA-II optical limit
DATE:    10/06/22 01:04:15 GMT
FROM:    Takashi Sako at Nagoya U./MOA  <sako@stelab.nagoya-u.ac.jp>

D. Suzuki, F. Hayashi, S.Kobara, T. Sako, H. Naito, K. Omori  (STE Lab, Nagoya Univ.)
on behalf of the MOA Collaboration report:

We searched for an optical afterglow of GRB 100621A (GCN 10870, T. N. Ukwatta et al.)
starting from 09:02 UT on 2010 June 21st (6 hours after the burst) with the
MOA-II 1.8m telescope at Mt.John observatory in New Zealand.
In a single image of a 300sec exposure with a wide-band Red filter (center
wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object
within the error circle of the Swift XRT source position (GCN 10873).
A 3 sigma upper limit is set in the I magnitude at 22.23 mag.

This photometry was done by using the DoPhot and calibrated against the
USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.


GRB_name: GRB100621A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10881
SUBJECT: GRB 100621A: IRSF/SIRIUS NIR Observation
DATE:    10/06/22 15:37:21 GMT
FROM:    Hiroyuki Naito at Nagoya U  <naito@stelab.nagoya-u.ac.jp>

H. Naito, T. Sako, D. Suzuki, S. Kobara and K. Omori (Nagoya Univ.) on  
behalf of the MOA Collaboration,
T. Nagayama, M. Kurita (Nagoya Univ.) and N. Oi (The Graduate  
University for Advanced Studies/NAOJ)
on behalf of the IRSF Collabration report:

We searched for a NIR afterglow of GRB 100621A (Ukwatta et al., GCN  
10870) starting from
04:02 to 04:51 UT on 2010 June 21 with the SIRIUS on the IRSF 1.4m  
telescope at SAAO in
South Africa. In images of a 300 sec exposure with J, H and Ks filter,  
we detected an new source
within the error circle of the enhanced Swift XRT position (Evans et  
al., GCN 10873) and at the
location of the GROND source (Updike et al., GCN 10874) . The  
estimated magnitudes are the
followings.

---------------------------------------------------------------
Mid time from   Total Exp.   J-mag*   H-mag*   K-mag*
trigger (min)     (s)
---------------------------------------------------------------
61.41                 300              16.56      15.22      14.18
67.61                 300              16.24      14.63      13.84
73.84                 300              15.27      13.78      12.63
80.14                 300              15.07      13.57      12.40
86.36                 300              14.93      13.45      12.23
92.56                 300              14.90      13.45      12.32
98.81                 300              14.93      13.47      12.34
105.0                 300              15.04      13.55      12.36
---------------------------------------------------------------
*Typical error is ~ 0.1 mag

This photometry was done by using the DoPhot and calibrated against  
the 2MASS catalog stars,
and not corrected for the Galactic extinction. The source was  
brightened up by >1mag during our
observation period while the other field stars were reasonably stable.


GRB_name: GRB100621A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10882
SUBJECT: Konus-Wind observation of GRB 100621A
DATE:    10/06/23 10:22:55 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100621A (Swift-BAT trigger=425151;
Ukwatta et al., GCN 10870; Ukwatta et al., GCN 10875)
triggered Konus-Wind at T0=11013.352s UT (03:03:33.352)

The burst light curve shows multiple overlapping peaks
with a total duration of ~80 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100621_T11013/

As observed by Konus-Wind the burst
had a fluence of 3.6(+/-0.4)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+26.880s
of 1.70(+/-0.13)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+73.984 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -1.70 (+/-0.13),
the high energy photon index beta = -2.45 ( <-2.3 ),
the peak energy Ep = 95(-13, +18)keV (chi2 = 65/57 dof).

The spectrum at the maximum count rate
(measured from T0+24.832 to T0+33.024 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -1.15 (-0.2/+0.3),
the high energy photon index beta = -2.8 (-0.7/+0.3),
the peak energy Ep = 83(+/-9)keV (chi2 = 64/57 dof).

Assuming z=0.542 (Milvang-Jensen et al., GCN 10876) 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 = 2.8(+/-0.3)x10^52 erg,
the peak luminosity (L_iso)_max = (2.04+/-0.16)x10^51 erg/s.

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


GRB_name: GRB100418A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10883
SUBJECT: GRB 100418A: late time optical observations
DATE:    10/06/25 16:45:00 GMT
FROM:    Vasilij Rumjantsev at CrAO  <rum@crao.crimea.ua>

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

We observed the field of the Swift GRB 100418A (Marshall et al. GCN
10612) with Shajn telescope of CrAO between (UT) June, 11 20:07 --
21:50 under photometric weather conditions and mean seeing of about 2
arcsec. The preliminary photometry of the afterglow+host in a stacked
image based on USNO-B1.0 star 1014-0271368 (RA(J2000) = 17:05:26.42
Dec(J2000)= +11:27:32.9) assuming R=17.32 is following:

T0+      Filter,   Exposure,  mag.
(mid, d)              (s)

53.9919     R       88x60    22.05 +/-0.07

The brightness of the host is less but compatible with early reported
magnitudes on May 14 (R = 21.86 +/-0.06; GCN 10783) and (Rc = 21.90
+/-0.03; GCN 10794)


GRB_name: GRB100625A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10884
SUBJECT: GRB 100625A: Swift detection of a short hard burst
DATE:    10/06/25 18:42:40 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. T. Holland (CRESST/USRA/GSFC), D. N. Burrows (PSU),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
W.B Landsman (GSFC), O. M. Littlejohns (U Leicester),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
D. M. Palmer (LANL), A. Rowlinson (U Leicester),
T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC) and
R. L. C. Starling (U Leicester) report on behalf of the Swift Team:

At 18:32:28 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100625A (trigger=425647).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 15.771, -39.083 which is 
   RA(J2000) = 01h 03m 05s
   Dec(J2000) = -39d 04' 57"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single
peak with substructure with a duration of about 0.4 sec.  The peak
count rate was ~19,000 counts/sec (15-350 keV), at ~0.3 sec after the trigger. 

The XRT began observing the field at 18:33:16.7 UT, 48.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 15.79489, -39.08833 which
is equivalent to:
   RA(J2000)  = 01h 03m 10.77s
   Dec(J2000) = -39d 05' 18.0"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 70 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.  We
cannot determine whether the source is fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
2.15e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 7.93e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 56 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 19.6 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
0.01. 

Burst Advocate for this burst is S. T. Holland (Stephen.T.Holland 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: GRB100625A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10885
SUBJECT: GRB100625A : MOA optical upper limit 
DATE:    10/06/25 21:19:35 GMT
FROM:    Suzuki Daisuke at MOA-II  <dsuke@stelab.nagoya-u.ac.jp>

D. Suzuki, F. Hayashi, S. Kobara, T. Sako, H.Naito, K. Omori (STE Lab, Nagoya Univ.)
on behalf of the MOA Collaboration  report:

We searched for an optical afterglow of GRB 100625A (GCN 10884, S. T. Holland et al.)
starting from 18:49 UT on 2010 June 25th (17 minutes after the BAT trigger)
with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand.
In a single image of a 60sec exposure with a wide-band Red filter (center 
wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object
within the error circle of the Swift XRT source position (GCN 10884).
A 3 sigma upper limit is set in the I magnitude at 22.77 mag.   

This photometry was done by using the DoPhot and calibrated against the 
USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.


GRB_name: GRB100625A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10886
SUBJECT: GRB 100625A: Enhanced Swift-XRT position
DATE:    10/06/26 04:51:36 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 646 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 100625A, 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 = 15.79574, -39.08842 which is equivalent
to:

RA (J2000): 01h 03m 10.98s
Dec (J2000): -39d 05' 18.3"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100625A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10887
SUBJECT: GRB 100625A: Gemini candidate afterglow
DATE:    10/06/26 08:21:14 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick) and N.R. Tanvir (U. Leicester) report on behalf of
a larger collaboration:

"We observed the location of the short-hard GRB 100625A (Holland et
al. GCN 10884) using Gemini-South and GMOS under poor conditions
beginning at 06:50 UT. A total exposure time of 600s was obtained in 
the r-band.

Within the refined XRT localisation (Goad et al. GCN 10886) we find
a single source with r~23 (photometric calibration preliminary).
The location of the source is:

RA(J2000): 01:03:10.9 4
DEC(J2000): -39:05:18.7

with an error of approximately 0.5" in each axis. We suggest this
may be the afterglow of GRB 100625A, however, given the poor seeing
(2.5") we cannot distinguish between an afterglow or underlying host
galaxy.

Further observations are planned.

We thank the staff of Gemini South, in particular Fredrik Rantakyro,
for their assistance with these observations."


GRB_name: GRB100625A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10888
SUBJECT: GRB 100625A: Swift-XRT Team refined analysis
DATE:    10/06/26 08:34:27 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

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

We have analysed 16 ks of XRT data for GRB 100625A (Holland et al. GCN Circ. 
10884), from 61 s to 35.4 ks 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 10886).

The light curve can be modelled with a power-law decay with a decay index 
of alpha=1.34 (+0.44, -0.26), with a small flare in the first orbit of 
data.

A spectrum formed from the PC mode data can be fitted with an absorbed 
power-law with a photon spectral index of 2.34 (+0.31, -0.23). The best-fitting 
absorption column is consistent with the Galactic value of 2.1 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 3.2 x 10^-11 (3.6 x 10^-11) erg 
cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 
1.34, the count rate at T+24 hours will be 1.1 x 10^-4 count s^-1, 
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.5 x 10^-15 
(3.9 x 10^-15) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at 
http://www.swift.ac.uk/xrt_products/00425647.

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


GRB_name: GRB100625A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10889
SUBJECT: GRB 100625A : IRSF/SIRIUS NIR upper limit
DATE:    10/06/26 10:13:17 GMT
FROM:    Hiroyuki Naito at Nagoya U  <naito@stelab.nagoya-u.ac.jp>

H. Naito, T. Sako, D. Suzuki, S. Kobara and K. Omori (Nagoya Univ.) on  
behalf of the MOA Collaboration, T. Nagayama, M. Kurita (Nagoya Univ.)  
and N. Oi (The Graduate University for Advanced Studies/NAOJ) on  
behalf of the IRSF Collabration report:

We searched for a NIR afterglow of the short GRB 100625A (S. T.  
Holland et al., GCN 10884) starting from 03:07:07 UT on 2010 June 26  
with the SIRIUS on the IRSF 1.4m telescope at SAAO in South Africa. In  
images of a 20 min exposure with J, H and Ks filter, we did not find  
any object within the error circle of the Swift XRT source position  
(M. R. Goad et al., GCN 10886) and at the location of the Gemini  
source (A. J. Levan and N. R. Tanvir, GCN 10887).

A 3 sigma upper limits are the followings.

J > 19.37
H > 18.88
K > 18.02

This photometry was done by using the DoPhot and calibrated against  
the 2MASS cataloged stars.


GRB_name: GRB100625A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10890
SUBJECT: Konus-Wind observation of GRB 100625A
DATE:    10/06/26 10:28:51 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The short hard GRB 100625A (Swift-BAT trigger #425647:
Holland et al., GCN 10884) triggered Konus-Wind
at T0=66747.799 s UT (18:32:27.799).

The burst light curve consists of two main peaks separated
by ~100 ms, with a total duration of the burst of ~350 ms.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100625_T66747/

As observed by Konus-Wind the burst
had a fluence of 0.83(+/-0.15)x10-6 erg/cm2,
and a 16-ms peak flux measured from T0 + 0.128s
of 8.1(+/-1.5)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+0.192 s) is well fit
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 = -0.1(-0.5, +0.6),
and Ep = 414(-78,+128) keV,
chi2 = 18/18 dof.

This spectrum is equally well fit
in the same range by the GRB (Band) model, for which:
the low-energy photon index alpha = +0.1 (+/-0.6),
the high energy photon index beta = -2.6 ( <-1.9 ),
the peak energy Ep = 371(-100,+135) keV,
chi2 = 17/17 dof.

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


GRB_name: GRB100625A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10891
SUBJECT: GRB 100625A: Swift-BAT refined analysis
DATE:    10/06/26 14:34:54 GMT
FROM:    Michael Stamatikos at OSU/GSFC  <michael.stamatikos-1@nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), 
E. E. Fenimore (LANL), N. Gehrels (GSFC), S. T. Holland (CRESST/USRA/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 (OSU/NASA/GSFC), J. Tueller (GSFC), T. N. Ukwatta (GWU) 
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+500 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100625A (trigger #425647)
(Holland, et al., GCN Circ. 10884).  The BAT ground-calculated position is
RA, Dec = 15.796, -39.091 deg which is 
   RA(J2000)  =  01h 03m 11.1s 
   Dec(J2000) = -39d 05' 29.3" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted light curve shows two overlapping peaks starting at ~T-0.1 sec,
peaking at ~T+0.1 and T+0.2 sec, and ending at ~T+0.3 sec.  There is a weak soft
tail out to ~T+30 sec.  T90 (15-350 keV) is 0.33 +- 0.03 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-0.1 to T+0.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
0.90 +- 0.10.  The fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-07 erg/cm2.
The 1-sec peak photon flux measured from T-0.37 sec in the 15-150 keV band
is 2.6 +- 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/425647/BA/


GRB_name: GRB100625A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10892
SUBJECT: GRB 100625A: Swift/UVOT Upper Limits
DATE:    10/06/26 17:38:46 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W. Landsman (NASA/GSFC/Adnet) and S. Holland ((CRESST/USRA/GSFC) report 
on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100625A 
56s after the BAT trigger (Holland et al., GCN Circ. 10884). No optical 
afterglow consistent with the enhanced  XRT position (Page et al., GCN 
Circ. 10888) or the Gemini-South candidate afterglow position (Levan et 
al. GCN Circ. 10887) is detected in the initial UVOT exposures. 
Preliminary 3-sigma upper limits using the UVOT photometric system 
(Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC) 
and subsequent exposures are:


Filter   T_start(s)  T_stop(s)  Exp(s)   Mag
-----------------------------------------------
white     87          206        147 >21.2 (FC)
u        269          519        246 >20.2 (FC)

white     87        11552        785 >22.6
v        598         5951        412 >20.3
b        524        10640       1117 >21.9
u        269         6522        614 >20.5
w1      4725         6362        393 >20.6
m2      4520         6157        393 >20.5
w2      4111        12302       1125 >21.5


The values quoted above are not corrected for the Galactic extinction 
due to the reddening of E(B-V) = 0.012 in the direction of the burst 
(Schlegel et al. 1998).


GRB_name: GRB100614A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10893
SUBJECT: GRB 100614A: CrAO optical limit
DATE:    10/06/26 19:55:21 GMT
FROM:    Vasilij Rumjantsev at CrAO  <rum@crao.crimea.ua>

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

We observed the field of the Swift GRB 100614A (Stratta  et al. GCN 10837)
with AZT-11 telescope of  CrAO between (UT) June, 15  19:18 -- 20:19.
We do not detect any source in enhanced XRT error circle (Osborne et al.,
GCN 10849).
The photometry based on USNO-B1.0 star 1392-0274963 (RA(J2000) = 17:34:02.22
Dec(J2000)= +49:14:58.3 )  assuming  R=17.73  is following:

T0+      Filter,   Exposure,  mag. UL
(mid, d)              (s)

0.9236     R       20x180    > 21.9


GRB_name: GRB100628A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10895
SUBJECT: GRB 100628A: Swift detection of a short hard burst
DATE:    10/06/28 08:48:19 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

S. Immler (CRESST/GSFC/UMD), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), S. Campana (INAF-OAB),
C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC),
V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB),
P. T. O'Brien (U Leicester), C. Pagani (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL),
P. Romano (INAF-IASFPA), M. H. Siegel (PSU),
M. Stamatikos (OSU/NASA/GSFC) and R. L. C. Starling (U Leicester)
report on behalf of the Swift Team:

At 08:16:40 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100628A (trigger=426114).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 225.968, -31.661 which is 
   RA(J2000)  =  15h 03m 52s
   Dec(J2000) = -31d 39' 38"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows single hard spike
with a duration of about 0.1 sec.  The peak count rate
was ~4500 counts/sec (15-350 keV), at ~0 sec after the trigger.  We believe
this trigger to be real because the count rate is above the cosmic ray
shower level, the duration is longer than produced by a shower, and
the signal is distributed across the detector plane. 

The XRT began observing the field at 08:18:06.8 UT, 86.0 seconds after
the BAT trigger. No source was detected in the promptly available XRT
data. We are waiting for the full dataset to detect and localise the
XRT counterpart. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 89 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
0.17. 

Burst Advocate for this burst is S. Immler (immler 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: GRB100628A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10896
SUBJECT: GRB 100628A: Swift-BAT refined analysis
DATE:    10/06/28 16:16:49 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), T. Sakamoto (GSFC/UMBC),
W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), S. Immler (CRESST/GSFC/UMD),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), G. Sato (ISAS), M. Stamatikos (ORAU/GSFC),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+577 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100628A (trigger #426114)
(Immler, et al., GCN Circ. 10895).  The BAT ground-calculated position is
RA, Dec = 225.943, -31.653 deg, which is 
   RA(J2000)  =  15h 03m 46.2s 
   Dec(J2000) = -31d 39' 10.2" 
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 70%.
 
The mask-weighted light curve shows two overlapping peaks starting at
~T_zero to ~T+0.04 sec.  T90 (15-350 keV) is 0.036 +- 0.009 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-0.004 to T+0.036 sec is equally well fit
by the exponential cutof powerlaw and a blackbody:
Exponential cutoff: photon index -2.67 +1.8/-3.7, and Epeak of 74.1 +- 11.4 keV
(chi squared 60.5 for 56 d.o.f.).  Blackbody: kT = 19.8 +- 2.9
(chi squared 61.0 for 57 d.o.f.).

The total fluence in the 15-150 keV band is 2.5 +- 0.5 x 10^-8 erg/cm2 and
the 1-sec peak flux measured from T-0.48 sec in the 15-150 keV band is
0.5 +- 0.1 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.26 +- 0.25 (chi squared 81.3 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/426114/BA/


GRB_name: GRB100625A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10897
SUBJECT: GRB 100625A:  Magellan near-IR Observations
DATE:    10/06/28 16:41:19 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger, R. Chornock, W. Fong (Harvard), W. Krzeminski (LCO), and G. 
Anglada (Carnegie/DTM) report:

"We observed the location of the short GRB 100625A (GCN 10884) using the 
PANIC infrared imager on the Magellan/Baade 6.5-m telescope on 2010 June 
27.39 UT (38.9 hours after the burst).  A total of 1.75 hours were 
obtained in J-band in good seeing conditions (0.75 arcsec).  Within the 
refined XRT error circle (GCN 10886) we detect a single object, 
coincident with the optical source detected by Levan et al. with Gemini 
about 12.3 hours after the burst (GCN 10887).  In our combined image the 
object appears to be mildly extended.  Given the continued detection of 
the object about 27 hours after the initial Gemini detection (with r~23 
mag), and its extended nature, we consider this source to be a potential 
host galaxy."


GRB_name: GRB100628A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10898
SUBJECT: GRB 100628A: INTEGRAL SPI-ACS light curve
DATE:    10/06/28 18:45:54 GMT
FROM:    Volker Beckmann at APC  <beckmann@apc.univ-paris7.fr>

V. Beckmann (APC), M. Beck, C. Ferrigno, V. Savchenko, Ievgen Vovk (ISDC), J.
Borkowski (CAMK/Torun), D. Gtz (CEA/Saclay), S. Mereghetti
(INAF/IASF-Milano), and A. von Kienlin (MPE) report on behalf of the
INTEGRAL SPI-ACS GRB team:

GRB 100628A, detected in Swift/BAT data (Immler et al., GCN 10895;
Barthelmy et al., GCN 10896), is detectable also in the data of the  
SPI Anti-Coincidence System (ACS) on-board INTEGRAL. The SPI-ACS light  
curve shows the peak of the burst at 2010-06-28T08:16:41 with a  
maximum count-rate of ~600
counts/50msec. The duration of the GRB is about 0.05 seconds.

The SPI-ACS light curves are available (both as images and data files)
at http://isdc.unige.ch/Soft/ibas/ibas_acs_web.cgi

The light curves, binned at 50 ms, are derived from 91 independent
detectors with different lower energy thresholds (mainly between 50 keV
and 150 keV) and an upper threshold at about 100 MeV. The ACS response
varies as a function of the GRB incident angle. For these reasons we
caution that the count rates cannot be easily translated into physical
flux units. It is not possible to localize a burst based on the SPI-ACS data.

----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.


GRB_name: GRB100628A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10899
SUBJECT: GRB 100628A: Swift XRT detection of a possible X-ray afterglow 
DATE:    10/06/28 20:24:02 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C.  Starling (U. Leicester) and S. Immler (CRESST/GSFC/UMD) report on 
behalf of the Swift-XRT team:

We have analysed 8.7 ks of XRT data for GRB 100628A (Immler  et al. GCN
Circ. 10895), from 93 s to 18.8 ks after the  BAT trigger. The data are
entirely in Photon Counting (PC) mode. A source is detected at the 3-sigma 
confidence level within the BAT refined error circle (Barthelmy et al. GCN 
Circ. 10896) at the position:
RA (J2000)  = 15 03 52.95
Dec (J2000) = -31 39 41.7
with an error of 5.2 arcsec (radius, 90% containment). This is 91.8 arcsec 
from the BAT refined position.

The possible source has a count rate of 0.0023+/-0.0007 count/s. We cannot 
determine whether the source is fading at this time.

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


GRB_name: GRB100628A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10900
SUBJECT: GRB100628A: RTT150 optical observations
DATE:    10/06/28 22:25:30 GMT
FROM:    Rodion Burenin at IKI, Moscow  <rodion@hea.iki.rssi.ru>

R. Burenin, G. Khorunzhev, S. Sazonov (IKI), I. Khamitov (TUG), 
M. Pavlinsky, R. Sunyaev (IKI), I. Bikmaev, N. Sakhibullin (KSU/AST),
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)

report:

The field of GRB100628A (Immler et al., GCN 10895) was observed with
Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National
Observatory, Turkey). We obtained a serie of Rc images, centered at June 28,
19:10 UT, i.e. approximately 11 hours after the burst. 

We do not find any new optical source inside the XRT error circle of
possible X-ray afterglow (Starling et al., GCN 10899) as compared to DSS red
plate.


GRB_name: GRB100628A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10901
SUBJECT: GRB 100628A: Swift/UVOT Upper Limits
DATE:    10/06/28 22:48:13 GMT
FROM:    Stefan Immler at NASA/GSFC  <stefan.m.immler@nasa.gov>

S. Immler (CRESST/GSFC/UMD) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100628A
90 s after the BAT trigger (Immler et al., GCN Circ. 10895). No optical
afterglow consistent with the XRT position (Starling et al., GCN Circ.
10899) is detected in the initial UVOT exposures. Preliminary 3-sigma
upper limits using the UVOT photometric system (Poole et al. 2008,
MNRAS, 383, 627) for the first finding chart (FC) exposure and subsequent
exposures are:

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

white_FC            90          239          147         >20.2
u_FC               302          551          246         >19.4
white               90        11409         1498         >21.4
v                  631        12968         1099         >19.5
b                  557         7133          471         >20.1
u                  302         6928          697         >20.2
w1                 680         6722          471         >19.6
m2                4882         6517          393         >19.3
w2                 607        12315         1176         >20.3


The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.17 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100628A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10902
SUBJECT: GRB 100628A:  Magellan near-IR observations
DATE:    10/06/29 03:31:31 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard), T. Guver (U. of Arizona), W. Fong, R. Chornock
(Harvard) report:

"We observed the location of the potential X-ray afterglow (GCN 18099)
of the short GRB 100628A (GCN 10895) with the PANIC infrared imager on
the Magellan/Baade 6.5-m telescope on 2010 June 29.07 UT (17.4 hours
after the burst).  A total of 27 min on source were obtained in the
J-band with seeing of about 1.1 arcsec.  We do not detect any sources
within the XRT error circle to a limit of about J>20.6 mag (Vega;
5-sigma).

However, surrounding the XRT error circle are several apparent
galaxies located at the following positions (J2000; astrometry
relative to USNO-B with rms of about 0.25" in each coordinate):

G1: RA = 15:03:53.34, DEC = -31:39:50.2
G2: RA = 15:03:53.61, DEC = -31:39:37.6
G3: RA = 15:03:52.43, DEC = -31:39:44.2
G4: RA = 15:03:52.85, DEC = -31:39:36.9
G5: RA = 15:03:52.85, DEC = -31:39:35.8

A finder marking the location of these objects relative to the XRT
error circle is available from:

http://www.cfa.harvard.edu/~eberger/grb100628_panic_2010June29.jpg

Additional observations are planned to check for variability in any of
the sources."


GRB_name: GRB090709A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10903
SUBJECT: GRB 090709A: Host galaxy detection
DATE:    10/06/29 04:44:26 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, S. B. Cenko, and J. S. Bloom (UC Berkeley) report:

We observed the field of GRB 090709A (Morris et al., GCN 9625) using 
NIRI on Gemini-North on the night of 2010-06-23 between 11:54 and 14:46 
UT, under good conditions.  Our co-added stack contains a total of 146 
images of 60 seconds each (2.43 hours of imaging) in the K' filter.  The 
3-sigma limiting magnitude of the stack is K' ~ 23.7.  (Calibration of 
the field was established relative to several 2MASS stars in the image.)

Matching our image directly to early-time PAIRITEL imaging (Morgan et 
al., GCN 9635), we detect a faint, extended source slightly offset (0.6 
arcsec) from the position of the IR afterglow.  The orientation of the 
offset is along the apparent direction of extension of the source (E-W). 
   Aperture photometry within a 1.0 arcsec aperture centered on the 
object gives a magnitude of K' = 22.0 +/- 0.2 mag.  The chance 
probability for this alignment is approximately one percent (Bloom et 
al. 2002, AJ 123:1111, Djorgovski et al. 1995, ApJL 438:L13).

We therefore associate this object with the host galaxy of GRB 090709A. 
   The detection of a host galaxy confirms the extragalactic, 
cosmological nature of this event (de Luca et al. 2010, MNRAS 402:1870; 
Cenko et al. 2010, AJ 140:224).  We note that deep optical imaging of 
this field by the GTC (Castro-Tirado et al., GCN 9655) detected no 
object at this position to a limit of i' > 25.5, suggesting that the 
host galaxy may be internally dust-reddened.  The infrared afterglow 
also showed evidence of strong reddening (Cenko et al. 2010), and 
foreground extinction in this direction is low; E(B-V) = 0.09 mag. 
Additional imaging is encouraged to test this hypothesis.

An image of the field is posted to:
http://lyra.berkeley.edu/~dperley/090709a/090709a_niri.png

We are happy to thank Marie Lemoine-Busserolle, Matthew Dillman, and 
Andrew Stephens for their support during our classical NIRI run.


GRB_name: GRB100628A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10904
SUBJECT: GRB100628A : MOA optical upper limit
DATE:    10/06/29 05:31:35 GMT
FROM:    Suzuki Daisuke at MOA-II  <dsuke@stelab.nagoya-u.ac.jp>

D. Suzuki, K. Omori, F. Hayashi, S. Kobara, H. Naito and T. Sako (STE Lab. , Nagoya Univ.)
on behalf of the MOA Collaboration repot :

We searched for an optical afterglow of GRB100628A (GCN 10895, S. Immler et al.)
starting from 08:16:43 UT on 2010 June 28 ( 3 minutes after the burst) 
with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand.
In a single image of a 300 sec exposure with a wideband Red filter (center 
wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object
within the error circle of the Swift XRT source position (GCN 10899, R.L.C. Starling et al.).
A 3 sigma upper limit is set in the I magnitude at 22.7 mag.   

This photometry was done by using the DoPhot and calibrated against the 
USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.


GRB_name: GRB100625A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10905
SUBJECT: GRB 100625A Gemini-South 2nd epoch imaging
DATE:    10/06/29 11:36:34 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

N.R. Tanvir (U. Leicester) and A.J. Levan (U. Warwick) report on
behalf of a larger collaboration:

We re-observed the location of the short-hard GRB 100625A using
GMOS on Gemini-South on 2010-06-28 beginning at 09:21 UT
(approximately 63 hours post-burst).

The source we previously identified within the XRT error circle
(Levan et al. GCN 10887) is still detected with no obvious fading.
We therefore concur with Berger et al. (GCN 10897) that this source,
which is marginally extended, is a good candidate to be the host
galaxy of the GRB.

We thank the staff of Gemini South, in particular Fredrik Rantakyro,
for their assistance with these observations.

[GCN OPS NOTE(29jun10): Per author's request, the "North" in the Subject-line
was changed to "South".]


GRB_name: GRB100625A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10906
SUBJECT: GRB100625A: GROND confirmation of constant source
DATE:    10/06/29 14:01:16 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 100625A: GROND confirmation of constant source

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

We observed the field of the short-hard GRB 100625A, discovered by
SWIFT(Holland et al., GCN 10884), simultaneously in g'r'i'z'JHK with GROND
(Greiner et al.2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope
at La Silla Observatory (Chile).

First epoch observations started at 06:13 UT on June 26, 10.7 hours
after the GRB trigger, lasting for about 1 hour and done at high air mass.
We took a second epoch starting at 09:29 UT on June 27 (~38 hrs after the
trigger), lasting also for about 1 hour and done at seeing of ~ 2''.

Within the enhanced XRT-position error circle (Good et al., GCN 10886)
we detect a faint object at a position compatible with the Gemini-South
candidate afterglow (Levan & Tanvir, GCN 10887).

Based on stacked images with a total integration time of 49.6 min in
g'r'i'z' and 40 min for JHK for each epoch, preliminary AB magnitudes
(calibrated with GROND zero points) show that within the errors the object
is constant between our two epochs.

As suggested by the Magellan observations (Berger et al., GCN 10897) our
results also point to the detection of a possible host galaxy.


GRB_name: GRB100628A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10907
SUBJECT: GRB 100628A: Swift XRT refined position
DATE:    10/06/29 14:16:43 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C. Starling, A.P. Beardmore (U. Leicester) and S. Immler 
(CRESST/GSFC/UMD) report on behalf of the Swift-XRT team:

We have analysed further Swift XRT data totalling 24.77 ks of exposure for GRB 
100628A (Immler et al. GCN Circ. 10895), from 93 s to 80.75 ks after the BAT 
trigger.
The source reported in Starling & Immler (GCN Circ. 10899) is still detected, 
but we cannot confirm any fading at this time. We report a
significantly revised position, incorporating the new data and using an
exposure map corrected psf-centroid fitting method, of
  RA (J2000)  = 15 03 53.52
  Dec (J2000) = -31 39 49.7
with an error of 4.7 arcsec (radius, 90% containment).

This is still within the BAT refined error circle (Barthelmy et al.
GCN Circ. 10896), 10.8 arcsec from the initial XRT position.
This position is 2.3 arcsec from the galaxy G1 reported in Berger et al.
(GCN Circ. 10902).

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


GRB_name: GRB100628A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10908
SUBJECT: GRB 100628A: Coincidence of source "G1" with revised XRT error circle
DATE:    10/06/29 14:23:29 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) reports:

"Inspection of our PANIC J-band image from 2010 June 29.07 UT (GCN 
10902) at the location of the revised XRT error circle (GCN 10907)
reveals that the galaxy designated "G1" is now located within the
error circle, about 2.4 arcsec from its center.  A revised finder is
available from:

http://www.cfa.harvard.edu/~eberger/grb100628_panic_2010June29_v2.jpg

Additional observations are planned to check for variability."


GRB_name: GRB100628A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10909
SUBJECT: GRB 100628A: Gemini North Observations
DATE:    10/06/29 17:46:37 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick), N.R. Tanvir, K. Wiersema (U. Leicester),
S.B. Cenko (UC Berkeley) report on behalf of a larger collaboration:

"We obtained two epochs of observations of GRB 100628A (Immler et
al. GCN 10895) with Gemini-North. The first was obtained starting
at 28 Jun, 08:59 UT, approximately 43 minutes after the burst, with
a second obtained on 29 Jun 05:50 UT, ~21.5 hours after the burst.
A total of 1200s of exposure time were obtained in the i-band. Our
images covers ~90% of the BAT refined error circle (Barthelmy et
al GCN 10896), including the position of the candidate X-ray afterglow
identified by Starling et al. (GCN 10899; 10907).

Digital image subtraction performed between the two epochs does not
reveal any candidate variable sources between the two epochs, to
an approximate limiting magnitude of i~24. In particular, we do not
find any evidence for variability in any of the galaxies identified
by Berger et al. (GCN 10902) surrounding the XRT location,
including G1, which now lies within the XRT error circle
(Starling et al. GCN 10907; Berger et al. GCN 10908)

We also note the presence of two, apparently point like sources
lying within the refined XRT error circle, at locations of

S1:
RA(J2000) 15:03:53.45
DEC(J2000) -31:39:54.2

S2:
RA(J2000)  15:03:53.73
DEC(J2000) -31:39:48.4

Both are unresolved at the resolution of our observations, but
neither show apparent variability between the two epochs.

An image, showing the field as observed by Gemini-North can be found
at

http://www.star.le.ac.uk/~anl/100628A

We thank the staff of Gemini-North for their assistance with these
observations."


GRB_name: GRB100628A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10910
SUBJECT: GRB 100628A: GROND optical/NIR observations of the host candidate
DATE:    10/06/29 22:04:47 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

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

We observed the field of GRB 100628A (Immler et al., GCN 10895)
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120,
405) mounted at the 2.2 m MPI/ESO telescope at La Silla
Observatory (Chile).

Observations started at 01:24 UT on June 29, 17.1 hours after the GRB
trigger, and continued for 1.5 hours.

In stacked images of 75 min total integration time in g'r'i'z' and 60
minutes in JHK we detect the possible host galaxy candidate G1 first
noted in Berger et al., GCN #10902 and Berger, GCN #10908 inside the
refined XRT position (Starling et al. GCN 10907) in all filters.

Preliminary photometry yields the following AB magnitudes:

g' = 22.8 +- 0.2
r' = 21.5 +- 0.1
i' = 20.6 +- 0.1
z' = 20.0 +- 0.1
J  = 19.4 +- 0.1
H  = 19.0 +- 0.1
K  = 18.6 +- 0.1

calibrated against the GROND zeropoints and 2MASS field stars, and
uncorrected for the expected mild foreground reddening in the direction
of the burst of E(B-V) = 0.17 (Schlegel et al. 1998).

Galaxy spectral template fitting using the publically available Lephare
code (Arnouts & Ilbert 2009,
http://www.cfht.hawaii.edu/~arnouts/LEPHARE/cfht_lephare/lephare.html)
provides good fits of this very red spectral energy distribution with
starburst or late type galaxies. In this interpretation, a photometric
redshift of z=0.67 (+0.34, -0.12) is indicated. We caution that the error
might be underestimated due to the missing photometric calibration in the
g'r'i'z' bands. We note, however, that at this redshift the absolute
magnitude would be rather bright, M_B ~ -22 mag.


GRB_name: GRB100628A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10911
SUBJECT: GRB 100628A: Second epoch of Magellan near-IR observations
DATE:    10/06/30 03:09:37 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard), T. Guver (U. of Arizona), W. Fong, R. Chornock
(Harvard) report:

"We re-observed the location of the potential X-ray afterglow (GCNs
18099, 10907) of the short GRB 100628A (GCN 10895) with the PANIC
infrared imager on the Magellan/Baade 6.5-m telescope on 2010 June
29.98 UT (39.2 hours after the burst and 21.8 hours after our previous
observation: GCN 10902).  A total of 27 min on source were obtained in
the J-band with seeing of about 0.5 arcsec.  Digital image subtraction
of the two epochs does not reveal any variable sources within the XRT
error circle or in coincidence with the galaxy "G1" to a 5-sigma limit
of J=21.6 mag at 17.2 hours after the burst.  This result supports the 
conclusions of Levan et al. (GCN 10909)."


GRB_name: GRB100625A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10912
SUBJECT: GRB 100625A: Fermi GBM detection
DATE:    10/06/30 12:55:57 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 18:32:28.47 UT on 25 June 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100625A (trigger 299183550 / 100625773).
which was also detected by the SWIFT-BAT(Holland et al. 2008, GCN 10884)
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 125 degrees.

The GBM light curve shows of 2 closely spaced narrow pulses
with a duration (T90) of about 0.32 s (50-300 keV).
The time-averaged spectrum from T0-0.128 s to T0+0.192 s is
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.64 +0.12/-0.11 and
the cutoff energy, parameterized as Epeak, is 509.2 +77.5/-61.5 keV

(C-stat value 710 for 609 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.32 +/- 0.05)E-06 erg/cm^2. The 0.064-sec peak photon flux measured
starting from T0-0.128 s in the 8-1000 keV band
is 15.09 +/- 0.59 ph/s/cm^2.

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


GRB_name: GRB100213B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10913
SUBJECT: GRB 100213B: Detection of Fading Optical Afterglow
DATE:    10/06/30 23:03:00 GMT
FROM:    Jules Halpern at Columbia U.  <jules@astro.columbia.edu>

Y. Li, J. Weston, X. Fernandez, A. Brown, J. H. Yoon, A. P. S. Crotts,
and J. P. Halpern (Columbia U.) report on behalf of the graduate
Observational Astronomy class:

"We obtained R-band images of the field of Swift GRB 100213B (Vetere et al.,
GCN 10412) on two consecutive, photometric nights using the MDM 1.3m
telescope, for total exposure times of 30 and 40 minutes, respectively.
Within 3.8" of the enhanced Swift XRT afterglow position (of 90% confidence
radius 3.5", Evans, GCN 10423), we find a fading object at

      (J2000) R.A. = 08h 17m 07.94s, Decl. = +43d 26' 54.94"

with positional uncertainty ~0.5", and the following magnitudes:

    ----------------------------------------------------------
     Date(UT)  Mid-time(UT) t-t0(hr)  Exp(min)      R(mag)
    ----------------------------------------------------------
     Feb. 14      03:44        4.8       30      22.00+/-0.14
     Feb. 15      03:35       28.6       40      23.01+/-0.24
    ----------------------------------------------------------

Magnitudes are referenced to Landolt (1992) standard stars, and are not
corrected for Galactic extinction.

The position of the afterglow coincides with the R ~ 21.5 object detected by
Malesani et al. (GCN 10413) 19 minutes after the GRB, and whose redshift
z = 0.604 was measured by Cucchiara et al. (GCN 10422). We conclude that the
observed variability and positional coincidence with an emission-line object
establishes the optical afterglow and host galaxy redshift of GRB 100213B.
Further observations of the host galaxy are encouraged.

MDM images of the field are posted at

http://www.astro.columbia.edu/~jules/grb/100213b/

This message may be cited."


GRB_name: GRB100615A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10915
SUBJECT: GRB 100615A: Chandra X-ray ToO Observation
DATE:    10/07/01 20:58:13 GMT
FROM:    Nat Butler at UC berkeley  <natxbutler@gmail.com>

N. R. Butler, D. A. Perley, S. B. Cenko, J. S. Bloom (UC Berkeley), A.
J. Levan (U. Warwick), and N. R. Tanvir (U. Leicester) report on
behalf of a larger collaboration:

Beginning 2010/06/15 01:59 UT (6.1 days post burst) and for a period
of 14.8 ksec (livetime), Chandra targeted the field of the optically
dark GRB 100615A (D'Elia et al. 2010, GCN 10841; Foley et al. 2010,
GCN 10851) with ACIS-S under Director's Discretionary Time.  The X-ray
afterglow is well detected (210 cts, 0.5-8 keV) at a position
consistent with that
of the Swift GRB and afterglow (GCN 10841; Goad et al. 2010, GCN
10848). We find:

RA, Dec (J2000) = 11:48:49.34, -19:28:52.0 +/- 0.6"

The counts spectrum can be modelled by an absorbed powerlaw, with
photon index Gamma = 2.0+/-0.5 (Cash/nu = 11.2/17).  The unabsorbed
flux is 3.2^{+1.4}_{-0.7} x 10^{-13} erg cm^(-2) s^(-1) (0.5-8 keV).

There is 6-sigma significant evidence (Delta Cash = 32.4 for 1
additional degree of freedom) for a large N_H column 1.0^{+0.4}_{-0.3}
x 10^22 cm^(-2) (z=0) in excess of the Galactic value (3.3 x10^20
cm^(-2); Kalberla et al. 2005).  This is in agreement with the XRT
analyses (Margutti et al. 2010, GCN 10847) and further indicates that
GRB 100615A
is likely a highly extinguished event (see also, Cenko et al. 2010, GCN 10861).

All uncertainties above are 90% confidence.

We thank Harvey Tananbaum and the CXO team for permitting and rapidly
conducting this observation.  This message can be cited.


GRB_name: GRB100702A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10916
SUBJECT: GRB 100702A: Swift detection of a short burst
DATE:    10/07/02 01:23:20 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

M. H. Siegel (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
J. M. Gelbord (PSU), D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), D. M. Palmer (LANL) and T. N. Ukwatta (GSFC/GWU)
report on behalf of the Swift Team:

At 01:03:47 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100702A (trigger=426438).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 245.702, -56.538 which is 
   RA(J2000) = 16h 22m 49s
   Dec(J2000) = -56d 32' 15"
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 0.3 sec.  The peak count rate
was ~11000 counts/sec (15-350 keV), at ~0.2 sec after the trigger. 

The XRT began observing the field at 01:05:21.1 UT, 93.9 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
245.6969, -56.5316 which is equivalent to:
   RA(J2000)  = 16h 22m 47.26s
   Dec(J2000) = -56d 31' 53.8"
with an uncertainty of 2.4 arcseconds (radius, 90% containment). This
location is 24 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
2.84e+21 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 9.31e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 101 seconds after the BAT trigger. The 2.7'x2.7'
sub-image covers 100% of the XRT error circle. A known source from the
DSS is within the XRT error circle. However, because of the density of
catalogued stars, further  analysis is required to determine if this
is the GRB host, afterglow or an unrelated background source. The
coverage of the XRT 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. Because of the density of
catalogued  stars, further analysis is required to report an upper
limit for any afterglow  in the region. No correction has been made
for the large, but uncertain  extinction expected. 

Burst Advocate for this burst is M. H. Siegel (siegel 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: GRB100702A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10917
SUBJECT: GRB 100702: ROTSE-III Optical Limits
DATE:    10/07/02 01:44:13 GMT
FROM:    Heather Flewelling at IfA/Hawaii  <flewelling.heather@gmail.com>

 H. Flewelling (IfA/Hawaii), W. Zheng (U Mich), S. B. Pandey (U Mich), W.
Rujopakarn (Steward), report on behalf of the ROTSE collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, responded
to GRB 100702 (Swift trigger 426438; M. H. Siegel, GCN 10916), producing
images beginning 7.7 s after the GCN notice time. An automated response took
the first image at 01:04:06.7 UT, 19.5 s after the burst, under fair
conditions. We took 10 5-sec, 10 20-sec and 40 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 or the XRT error circle, for both single
images and coadding into sets of 10; however, we are limited as the field is
severely crowded. Individual images have limiting magnitudes ranging from
15.6-15.9; we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
01:04:06.7   01:05:22.8        76     16.1           19.5       Y

01:20:08.4   01:24:48.5       280     16.2          981.2       Y


GRB_name: GRB100702A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10918
SUBJECT: GRB 100702A: VLT optical observations
DATE:    10/07/02 04:20:18 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

Daniele Malesani (DARK/NBI), Andrew J. Levan (Univ. Warwick), Johan P. 
U. Fynbo (DARK/NBI), report on behalf of the X-shooter GRB collaboration:

We observed the field of the short GRB 100702A (Siegel et al., GCN 
10916) with the ESO VLT equipped with X-shooter.

In the R-band acquisition image, taken starting on 2010 July 2 at 2:05 
UT (1 hr after the GRB), we detect two pointlike sources within the XRT 
error circle (Siegel et al., GCN 10916):

A: RA = 16:22:47.05, Dec = -56:31:53.3, R = 15.49
B: RA = 16:22:47.27, Dec = -56:31:55.4, R = 17.20

A third object is located just above the XRT circle:

C: RA = 16:22:47.30, Dec = -56:31:50.6, R = 17.25

Photometry was computed against USNO-B1. Sources A and C are clearly 
visible in the DSS, while source B can be barely spotted, blended with 
source A. A finding chart is visible at the following URL:

http://www.astro.ku.dk/~malesani/GRB/100702A/GRB100702A_finder.jpg

A second R-band image was taken 48 minutes after, and none of the above 
mentioned sources vary by more than 0.05 mag during this time span. For 
an afterglow decay proportional to t^-1, a variation of ~0.6 mag would 
be expected.

It is thus likely that none of the above sources is related to the GRB. 
This is not surprising given the moderately crowded field (at Galactic 
latitude b = -5 deg). We note that the glare from the above mentioned 
bright objects makes it difficult to identify faint sources within the 
XRT error circle.

We acknowledge excellent and prompt support from the observing staff at 
Paranal, in particular Christophe Martayan, Andrew Fox, Vincenzo 
Mainieri, Manuel Olivares, Thomas Szeifert, and the visitor observer, 
Nick Cox.


GRB_name: GRB100702A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10919
SUBJECT: GRB 100702A:  Magellan near-IR observations
DATE:    10/07/02 04:37:40 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

W. Fong, E. Berger, and M. Servillat (Harvard) report:

"We observed the location of the short GRB 100702A (GCN 10916) with
the PANIC infrared imager on the Magellan/Baade 6.5-m telescope
starting on 2010 July 2.089 UT (65 min after the burst).  A total of
27 min were obtained in the J-band with seeing of about 0.55 arcsec.
Within the 2.4-arcsec radius XRT error circle we detect one bright
point source and two fainter sources at the following coordinates
(J2000; astrometry relative to the 2MASS catalog):

S1: RA = 16:22:47.23, DEC = -56:31:55.6
S2: RA = 16:22:47.53, DEC = -56:31:54.6
S3: RA = 16:22:47.24, DEC = -56:31:52.2

Source S1 is the same as source "B" in GCN 10918 (Malesani et al.),
while sources S2 and S3 are not detected in their finder.

We note that in 2MASS images of the field source S1 is possibly
blended with the bright star at RA = 16:22:47.01, DEC = -56:31:53.5
(designated source "A" in GCN 10918), while sources S2 and S3 are
below the 2MASS sensitivity threshold.

Additional observations are planned to check for variability of
sources S2 and S3."


GRB_name: GRB100701B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10920
SUBJECT: GRB 100701B: Fermi GBM detection
DATE:    10/07/02 08:50:29 GMT
FROM:    Suzanne Foley at MPE  <sfoley@mpe.mpg.de>

S. Foley (MPE)
reports on behalf of the Fermi GBM Team:

"At 11:45:23.07 UT on 01 July 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100701B (trigger 299677525 / 100701490).

The on-ground calculated location, using the GBM trigger
data, is RA = 45.49, DEC = -3.43 (J2000 degrees,
equivalent to 03 h 02 m, -03 d 26 '), 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 107 degrees.

The GBM light curve consists of at least six main pulses
with a duration (T90) of about 27.5 (+/-0.9) s (8-1000 keV).
The time-averaged spectrum from T0-1.2 s to T0+32.7 s is
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.99 (+/-0.02) and
the cutoff energy, parameterized as Epeak, is 1.85 (+/-0.16) MeV
(CSTAT 695.8 for 360 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(2.86 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.4 s in the 8-1000 keV band
is 22.6 +/- 0.3 ph/s/cm^2.

A Band function fits the spectrum equally well (CSTAT 689.8 for 359 d.o.f.)
with Epeak= 1.48 (+0.19/-0.17) MeV, alpha = -0.95 (+/-0.03) and beta =
-2.47 (+0.18/-0.25) .


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


GRB_name: GRB100702A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10921
SUBJECT: GRB 100702A:  Second epoch of Magellan near-IR observations and afterglow limits
DATE:    10/07/02 13:26:12 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger, W. Fong, and M. Servillat (Harvard) report:

"We re-observed the location of the short GRB 100702A (GCN 10916) with
the PANIC infrared imager on the Magellan/Baade 6.5-m telescope
starting on 2010 July 2.290 UT (4.8 hours after our first observation,
which started 65 min after the burst; GCN 10919).  A total of 27 min
were obtained in the J-band with slightly worse seeing than in our
first epoch, 0.75 arcsec.  Digital image subtraction of the two epochs
using the ISIS package reveals no change in the flux of our
previously-identified sources S1 (source "B" of Malesani et al. GCN
100918), S2, or S3.  No other variable sources are detected within a
45x45 arcsec region centered on the XRT position to a 5-sigma limit of
J>22.1 mag (Vega).

We note, however, that the bright star at RA = 16:22:47.01, DEC = 
-56:31:53.5 (designated source "A" in GCN 10918) strongly contaminates 
the subtracted image over about 1/4 of the XRT error circle."


GRB_name: GRB100702A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10922
SUBJECT: Swift/UVOT observations of GRB100702A
DATE:    10/07/02 13:37:35 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

M. De Pasquale (MSSL-UCL) and M. H. Siegel (PSU) report on behalf of the
Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 100621A 101s
after the BAT trigger (Siegel et al,  GCN 10916). The enhanced XRT error 
circle appears crowded with sources (Malesani et al., GCN  10918, Fong et 
al, GCN 10919) which blend together. There is no clear indication of 
change of optical flux between the first exposures and later ones. The 
preliminary magnitudes and 3-sigma upper limits for the finding chart 
exposures (FC) and summed images for the emission in the XRT enhanced 
error circle are:

Filter         T_start    T_stop     Exp(s)   Magnitude/3-sigma upper 
limit
-------------------------------------------------------------
white (FC)     101        251       147       17.99 +/- 0.07
white          594      10684      1295       17.84 +/- 0.05
  u     (FC)    314        564       246       18.85 +/- 0.17
  u            5020       5151       131       18.96 +/- 0.26
  v            4405      17014       735       16.72 +/- 0.04
  b             570       6306       216       17.79 +/- 0.08
uvw1          4815       5015       196         > 19.60
uvm2          4610       4810       197         > 19.40
uvw2          4200      16457      1432         > 20.85
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected  Galactic
extinction along the line of sight corresponding to E_(B-V) = 0.41 mag. 
All photometry is on the UVOT photometric system described in Poole et al. 
(2008, MNRAS, 383, 627).


GRB_name: GRB100702A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10923
SUBJECT: Swift/UVOT observations of GRB100702A - correction
DATE:    10/07/02 13:54:36 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

M. De Pasquale (MSSL) reports:

"In the text of the GCN circular 10922, Swift/UVOT observations of 
GRB100702A', GRB100621A
is erroneously mentioned. All the data quoted in that circular refer to 
GRB100702A. We
apologize for the mistake".


GRB_name: GRB100702A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10924
SUBJECT: GRB 100702A: Swift XRT refined analysis 
DATE:    10/07/02 15:15:29 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

D. Grupe and M. Siegel (PSU)
report on behalf of the Swift-XRT team:


We have analyzed 3770 s of XRT data for GRB 100702A
(Siegel  et al. GCN Circ. 10916), from 100 s to 9676 s after the
BAT trigger. The data comprise 190 s in Windowed Timing (WT) mode
with the remainder in Photon Counting (PC) mode. The light curve can
be modeled with an initial power-law decay with an index of
alpha=0.65 (+0.37, -0.25), followed by a break at T+185 s to an alpha
of 4.33 (+0.53, -0.24). The afterglow is not detected after the
first orbit.


A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.92 (+0.11, -0.10). The
best-fitting absorption column is  3.6 (+/-0.4) x 10^21 cm^-2, in
excess of the Galactic value of 2.8 x 10^21 cm^-2 (Kalberla et al.
2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.45 x 10^-11 (6.94 x 10^-11) erg
cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00426438.

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


GRB_name: GRB100702A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10926
SUBJECT: GRB 100702A, Swift-BAT refined analysis
DATE:    10/07/02 15:45:04 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <takanori@milkyway.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), D. M. Palmer (LANL), A. M. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. H. Siegel (PSU), 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 BAT GRB 100702A (trigger #426438)
(Siegel, et al., GCN Circ. 10916).  The BAT ground-calculated position is
RA, Dec = 245.693, -56.549 deg which is 
   RA(J2000)  =  16h 22m 46.4s 
   Dec(J2000) = -56d 32' 57.4" 
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 61%.
 
The mask-weighted light curve shows a FRED-like pulse starting at T_zero to 
~T+0.25 sec.  There is a possible weak pulse emission at T-0.25 sec.  
T90 (15-350 keV) is 0.16 +- 0.03 sec (estimated error including systematics).
 
The time-averaged spectrum from T+0.036 to T+0.236 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.54 +- 0.15.  The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-07 erg/cm2.
The 1-sec peak photon flux measured from T-0.36 sec in the 15-150 keV band
is 2.0 +- 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/426438/BA/


GRB_name: GRB100526A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10927
SUBJECT: GRB 100526A: Gemini/NIRI afterglow confirmation and host galaxy
DATE:    10/07/02 22:51:48 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom, and S. B. Cenko (UC Berkeley) report:

We re-observed the field of GRB 100526A (Vetere et al., GCN 10797) with 
NIRI on Gemini-North between 08:30 and 09:00 UT on 2010-06-24 UT.  We 
acquired 27 images of 60 seconds each in K-band.

Comparison to our previous K-band imaging of this field (Perley et al., 
GCN 10806) shows the infrared counterpart to have faded significantly. 
A source is still detected at high significance at the afterglow 
position.  Using the same 2MASS reference star as for our previous 
epoch, we measure a magnitude of:

K = 21.2 +/- 0.2   (t_mid = 27.7 days)

This corresponds to a decay index (t^-alpha) of only alpha~0.5 from our 
previous epoch, which is much slower than expected for a late-time 
afterglow, and suggests that the current epoch is likely host-galaxy 
dominated.

A comparison image is posted to:
http://lyra.berkeley.edu/~dperley/100526a/100526a_niri.png


GRB_name: GRB100615A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10928
SUBJECT: GRB 100615A: Additional Gemini/NIRI observations
DATE:    10/07/02 22:58:46 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom, S. B. Cenko, and N. R. Butler (UC Berkeley) 
report:

We again observed the field of GRB 100615A (D'Elia et al. 2010, GCN 
10841) using NIRI on Gemini-North between 06:06 and 07:03 on 2010-06-24 
UT, at moderately high airmass.  We acquired 45 images of 60 seconds 
each in the K' filter, a significantly deeper integration than our 
previous observation (Cenko et al., GCN 10861).

A faint object is detected slightly west of the latest online 
UVOT-enhanced XRT error circle, with an aperture magnitude of K' = 21.3 
+/- 0.3 mag.  However, the location of this object is not consistent 
with the improved X-ray localization provided by the Chandra 
observations (Butler et al., GCN 10915).

A very faint possible source is visible at the Chandra location, but it 
is not statistically significant (1.5-sigma).  The 3-sigma limit of the 
image is K' > 22.2 mag; forced photometry gives K' = 23.0 +/- 0.8 mag at 
this location.

An image of the field is posted to:
http://lyra.berkeley.edu/~dperley/100615a/100615a_niri.png


GRB_name: GRB100704A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10929
SUBJECT: GRB 100704A: Swift detection of a burst
DATE:    10/07/04 03:54:17 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

D. Grupe (PSU), S. D. Barthelmy (GSFC), J. R. Cummings (NASA/UMBC),
J. M. Gelbord (PSU), C. Gronwall (PSU),
S. T. Holland (CRESST/USRA/GSFC), N. P. M. Kuin (UCL-MSSL),
D. M. Palmer (LANL), M. H. Siegel (PSU) and T. N. Ukwatta (GSFC/GWU)
report on behalf of the Swift Team:

At 03:35:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100704A (trigger=426722).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 133.636, -24.216 which is 
   RA(J2000) = 08h 54m 33s
   Dec(J2000) = -24d 12' 55"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a bright FRED
peak structure with a duration of about 30 sec, followed by further
activity beginning at T+140 s.  The peak count rate
was ~7000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 03:36:34.9 UT, 86.2 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 133.64103,
-24.20306 which is equivalent to:
   RA(J2000)  = 08h 54m 33.85s
   Dec(J2000) = -24d 12' 11.0"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 48 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 (1.05e+21
cm^-2, Kalberla et al. 2005), with an excess column of 2.5
(+1.43/-1.30) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 3.53e-09 erg cm^-2 s^-1 (0.2-10
keV). 


UVOT took a finding chart exposure of 150 seconds with the White filter
starting 96 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 19.6 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
0.17. 




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: GRB100704A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10930
SUBJECT: GRB 100704A: Enhanced Swift-XRT position
DATE:    10/07/04 09:02:06 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 3449 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 100704A, 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 = 133.64132, -24.20269 which is equivalent
to:

RA (J2000): 08h 54m 33.92s
Dec (J2000): -24d 12' 09.7"

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) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100704A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10931
SUBJECT: GRB100704A: MOA optical upper limit
DATE:    10/07/04 09:16:54 GMT
FROM:    Kengo Omori at U.Nagoya/MOA-II  <morisuke@stelab.nagoya-u.ac.jp>

K. Omori, D. Suzuki, S. Kobara, H. Naito and T. Sako (STE Lab., Nagoya Univ.)
on behalf of the MOA Collaboration report:

We searched for an optical afterglow of GRB100704A (GCN 10929, D. Grupe et al.)
starting from 06:59:33 UT on 2010 July 4 (204 minutes after the burst)
with the MOA-II 1.8m telescope at Mt. John observatory in New Zealand.
In a single image of a 180 sec exposure with a wideband Red filter (center
wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object
within the error circle of the Swift XRT source position (GCN 10930, J.P. Osborne et al.).
A 3 sigma upper limit is set in the I magnitude at 22.0 mag.

This photometry was done by using the DoPHOT and calibrated against the
USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.


GRB_name: GRB100704A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10932
SUBJECT: GRB 100704A: Swift-BAT refined analysis
DATE:    10/07/04 11:58:03 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (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),
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-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 100704A (trigger #426722)
(Grupe, et al., GCN Circ. 10929).  The BAT ground-calculated position is
RA, Dec = 133.639, -24.202 deg, which is 
   RA(J2000)  =  08h 54m 33.3s 
   Dec(J2000) = -24d 12' 08.0" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 85%.
 
The mask-weighted light curve shows an initial very weak peak starting at ~T-70 sec
and peaking at ~T-60 sec.  Then comes the main peak starting at ~T-5 sec,
peaking at ~T+1.5 sec, and ending at ~T+50 sec.  That is followed by a small peak
at ~T+100 sec, and then a larger peak from ~T+140 to ~T+210 sec.
T90 (15-350 keV) is 197.5 +- 23.3 sec (estimated error including systematics).
 
The time-averaged spectrum from T-62.3 to T+202.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.73 +- 0.06.  The fluence in the 15-150 keV band is 6.0 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.76 sec in the 15-150 keV band
is 4.3 +- 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/426722/BA/


GRB_name: GRB100704A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10933
SUBJECT: GRB 100704A: Fermi GBM observation
DATE:    10/07/04 14:45:29 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

S. McBreen (UCD/MPE) reports on behalf of the Fermi GBM Team:

"At 03:35:06.10  UT on 04 July 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100704A (trigger 299907308 / 100704149)
which was also detected by the Swift-BAT (Grupe et al. 2010, GCN 10929).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 63 degrees.

The GBM light curve rises slowly before the trigger and
consists of an initial pulse lasting about ~20 s followed
a softer pulse beginning about T0+150 seconds.
The burst has a duration (T90) of about 214 (+/- 6) s (50-300 keV).

The spectrum from T0-2.3 s to T0+20.2 s is
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.80 (+0.06/-0.06)
and the cutoff energy, parameterized as Epeak, is
193.90 (+14.00/-12.10) keV (CSTAT for 781 for 607 d.o.f.).

The event fluence (10-1000 keV) in this time interval is
(5.8 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.3 s in the 10-1000 keV band
is 7.0 +/- 0.2 ph/s/cm^2.

A Band function fits the spectrum equally well (CSTAT 779 for 606 d.o.f.)
with Epeak= 178.30 (+16.30/-17.50)  keV, alpha = -0.76 (+0.08/-0.07)
and beta = -2.53 (+0.29/-0.54) .

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


GRB_name: GRB100704A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10934
SUBJECT: GRB 100704: Swift/UVOT Upper Limits
DATE:    10/07/04 15:22:17 GMT
FROM:    Patricia Schady at MPE/Swift  <msslba@googlemail.com>

N.P.M. Kuin (MSSL/UCL) and D. Grupe (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100704
96 s after the BAT trigger (Grupe et al., GCN Circ. 10929). No optical
afterglow consistent with the XRT position (Osborne et al., GCN
Circ. 10930) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using a 3" aperture in
the UVOT photometric system (Poole et al. 2008, MNRAS, 383,
627) for the first finding chart (FC) exposure and subsequent
exposures are:

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

white_FC            96          246          147         >21.0
u_FC               308          558          246         >20.2
white               96         6544          746         >21.8
v                  638         6955          471         >20.0
b                  564         6339          452         >21.1
u                  308         6132          678         >21.1
w1                 688         5927          255         >21.1
m2                 662         7075          387         >20.2
w2                 613         6750          471         >20.7

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.17 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100704A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10935
SUBJECT: GRB 100704A: Swift XRT refined analysis 
DATE:    10/07/04 16:18:01 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 6162 s of XRT data for GRB 100704A (Grupe  et al.
GCN Circ. 10929), from 92 s to 18.5 ks  after the  BAT trigger.
The data comprise 317 s in Windowed Timing (WT) mode with the
remainder in Photon Counting (PC) mode. The X-ray light curve displays
a strong flare starting at about 140s and peaking at 190s after the
burst. As mentioned in GCN Circ. 10929, this flare coincides with a
flare seen in the BAT. The rest of the light curve can be  modeled
with a series of power-law decays. After the flare the afterglow
decays with a slope of 0.32 and breaks at about 1 ks after the burst
followed  by a decay slope of 0.76+/-0.06.

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.96 (+/-0.04). The
best-fitting absorption column is  3.23 (+/-0.14) x 10^21 cm^-2, in
excess of the Galactic value of 1.0 x 10^21 cm^-2 (Kalberla et al.
2005). With an excess absorption column density of 2.32 x 10^21 cm^-2
the NH-redshift relation by Grupe et al. (2007, AJ 133, 2216)
suggests a redshift z<3.0.
The PC mode spectrum has a photon index of 2.6 (+/-0.3) and a
best-fitting absorption column of 3.1 (+0.9, -0.8) x 10^21 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.5 x 10^-11 (8.3 x 10^-11) erg cm^-2
count^-1.

If the light curve continues to decay with a power-law decay index of
0.76, the count rate at T+24 hours will be 0.045 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.6 x
10^-12 (3.7 x 10^-12) erg cm^-2 s^-1 and 0.027 counts s^-1 T+48h.

The  UVOT-enhanced position of the afterglow has already been reported
by Osborne et al. (GCN Circ. 10930).

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00426722.

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


GRB_name: GRB100703A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10936
SUBJECT: GRB 100703A: a short GRB detected by INTEGRAL
DATE:    10/07/05 13:29:12 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

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

a short gamma ray burst triggered the IBAS detection programs of the 
IBIS/ISGRI data at 17:43:37.4 UT on July 3rd.
The trigger significance was below the threshold for automatic alert 
distribution. Off-line interactive analysis confirmed that the trigger is 
most likely due to a short GRB, consisting of a single peak with a 
duration of about 70 ms. Its refined coordinates (J2000) are:

RA:    9.522 [deg]
DEC: -25.710 [deg]

with an uncertainty of 2.8  arcmin (90% c.l.).

A preliminary analysis gives a fluence in the 20-200 keV range of about 
7 10e-7 erg/cmsq (70 ms integration time).


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: GRB100704A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10937
SUBJECT: Konus-Wind observation of GRB 100704A
DATE:    10/07/05 13:40:45 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100704A (Swift-BAT trigger=426722;
Grupe et al., GCN 10929; Cummings et al., GCN 10932)
triggered Konus-Wind at T0=12905.409s UT (03:35:05.409)

The burst light curve consists of a single FRED-like pulse
with a total duration of ~30 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100704_T12905/

As observed by Konus-Wind the burst
had a fluence of 6.6(+/-0.7)x10-6 erg/cm2,
and a 256-ms peak flux measured from T0+0.768s
of 1.1(+/-0.2)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+16.640 s) is best fit
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.75(-0.28, +0.33),
and Ep = 176(-24, +35) keV (chi2 = 34/58 dof).

The spectrum at the maximum count rate
(measured from T0+0.256 to T0+8.848 s) is best fit
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.65(-0.27, +0.31),
and Ep = 214(-29, +43) keV (chi2 = 44/58 dof).

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


GRB_name: GRB100701B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10938
SUBJECT: IPN triangulation of GRB 100701B
DATE:    10/07/05 22:08:23 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,

J. Goldsten, and K. Hurley on behalf of the MESSENGER GRNS GRB team,

V. Connaughton, M.S. Briggs, and C.A. Meegan on behalf of the Fermi
GBM team,

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

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, report:

The long bright GRB 100701B, seen by Fermi/GBM (Foley, GCN 10920), has 
also been detected by INTEGRAL (SPI-ACS), Suzaku (WAM),  Konus-Wind, and 
MESSENGER (GRNS) so far.

We have triangulated it to a 3 sigma error box whose coordinates are:
-----------------------------------------------
    RA(2000), deg              Dec(2000), deg
-----------------------------------------------
Center:
   43.109 (02h 52m 26s)    -2.224 (-02d 13' 25")
Corners:
   43.260 (02h 53m 02s)    -2.497 (-02d 29' 49")
   43.081 (02h 52m 19s)    -2.310 (-02d 18' 36")
   42.959 (02h 51m 50s)    -1.947 (-01d 56' 50")
   43.138 (02h 52m 33s)    -2.137 (-02d 08' 14")

-----------------------------------------------

The error box area is 149.7 sq. arcmin.
This error box may be improved.

The GBM position (Foley, GCN 10920) is 2.7 deg from the center of the box.


GRB_name: GRB100701B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10939
SUBJECT: Konus-Wind observation of GRB 100701B
DATE:    10/07/06 08:05:36 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long bright hard GRB 100701B (localized by IPN,
Golenetskii et al., GCN 10938) triggered Konus-Wind
at T0=42319.075s UT (11:45:19.075)

The burst light curve consists of several (>6) short
hard pulses with a total duration of ~15 s.
The emission is clearly seen up to 10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100701_T42319/

As observed by Konus-Wind the burst
had a fluence of 5.0(+/-0.85)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+3.584s
of 2.2+/-0.3)x10-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+16.640 s) is best fit
in the 20 keV - 10 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -0.90 (+/-0.10),
the high energy photon index beta = -2.7 ( <-2.1 ),
the peak energy Ep = 1186(-243, +294)keV (chi2 = 74.4/84 dof).

The spectrum at the maximum count rate
(measured from T0+0.256 to T0+8.848 s) is best fit
in the 20 keV - 10 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -0.80 (+/-0.10),
the high energy photon index beta = -2.6 ( <-2.2 ),
the peak energy Ep = 1202(-217, +246)keV (chi2 = 90/84 dof).

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


GRB_name: GRB100704A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10940
SUBJECT: Tentative redshift of GRB100704A from Swift-XRT data
DATE:    10/07/06 15:45:20 GMT
FROM:    Sergio Campana at INAF-OAB  <sergio.campana@brera.inaf.it>

S. Campana (INAF-OAB) and D. Grupe (PSU) report on behalf of the 
Swift-XRT team:

Swift XRT observed the bright GRB 100704A (Grupe et al. 2010, GCN 10929)
starting 86 s after the BAT trigger. After strong X-ray flares the light 
curve started decaying
following a power law (Grupe 2010, GCN 10935).
We selected the time interval 4,510-28,896 s after the burst onset to 
collect the Photon
Counting (PC) spectrum. During this interval the spectrum is almost 
constant as testified by
a constant power law photon index (chi2=102 with 123 degrees of freedom).

We fit the PC spectrum (comprising 2002 counts) with a (Galactic plus 
intrinsic) absorbed
cutoff power-law model (tbabs*ztbabs*cutoff) within XSPEC (the cutoff 
power-law model
provides much better results in terms of column density evaluation with 
respect to a simple
power-law model when small spectral variations are present).
We assume a Galactic column density of 1.1x1021 cm-2 (Kalberla et al. 
2005, A&A 440 775)
and allowed for a 30% variability given its high value (and sampling all 
the values obtained
within 1 degree from the source).
We fit the spectrum using C-statistics. In the intrinsic column density 
vs. redshift plane there
is a low significance (3 sigma) solution at low redshifts but the 
minimum lies at higher redshifts
with a 2 sigma confidence level solution of z=3.6^+1.1 _-1.2 and N_H 
(z)=(9.7^+9.9 _-5.6 )x10^22 cm^-2 .
Thus, even if we cannot exclude that GRB100704A is at low redshift, a 
high redshift (z~3.5),
highly absorbed (N_H (z)~1x10^23 cm^-2 ) solution is preferred.
This compares well with the non-detection with UVOT (Kuin and Grupe 
2010, GCN 10934)
and MOA robotic telescope (Omori et al. 2010, GCN 10931).
We also note that if no interviening systems are present along the line 
of sight a 90% lower
limit on the metallicity of 0.03 solar can be set (based on the 
assumption that the absorbing
medium is not Thomson thick).

The contour plot is available at
http://www.brera.inaf.it/utenti/campana/100704.gif


GRB_name: GRB100628A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10941
SUBJECT: GRB 100628A: Swift XRT/UVOT refined analysis
DATE:    10/07/06 21:54:09 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C. Starling, P.A. Evans (U. Leicester) and S. Immler (CRESST/GSFC/UMD) 
report on behalf of the Swift XRT and UVOT teams,

We have analysed 65.4 ks of Swift XRT data for GRB 100628A (Immler et al. GCN 
Circ. 10895). The X-ray source reported in Starling et al. (GCN Circ. 10907) 
shows no evidence for fading. We conclude that this source is not the 
X-ray afterglow of GRB 100628A.

Further inspection of these data reveal another possible X-ray source close
to the persistant source, detected in the first two orbits of data only 
(totalling 3.8 ks from T0+92 s to T0+7200 s). 
This source comprises just 7 counts, however the predicted background 
level is only 0.7 counts in this time interval. Using the Bayesian method 
described in Kraft, Burrows & Nousek (1991) we find a detection 
significance >99.999%. The 0.3-10 keV count rate during this interval is 
0.0017 (+0.0008, -0.0006) counts/s. The source position is
RA, Dec (J2000) = 225.96837, -31.65839, which is equivalent to:
   RA (J2000)  = 15 03 52.41
   Dec (J2000) = -31 39 30.2
with an uncertainty of 7 arcseconds (radius, 90% containment).

In the subsequent XRT data (>T0+7200 s) the source is not detected; a 
3-sigma upper limit on the 0.3-10 keV count rate is 5.7E-5 count/s. 
Therefore, if this source was real it has faded and can be considered a 
candidate X-ray afterglow.
We caution that with so few total counts a background fluctuation or other
spurious detection cannot be completely ruled out.

No UVOT afterglow candidate is seen in any of the UVOT images at the XRT
position down to the limits reported in GCN 10901.

This circular is an official product of the Swift team.


GRB_name: GRB100628A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10942
SUBJECT: GRB 100628A:  Chandra observations
DATE:    10/07/06 22:27:15 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) reports:

"We observed the field of the short GRB 100628 (GCN 10895) with the
Chandra X-ray Observatory starting on 2010 July 2.79 UT for a total of
19.8 ksec.  Within the XRT error circle (GCN 10907) we detect a single
point source at the following coordinates (J2000):

       RA = 15:03:53.33
       DEC = -31:39:50.5

This object is coincident with the bright core of the galaxy "G1"
(GCNs 10902,10908).  The flux of the object is about 4.8e-14
erg/cm^2/s, in good agreement with the flux measured with the
Swift/XRT of about 4.6e-14 erg/cm^2/s (see Swift/XRT GRB lightcurve
repository: http://www.swift.ac.uk/xrt_curves/00426114/).  Given the
position of the source and its constant flux we conclude that it is
due to AGN activity and is therefore not related to GRB 100628 (see
also GCN 10941).

Furthermore, we do not detect any emission at the location of the new
and possibly fading XRT source (GCN 10941) to a 3-sigma limit of
<5e-15 erg/cm^2/s, about a factor of 15 times fainter than the initial
XRT detection.

We thank Harvey Tananbaum and the CXO scheduling staff for rapidly
approving and executing this observation."


GRB_name: GRB100628A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10943
SUBJECT: GRB 100628A:  Near-IR sources coincident with the possible X-ray afterglow
DATE:    10/07/06 22:58:34 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) reports:

"We inspected the location of the new and possibly fading XRT source
(GCN 10941) associated with the short GRB 100628 (GCN 10895) in our
Magellan/PANIC images (GCNs 10902,10908,10911).  Within the 7" radius
circle we detect two extended sources at the following positions (J2000):

G6: RA = 15:03:52.02, DEC = -31:39:32.5
G7: RA = 15:03:52.78, DEC = -31:39:33.7

Neither source shows any evidence for fading between our two PANIC
observations from 0.65 and 21.8 hours after the burst."


GRB_name: GRB100707A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10944
SUBJECT: GRB 100707A: Fermi GBM detection
DATE:    10/07/07 18:44:31 GMT
FROM:    Colleen A. Wilson at NASA/MSFC/NSSTC  <colleen.wilson@nasa.gov>

Colleen A. Wilson-Hodge (NASA/MSFC) and Suzanne Foley (MPE) 
report on behalf of the Fermi GBM Team: 

"At 00:46:38.99 UT on 07 July 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100707 (trigger 300156400 / 100707.032).

The on-ground calculated location, using the GBM trigger 
data, is RA = 351.07, DEC = -6.57 (J2000 degrees, 
equivalent to 23 h 24 m, -6 d 34 '), with an uncertainty 
of 1 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 90 degrees.

The GBM light curve show a fast rise and exponential decay
with a duration (T90) of 82+/-1 s (50-300 keV). 
The time-averaged spectrum from T0-0.064 s to T0+83.009 s is 
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.91 +/- 0.02 and
the cutoff energy, parameterized as Epeak, is 283 +/- 7 keV

(C-Statistic 529.4 for 358 d.o.f.).

The event fluence (10-1000 keV) in this time interval is 
(8.77 +/- 0.02)E-05 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+1.152 s in the 10-1000 keV band 
is 48.3 +/- 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: GRB100707A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10945
SUBJECT: GRB 100707A: Fermi LAT detection 
DATE:    10/07/07 22:03:09 GMT
FROM:    James Chiang at SLAC  <jchiang@slac.stanford.edu>

Veronique Pelassa (LPTA), Melissa Pesce-Rollins (INFN-Pisa) report on
behalf of the Fermi LAT collaboration:

The Fermi Large Area Telescope (LAT) detected emission from GRB
100707A (C. Wilson-Hodge et al, GCN 10944).

This burst was at an angle of 90 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, the LAT light curve shows a
single, sharply rising pulse that has a somewhat more gradual decay,
similar to the initial peak in the GBM light curve. The LAT T90
duration is <30 s. This is shorter than the GBM T90 (82+/-1 s), but
the LAT may be missing a long tail at later times owing to noisier
data. Over 300 counts above background were detected within a 5 s
interval in coincidence with the main GBM peak. The significance of
this excess was greater than 14 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 Veronique Pelassa
(pelassa@lpta.in2p3.fr).

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: GRB100628A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10946
SUBJECT: GRB 100628A: Keck/LRIS Spectroscopy of Host Galaxy Candidate
DATE:    10/07/08 13:54:02 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko, D. A. Perley, J. S. Bloom, A. N. Morgan (UC Berkeley), and A.
Cucchiara (UCB/LBNL/UCSC) report on behalf of a larger collaboration:

We have obtained spectra of the galaxy dubbed "G7" (Berger, GCN 10943)
inside the possible X-ray afterglow error circle (Starling et al., GCN
10941) of the short GRB 100628A (Immler et al., GCN 10895) with the Low
Resolution Imaging Spectrometer mounted on the 10 m Keck I telescope.  Our
observations began at 6:25 UT on 8 July 2010 and cover the wavelength
range from 3500-10000 A.

The spectrum is comprised of a series of narrow emission lines, clearly
resolved into two spatially distinct components and joined by a bridge of
faint continuum emission, possibly indicating an interacting or disturbed
system.  We identify the emission lines in both components as [O II], [O
III], H-alpha, and H-beta at a common redshift of z = 0.102, which we
therefore take to be the redshift of the galaxy "G7".


GRB_name: GRB100707A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10947
SUBJECT: IPN triangulation of GRB 100707A
DATE:    10/07/08 21:49:15 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

K. Hurley and J. Goldsten, on behalf of the MESSENGER GRNS 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,

V. Connaughton, M.S. Briggs, and C.A. Meegan on behalf of the Fermi
GBM team, and

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, report:

The long bright GRB 100707A, observed by Fermi/GBM at 00:46:38.99 UT 
(Wilson-Hodge & Foley, GCN 10944) and Fermi/LAT (Pelassa & 
Pesce-Rollins, GCN 10945), has also  been detected by Suzaku (WAM), 
Konus-Wind, and MESSENGER (GRNS) so far.

We have triangulated it to a preliminary 3 sigma error box whose 
coordinates are:
-----------------------------------------------
    RA(2000), deg              Dec(2000), deg
-----------------------------------------------
Center:
  358.019 (23h 52m 05s)    -8.658 (-08d 39' 29")
Corners:
  358.562 (23h 54m 15s)   -11.226 (-11d 13' 32")
  358.773 (23h 55m 05s)   -11.654 (-11d 39' 14")
  357.369 (23h 49m 29s)    -5.832 (-05d 49' 56")
  357.116 (23h 48m 28s)    -5.295 (-05d 17' 42")
-----------------------------------------------

The error box area is 0.660 sq. deg
This error box may be improved.

The GBM position (Wilson-Hodge & Foley, GCN 10944) is 7.2 deg from the 
center of the box.


GRB_name: GRB100707A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10948
SUBJECT: Konus-Wind observation of GRB 100707A
DATE:    10/07/09 10:09:17 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The very bright long GRB 100707A
(Fermi/GBM trigger 300156400: Wilson-Hodge and Foley, GCN 10944;
localized by IPN: Hurley et al., GCN 10947)
triggered Konus-Wind at T0=2798.855s UT (00:46:38.855)

The burst light curve consists of a single FRED pulse
with a duration of ~100 s.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100707_T02798/
The periodic dips seen in the 64-ms lc are caused
by the occultation of the Konus detector
by other instrument on board the rotating Wind s/c.

As observed by Konus-Wind the burst
had a fluence of 8.8(+/-0.6)x10-5 erg/cm2,
and a 64-ms peak flux measured from T0+1.344s
of 2.4(+/- 0.2)x10-5 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+102.144 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -0.95 (+/-0.15),
the high energy photon index beta = -2.2 (-0.3, +0.2),
the peak energy Ep = 264(-40, +49)keV (chi2 = 43.5/57 dof).

The spectrum at the maximum count rate
(measured from T0+1.280 to T0+1.792 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = +0.3 (-0.3, +0.5),
the high energy photon index beta = -2.4 (-0.5, +0.3),
the peak energy Ep = 383(-82, +80)keV (chi2 = 53.2/57 dof).

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


GRB_name: GRB100707A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10950
SUBJECT: GRB 100707A: Suzaku WAM observation of the prompt emission
DATE:    10/07/10 07:02:25 GMT
FROM:    Yoshitaka Hanabata at Hiroshima U  <hanabata@hep01.hepl.hiroshima-u.ac.jp>

Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.)
K. Yamaoka (Aoyama Gakuin U.), S. Sugita (Nagoya U.),
Y. Terada, M. Tashiro, W. Iwakiri, K. Takahara, T. Yasuda (Saitama U.),
M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. E. Nakagawa, T. Tamagawa (RIKEN), N. Ohmori, A. Daikyuji, Y. Nishioka,
M. Yamauchi (Univ. of Miyazaki), N. Vasquez (Tokyo Tech.), Y. Urata,
H. M. Lin (NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo),
S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:

The long GRB 100707A (Fermi/GBM trigger #300156400; C. Wilson-Hodge et al.,
GCN 10944; Fermi-LAT detection; V. Pelassa et al., GCN 10945)
triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an
energy of 50 keV - 5 MeV at 2010-07-07 00:46:38.91 UT (T=0).

The observed light curve shows a FRED-like peak structure lasting from
T0-0.5s to T0+18.5s with T90 of about 12 seconds. The fluence in 100 -
1000 keV was 5.26 (+/-0.27) x 10^-5 erg/cm^2. The 1-s peak flux
measured from T0+1.5s was 32.24 (-1.28, +1.22) photons/cm^2/s in the
same energy range.

Preliminary result shows that the time-averaged spectrum from T0-0.5s
to T0+18.5s is well fitted by a single power-law with a photon index
of 2.15 (-0.05, +0.06) (chi^2/d.o.f = 39.4/25).

Due to the brightness of this burst, a 3% systematic error was added
for low energy channels.  In addition, there might be some calibration
uncertainties in these spectral parameters because GRB photons came to
the WAM detector by passing through the large Ne dewar of the X-ray
micro-calorimeter (XRS).
All the errors are quoted at 90% confidence level.

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


GRB_name: GRB100713A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10951
SUBJECT: GRB 100713A: a long GRB detected by INTEGRAL
DATE:    10/07/13 15:41:58 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

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

a gamma ray burst lasting about 20 s has been detected by IBAS in the 
IBIS/ISGRI data at 14:36:06 U.T. on July 13th.

Its refined coordinates (J2000) are:

RA: 255.209 [degrees]
DEC: 28.390 [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 
0.4 ph/cmsq/s (1 s integration time) and a fluence over the same energy 
range of about 2 10e-7 erg/cmsq.


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: GRB100713A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10952
SUBJECT: GRB100713A: Swift X-ray afterglow detection
DATE:    10/07/13 16:46:58 GMT
FROM:    Neil Gehrels at GSFC  <gehrels@milkyway.gsfc.nasa.gov>

V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU),
E. A. Hoversten (PSU), K. L. Page (U Leicester) and M. H. Siegel (PSU)
report on behalf of the Swift Team:

Swift began a target of opportunity observation of GRB100713A on July
13, 2010 at 16:30 UT, approximately 1.9 hours after the burst was
detected by INTEGRAL. Swift data for these observations utilize Target
ID 20143. 

The XRT began observing the field at 16:20:34.3 UT, 6.2 ks after the
INTEGRAL trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 255.20192, 28.39489 which
is equivalent to:
   RA(J2000)  = 17h 00m 48.46s
   Dec(J2000) = +28d 23' 41.6"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
location is 29 arcseconds from the INTEGRAL position, within the
INTEGRAL error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper.  We cannot determine whether the source is
fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (5.01e+20
cm^-2, Kalberla et al. 2005), with an excess column of 7.2
(+8.61/-6.14) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 6246 seconds after the INTEGRAL 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 19.6 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 0.06. 

Burst Advocate for this burst is V. D'Elia (delia 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: GRB100713A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10953
SUBJECT: GRB 100713A: TELMA and 1.5m OSN optical observations
DATE:    10/07/13 22:21:28 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

F. J. Aceituno, J. C. Tello, M. Jelnek, P. Kubnek, J. Gorosabel, S.
Guziy, A. J. Castro-Tirado (IAA-CSIC Granada) and A. de Ugarte Postigo
(INAF-OAB Brera), report:

"Following the detection of GRB 100713A by INTEGRAL (Mereghetti et al.
GCNC 10951), we have obtained optical images with the 0.6m TELMA robotic
telescope at the BOOTES-2 station and with 1.5m telescope at the
Observatorio de Sierra Nevada (OSN), both located in Southern Spain.

At the position of the X-ray afterglow detected by SWIFT/XRT (D'Elia et
al. GCNC 10952) we do not detect any optical source down to I = 23 in
the co-added 1.5m OSN image (3600-s exposure at 21:07 UT, i.e. 6.5-hr
after the onset of the burst).

Due to the low Galactic extinction (Av = 0.2), this INTEGRAL GRB is very
suitable for follow up. Deeper observations (specially at near-IR
wavelengths) are encouraged".

This message can be quoted.


GRB_name: GRB100713A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10954
SUBJECT: GRB 100713A: TNG optical observations
DATE:    10/07/13 23:14:45 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo (INAF-OAB), L. A. Antonelli (INAF-OAR), V. D'Elia (ASDC), D.
Fugazza (INAF-OAB), A. de Ugarte Postigo (INAF-OAB), D. Malesani
(DARK/NBI) on behalf of the CIBO collaboration report:

We observed the field of GRB100713A (Mereghetti et al. GCN 10951) with the
Italian 3.6m TNG telescope (La Palma, Canary Islands) equipped with the
DOLORES camera operated in imaging mode. Observations started on Jul 13 at
21:25 UT (~6.8 after the GRB) and were carried out in R and I band for a
total exposure time of 900s and 540s, respectively. We do not detect any
source within the XRT error circle (D'Elia et al., GCN 10952) in both
filters down to a limiting magnitude of I~22.6 and R~23.6 (3sigma c.l.,
calibrated against the USNO B1 catalogue). We note the presence of a faint
source visible in both our images and the SDSS close to the the border of
the XRT error circle at the following coordinates (J2000):

R.A.=17:00:48.1
Dec=+28:23:45.7

We thank Gian Paolo Tozzi and Giovanni Mainella for performing the
observations and for their support.


