# GCN_circulars

GRB_name: GRB141221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17208
SUBJECT: GRB141221A: REM afterglow
DATE:    14/12/21 15:01:52 GMT
FROM:    Stefano Covino at Brera Astronomical Observatory  <stefano.covino@brera.inaf.it>

S. Covino (INAF/OAB) on behalf of the REM team:

We observed the field of the GRB141221A (Sonbas et al., GCN 17206) simultaneously in the optical and near infrared with the 60-cm robotic telescope REM at La Silla Observatory (Chile). The observations started about 1 min after the GRB, when the field was at an airmass of about 2.5 and continued for about one hour till the local twilight.

A bright source at a position consistent with the UVOT candidate afterglow is detected in all filter (grizJHK). 
At about 1.5 min after the GRB the afterglow was H~13.1 and faded down to H~15.8 more than 30 min later, with a decay index alpha~0.8. 


GRB_name: GRB141221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17209
SUBJECT: GRB 141221A: LCOGT-McDonald optical afterglow observations
DATE:    14/12/21 15:07:45 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

C. Guidorzi, S. Dichiara (U. Ferrara), D. Kopac, A. Gomboc (U. Ljubljana)
on behalf of a larger collaboration report:

The 1-m LCOGT McDonald telescope began observing Swift GRB 141221A
(Sonbas et al. GCN 17206) on Dec 21 at 10:26:35 UT, corresponding
to 2.3 hours after the burst trigger, with SDSS r' and i' filters.
We detect the optical afterglow (Sonbas et al. GCN 17206; Covino
GCN 17208) with i'=20.1 +- 0.3 mag at a mid time of 2.61 hours
post burst (total exposure of 600 s).


GRB_name: GRB141221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17210
SUBJECT: GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
DATE:    14/12/21 15:16:10 GMT
FROM:    Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet  <atrotter@physics.unc.edu>

A. Trotter, J. Haislip, D. Reichart, A. Aji, R. Beauchemin, T. Berger, 
A. Dow, A. Foster, N. Frank, M. Hinckle, K. Ivarsen, A. LaCluyze, M. 
Maples, J. Moore, M. Nysewander, C. Salemi, L. Zbinden, and J. A. Crain 
report:

Skynet observed the Swift BAT/XRT localization of GRB 141221A (Sonbas et 
al., GCN 17206, Swift trigger=622006) with two 14" telescopes of the 
PROMPT array at Cerro Tololo, Chile. Starting at 2014-12-21 08:07:56 UT 
and continuing until 08:35 UT (t=45s-28m post-trigger), Skynet took a 
total of 44 exposures ranging from 5s to 160s in the V and I bands. We 
clearly detect the optical afterglow (Covino, GCN 17208, Guidorzi et 
al., GCN 17209) with a rising light curve prior to t=2min, where it 
peaks at I=14.8.

A preliminary light curve is at:

http://www.skynet.unc.edu/grb/grb141221a.png

Magnitudes are in the Vega System, calibrated to 3 APASS stars in the 
field.  Magnitudes have not been corrected for line-of-sight Milky Way 
dust extinction, with expected E(B-V)=0.024 (Schlafly & Finkbeiner 2011).

Skynet observations will continue.


GRB_name: GRB141221A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17211
SUBJECT: GRB 141221A: Enhanced Swift-XRT position
DATE:    14/12/21 17:56:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 4183 s of XRT Photon Counting mode data and 6 UVOT
images for GRB 141221A, 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 = 198.28686, +8.20510 which is equivalent
to:

RA (J2000): 13h 13m 8.85s
Dec (J2000): +08d 12' 18.4"

with an uncertainty of 1.6 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: GRB141221A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17212
SUBJECT: GRB141221A: GROND Afterglow Detection
DATE:    14/12/21 19:03:57 GMT
FROM:    Philip Wiseman at MPE/Swift  <wiseman@mpe.mpg.de>

GRB 141221A: GROND Detection of the Optical/NIR Afterglow

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

We observed the field of GRB 141221A (Swift trigger 622006; Sonbas et al.,
GCN #17206) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started at 08:09:33 UT on 21/12/2014, 142 seconds after the
GRB trigger, and continued in all bands for ~18 minutes of exposures until
the beginning of twilight, and in NIR for another 4 minute exposure. They
were performed at an average seeing of 1.7" and at an average airmass of
2.1.

We find a single point source, consistent with the enhanced SWIFT-XRT
position of Beardmore et al. (GCN #17211) and that reported by e.g. Covino
(GCN 17208), Trotter et al. (GCN #17210),  at:

RA (J2000) = 13h 13m 08.80s

DEC (J2000) = +08d 12' 18.9"

with an uncertainty of 0.2" in both co-ordinates.

There were problems with telescope pointing throughout the observations,
Based on our first short exposures in grizJHK, we estimate preliminary
magnitudes (all in AB system) of

g' = 17.1 +/- 0.1 mag,
r' = 16.6 +/- 0.1 mag,
i' = 16.4 +/- 0.1 mag,
z' = 16.1 +/- 0.1 mag,
J = 15.7 +/- 0.1 mag,
H = 15.4 +/- 0.1 mag, and
K = 15.3 +/- 0.1 mag.

The best-fit SED has a spectral index beta = 1.0 +/- 0.1.

Given magnitudes are not corrected for the expected Galactic foreground
extinction corresponding to a reddening of E_(B-V)=0.024 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB141221A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17213
SUBJECT: GRB 141221A: Swift-BAT refined analysis
DATE:    14/12/21 19:28:45 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), E. Sonbas (NASA/GSFC/Adiyaman Univ.), M. Stamatikos (OSU),
J. Tueller (GSFC)
(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 141221A (trigger #622006)
(Sonbas, et al., GCN Circ. 17206).  The BAT ground-calculated position is
RA, Dec = 198.283, 8.197 deg, which is 
   RA(J2000)  =  13h 13m 07.9s 
   Dec(J2000) = +08d 11' 49.8" 
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 78%.
 
The mask-weighted light curve shows some low-level precursor emission
starting at ~T-23 sec with the first peak starting at ~T-3 sec, peaking
at ~T+1 sec, and the second peak peaking at ~T+14 sec, and ending at T+35 sec.
T90 (15-350 keV) is 36.9 +- 4.0 sec (estimated error including systematics).
 
The time-averaged spectrum from T-24.11 to T+20.33 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.74 +- 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-0.10 sec in the 15-150 keV band
is 3.1 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/622006/BA/


GRB_name: GRB141221A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17214
SUBJECT: GRB 141221A: Swift-XRT refined Analysis
DATE:    14/12/21 20:21:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. Maselli  (INAF-IASFPA), A. Melandri (INAF-OAB), B. Sbarufatti
(INAF-OAB/PSU), D.N. Burrows (PSU), J.A. Kennea (PSU), V. Mangano
(PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Pagani
(U. Leicester) and E. Sonbas report on behalf of the Swift-XRT team:

We have analysed 8.9 ks of XRT data for GRB 141221A (Sonbas  et al. GCN
Circ. 17206),  from 64 s to 34.9 ks after the  BAT trigger. The data
comprise 48 s in Windowed Timing (WT) mode (the first 8 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 Beardmore
et al. (GCN Circ. 17211).

The late-time light curve (from T0+3.9 ks) can be modelled with  a
power-law decay with a decay index of alpha=1.26 (+0.17, -0.16).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.26 (+0.21, -0.20). The
best-fitting absorption column is  3.1 (+0.8, -0.7) x 10^21 cm^-2, in
excess of the Galactic value of 2.3 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.3 x 10^-11 (5.6 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      3.1 (+0.8, -0.7) x 10^21 cm^-2
Galactic foreground: 2.3 x 10^20 cm^-2
Excess significance: 6.7 sigma
Photon index:      2.26 (+0.21, -0.20)

If the light curve continues to decay with a power-law decay index of
1.26, the count rate at T+24 hours will be 3.5 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x
10^-13 (2.0 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/00622006.

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


GRB_name: GRB141220A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17215
SUBJECT: GRB 141220A: MITSuME Akeno upper limits
DATE:    14/12/22 07:06:48 GMT
FROM:    Taketoshi Yoshii at Tokyo Tech  <yoshii.t.ac@m.titech.ac.jp>

Y. Yano, T. Yoshii, Y. Saito, Y. Tachibana, H. Ohuchi,
S. Kurita, Y. Ono, T. Fujiwara, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:

We observed the field of GRB 141220A (J. R. Cummings et al., GCN Circular #17196) with the
optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.

The observation started on 2014-12-20 15:16:22 UT (~9.2 h after the burst).
We did not find any new point source within the refined XRT error circle 
(B. P. Gompertz., GCN Circular #17203) in all the three bands.

The measured magnitudes are listed below.

T0+[sec]     MID-UT    T-EXP[sec]        g'         Rc        Ic
-----------------------------------------------------------------------------
36707        18:07:29        8460          >21.4  >20.8  >20.4
-----------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.


GRB_name: GRB141221A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17216
SUBJECT: GRB 141221A: Fermi GBM observation
DATE:    14/12/22 08:29:06 GMT
FROM:    Hoi-Fung Yu at MPE  <sptfung@mpe.mpg.de>

H.-F. Yu (MPE) reports on behalf of the Fermi GBM Team:

"At 08:07:11.22 UT on 21 Dec 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 141221A (trigger 440842034 / 141221338),
which was also detected by Swift (Sonbas et al. 2014, GCN 17206).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is about 76 degrees.

The GBM light curve consists of two pulses with a duration (T90) of
about 23.8 s (50-300 keV). The time-averaged spectrum from T0-1.024 s
to T0+17.408 s is best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.07 +/- 0.13 and the
cutoff energy, parameterized as Epeak, is 152.4 +/- 28.5 keV.

The event fluence (8-1000 keV) in this time interval is
(3.4 +/- 0.4)E-06 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0-0.192 s in the 8-1000 keV band
is 5.4 +/- 0.3 ph/s/cm^2.

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


GRB_name: GRB141215A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17217
SUBJECT: GRB 141215A: further Swift-XRT observations and afterglow detection
DATE:    14/12/22 16:56:41 GMT
FROM:    Valerio D'Elia at ASDC  <delia@asdc.asi.it>

V. D'Elia (ASDC), L. Izzo (URoma/ICRA) & M. M. Chester (PSU) report on  
behalf of the Swift team

Swift-XRT observed again the field of the IPN GRB 141215A (Hurley et  
 al. GCN 17186). The  observation started on 2014-12-21 at 01:22UT,  
i.e., ~5.5 days after the burst detection. Source #1 (that with a  
2MASS counterpart) and source #3 (which has a DSS counterpart)  
reported by D'Elia & Izzo (GCN 17190) are still detected with a count  
rate comparable to that of the first exposure and are thus not related  
with the GRB. On the other hand, source #2 faded  considerably with  
respect to the first observation. Its decay index is alpha~1, which is  
consistent with a typical afterglow behavior. We thus conclude that  
source #2 is the X-ray counterpart of GRB 141215A.

Swift/UVOT observed the initial two tiled fields for GRB 141215A  
beginning ~100 ks after the IPN trigger. No optical counterpart was  
detected for Swift/XRT Source #2 (D'Elia et al. GCN Circ. 17190).  
Preliminary 3-sigma upper limits using the UVOT photometric system  
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) are:

Source #2:
Filter         T_start(s)   T_stop(s)      Exp(s)      UL
white          118715       125192         1026      > 21.35
v              119529       120370          824      > 19.39
u              117902       124472         1580      > 20.85

The magnitudes in the table are not corrected for the Galactic  
extinction due to the reddening of E(B-V) = 0.176 in the direction of  
the burst (Schlegel et al. 1998).

Details on the XRT analysis can be found at:

http://www.swift.ac.uk/xrt_products/TILED_GRB00035/

This is an official product of the Swift team.


GRB_name: GRB141222A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17218
SUBJECT: GRB 141222A: Fermi-LAT detection
DATE:    14/12/22 17:22:49 GMT
FROM:    Julie McEnery at NASA/GSFC  <julie.e.mcenery@nasa.gov>

J. McEnery (GSFC), D. Kocevski (GSFC), J. Racusin (GSFC), F. Longo 
(University of Trieste and INFN), E.Bissaldi (University of Trieste and 
INFN), and M. Axelsson (KTH Royal Institute of Technology) report on 
behalf of the Fermi-LAT team:

At  07:09:04 UT Mon on Month 22, 2014, Fermi-LAT detected high-energy 
emission from GRB 141222A,
which was also detected by Fermi-GBM (trigger 440924940/141222298).

The best LAT on-ground location is found to be RA, Dec 178.04, -57.35 
(J2000) with an error radius of 0.1 deg (90% containment, statistical 
error only) based on a 500s integration. This was 46 deg from the LAT 
boresight at the time of the trigger.

The data from the Fermi-LAT show a significant increase in the event 
rate within 15 degree of the GBM location after the GBM trigger that is 
spatially and temporally correlated with the GBM emission with high 
significance. More than 5 photons above 100 MeV and more than 1 photon 
above 1 GeV are observed within 1 seconds. The highest-energy prompt 
photon is a 20 GeV event which is observed 0.1 seconds after the GBM 
trigger.

The Fermi-LAT point of contact for this burst is Magnus Axelsson 
(magnusa@astro.su.se <mailto:magnusa@astro.su.se>).

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.


GRB_name: GRB141221A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17219
SUBJECT: GRB 141221A: Swift/UVOT Detection
DATE:    14/12/22 17:26:04 GMT
FROM:    Frank Marshall at GSFC  <femarsha@khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and E. Sonbas (NASA/GSFC/Adiyaman Univ.)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 141221A
84 s after the BAT trigger (Sonbas et al., GCN Circ. 17206).
A source consistent with the enhanced XRT position
(Beardmore et al. GCN Circ. 17211)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  13:13:08.81 = 198.28672 (deg.)
    Dec (J2000) = +08:12:18.8  =   8.20522 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: 

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

white               84          234          147         17.33  0.04
v                  626          646           19         17.43  0.26
b                  552          571           20         17.92  0.21
u                  296          546          246         17.62  0.07
w1                4061         4261          197        >20.0
m2                3856        10742          414        >20.9
w2                6231         6399          165        >20.5

The magnitudes in the table 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: GRB141222A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17220
SUBJECT: GRB 141222A: Fermi GBM detection
DATE:    14/12/22 18:56:06 GMT
FROM:    Peter Jenke at MSFC  <peter.a.jenke@nasa.gov>

P. Jenke (UAH) reports on behalf of the Fermi GBM Team:

"At 07:08:57.40 UT on December 22 2014, the Fermi Gamma-Ray Burst 
Monitor triggered and located 
GRB 141222A (trigger 440924940/141222298), which was also detected
by  Fermi/LAT (J. McEnery et al. 2014, GCN 17218).
The GBM on-ground location, using the Fermi GBM trigger data, is consistent with
the Fermi/LAT location.

The angle of the burst direction to the Fermi LAT boresight is 
46 degrees.

The GBM light curve consists of a narrow peak followed by a broad peak with a tail.
The duration (T90) is about 2.4 s (50-300 keV).
The time-averaged spectrum from T0-0.06 s to T0+1.41 s is
adequately fit by a Band function with Epeak = 2427 +/- 580 keV,
Alpha =-1.49 +/- 0.01 and Beta = -1.74 +/- 0.05.

The event fluence (10-1000 keV) in this time interval is
(8.16 +/- 0.08)E-06 erg/cm^2. The 64 ms peak photon flux measured
starting from T0+0.64 s in the 10-1000 keV band
is 121 +/- 3 ph/s/cm^2.

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


GRB_name: GRB141221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17221
SUBJECT: GRB 141221A: Continued Skynet PROMPT-CTIO observations
DATE:    14/12/22 20:18:17 GMT
FROM:    Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet  <atrotter@physics.unc.edu>

A. Trotter, J. Haislip, D. Reichart, A. Aji, R. Beauchemin, T. Berger, 
A. Dow, A. Foster, N. Frank, M. Hinckle, K. Ivarsen, A. LaCluyze, M. 
Maples, J. Moore, M. Nysewander, C. Salemi, L. Zbinden, and J. A. Crain 
report:

Skynet continued to observe the Swift UVOT localization of GRB 141221A 
(Sonbas et al., GCN 17206, Swift trigger=622006) with two 16" telescopes 
of the PROMPT array at Cerro Tololo, Chile. Starting at 2014-12-22 07:08 
UT and continuing until 08:34 UT (t=23.0h-24.5h post-trigger), Skynet 
took a total of 64 exposures of 160s each in the V and I bands. We 
stacked subsets of these images to maximize the signal-to-noise ratio. 
We no longer detect the optical afterglow that we described in Trotter 
et al. (GCN 17210).

Our limiting magnitudes are:

==================================
tmid  expos  fil  limit
==================================
23.8h 32x160s V   >21.2
23.8h 31x160s I   >20.7

A preliminary light curve is at:

http://www.skynet.unc.edu/grb/grb141221a_2.png

Magnitudes are in the Vega System, calibrated to 3 APASS stars in the 
field.  Magnitudes have not been corrected for line-of-sight Milky Way 
dust extinction, with expected E(B-V)=0.024 (Schlafly & Finkbeiner 2011).

No further Skynet observations are scheduled.


GRB_name: GRB141221A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17222
SUBJECT: GRB 141221A: MITSuME Akeno upper limits
DATE:    14/12/23 11:00:16 GMT
FROM:    Taketoshi Yoshii at Tokyo Tech  <yoshii.t.ac@m.titech.ac.jp>

Y. Ono, T. Yoshii, Y. Saito, Y. Tachibana, H. Ohuchi,
Y. Yano, S. Kurita, T. Fujiwara, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:

We observed the field of GRB 141221A (E .Sonbas et al., GCN Circular #17206) with the
optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.

The observation started on 2014-12-21 17:20:13 UT (~9.1 h after the burst).
We did not find any new point source within the refined XRT error circle
(A.P. Beardmore., GCN Circular #17211) in all the three bands.

The measured magnitudes are listed below.

T0+[sec]     MID-UT    T-EXP[sec]        g'         Rc        Ic
-----------------------------------------------------------------------------
33183        18:51:55        9600          >21.3   >20.8   >20.2
-----------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.


GRB_name: GRB141222A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17223
SUBJECT: IPN Triangulation of GRB 141222A (very intense)
DATE:    14/12/23 14:53:35 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,

V. Connaughton, M. S. Briggs, C. Meegan, and V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team, and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
report:

The hard-spectrum, very intense GRB 141222A has been observed by
Fermi (GBM: Jenke, GCN Circ. 17220; LAT: McEnery et al., GCN Circ. 
17218), Konus-Wind, INTEGRAL (SPI-ACS), and MESSENGER (GRNS), so far, at 
about 25737 s UT (07:08:57).

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   178.156 (11h 52m 38s) -57.280 (-57d 16' 47")
  Corners:
   178.029 (11h 52m 07s) -57.604 (-57d 36' 15")
   178.063 (11h 52m 15s) -57.239 (-57d 14' 20")
   178.284 (11h 53m 08s) -56.954 (-56d 57' 15")
   178.250 (11h 53m 00s) -57.321 (-57d 19' 15")
  ---------------------------------------------
The error box area is 138 sq. arcmin, and its maximum
dimension is 40 arcmin (the minimum one is 6 arcmin).

This box may be improved.

The box overlaps with about a half of the Fermi-LAT error circle, 
reported in GCN Circular 17218, with the center of the circle lying 
slightly outside the box.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB141222_T25735/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming 
GCN Circular.


GRB_name: GRB141222A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17224
SUBJECT: GRB 141222A: First MASTER-SAAO optical observation
DATE:    14/12/23 16:08:15 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

D.Buckley, S. Potter, A. Kniazev
South African Astronomical Observatory

E. Gorbovskoy,V. Lipunov,  P.Balanutsa, D.Denisenko, 
M.Pruzhinskaya,A.Kuznetsov, V.Kornilov, D.Kuvshinov, N.Tyurina
Lomonosov Moscow State University,
Sternberg Astronomical Institute

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National 
University, Argentina


MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
instaleted several days ago  in South African Astronomical 
Observatory (Sutherland) automaticaly was pointed 
to the  Fermi_LAT GRB141222A (McEnery et al., GCN 17218)  after error box 
rised     at 2014-12-22 22:34:35 UT (15.5 hours  after trigger time) in 
unfiltered regime.

Because we have no reference images we can only use DSS stars.
There is no any optical transients brighter  20.8 unfiltered magnitude
inside error box (between 2014-12-22 22:34:35 and 2014-12-23 00:26:09).

We note that error box has small Galactic Latitude b = 4.3 but no very
big absorption in R and I, they  are 0.9 and 0.7 correspondently (Schlafly 
& Finkbeiner 2011, ApJ 737, 103).

This message may be cited.


GRB_name: GRB141222A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17225
SUBJECT: Konus-Wind observation of GRB 141222A
DATE:    14/12/23 16:53:34 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

The long-duration, hard-spectrum, very intense GRB 141222A
(Fermi-LAT detection: McEnery et al., GCN Circ. 17218;
IPN triangulation: Golenetskii et al., GCN Circ. 17223)
triggered Konus-Wind at T0=25735.342 s UT (07:08:55.342).

The burst light curve starts with a short bright pulse with negligible 
spectral lag followed by two broader, less intense, pulses. The total 
burst duration is about 3.2 s. The emission is seen up to 5 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB141222_T25735/
The background variations in the soft KW band are due to solar activity.

As observed by Konus-Wind, the burst
had a fluence of 1.1(-0.2,+0.4)x10^-5 erg/cm2,
and a 16-ms peak flux, measured from T0+0.038 s,
of 1.2(-0.3,+0.3)x10^-4 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 5 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.50 (-0.10,+0.12)
and Ep = 858 (-375,+1067) keV (chi2 = 89/79 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -1.9
(chi2 = 89/78 dof).

The spectrum near the maximum count rate
(measured from T0 to T0+0.064 s)
is best fit in the 20 keV - 5 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.78 (-0.15,+0.17)
and Ep = 1532 (-359,+493) keV (chi2 = 25/29 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.2
(chi2 = 25/28 dof).

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


GRB_name: GRB141222A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17226
SUBJECT: Swift XRT and UVOT observations of GRB141222A
DATE:    14/12/23 19:34:00 GMT
FROM:    Massimiliano de Pasquale at IASF-Palermo  <mdp@ifc.inaf.it>

M. De Pasquale (IASF/INAF Palermo) and M. Siegel (PSU) report on behalf of the Swift-XRT team:

We have analysed 4.7 ks of XRT data for GRB 141222A, detected by the Fermi/LAT
(McEnery et al. GCN 17218), Fermi/GBM (Jenke et al., GCN 17220) and IPN (Svinkin et al.
GCN 17223), from 42.0 ks to 53.4 ks after the Fermi/LAT trigger. The data are entirely
in Photon Counting (PC) mode. No source is detected within the LAT error circle; we
determined a 3 sigma upper limit of 2.3e-3 count/s at the LAT coordinates.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020454.

The Swift/UVOT began settled observations of the field of GRB 141222
41986 s after the LAT trigger. No optical afterglow is detected in the initial UVOT
exposures within the LAT error circle. Preliminary 3-sigma upper limits using the
UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the
initial exposures are:

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

v        41986    53434     2510     >20.5
u        43226    50158     2375     >20.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.42 in the direction of the burst
(Schlegel et al. 1998).
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GRB_name: GRB141221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17227
SUBJECT: GRB 141221A: TAROT La Silla observatory optical observations
DATE:    14/12/24 14:38:04 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

Klotz A., Turpin D. (IRAP-CNRS-OMP),
Boer M., Gendre B., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA),
Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 141221A detected by SWIFT
(trigger 622006) with the TAROT robotic telescope (D=25cm)
located at the European Southern Observatory,
La Silla observatory, Chile.

The observations started 31.2s after the GRB trigger
(14.2s after the notice). The elevation of the field increased from
23 degrees above horizon and weather conditions
were good but the dawn interrupted the observations
after 41 minutes.

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect the optical counterpart between 31s
and 68s at a limiting magnitude Rlim = 16.6. Then
the end of the trail shows a sudden appearance of the
optical counterpart (cf. Sonbas et al. GCNC 17206).
Measures are:

  start    end  magnitude
  (sec)  (sec)
   31.2   68.5  Rlim = 16.6
   68.5   74.5  R = 16.0 +/- 0.2
   74.5   80.5  R = 15.7 +/- 0.2
   80.5   86.5  R = 15.5 +/- 0.2
   86.5   92.5  R = 15.6 +/- 0.3

Next images (in tracking mode) show the optical transcient:

  start    end  magnitude
  (sec)  (sec)  R    +/-
  104.6  134.6 15.47 0.03
  145.1  175.1 15.36 0.03
  185.7  215.7 15.40 0.03
  226.0  256.0 15.42 0.03
  266.3  296.3 15.39 0.03
  306.7  396.7 15.60 0.09
  401.3  491.3 16.17 0.02
  715.6  805.6 16.63 0.02
  816.2  906.2 16.68 0.08
1029.4 1119.4 16.95 0.08
1130   1525   17.22 0.08
1536   2486   17.82 0.08

The early afterglow observed by TAROT is compatible
with that observed by PROMPT (Trotter et al. GCNC
17210 and GCNC 17221).

Magnitudes were estimated with the nearby star
NOMAD-1 0982-0272573 R=12.23 and are not corrected
for galactic dust extinction.


GRB_name: GRB141221A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17228
SUBJECT: GRB 141221A: Keck spectroscopy
DATE:    14/12/25 13:26:00 GMT
FROM:    Daniel Perley at Caltech  <dperley@astro.caltech.edu>

D. A. Perley, Y. Cao (Caltech), and S. B. Cenko (GSFC) report:

We observed the optical afterglow of GRB 141221A (Sonbas et al., GCN 
17206) with the DEIMOS spectrograph on the Keck II telescope between 
12:48 and 13:10 UT on 2014-12-21.  Two 900-second exposures were 
acquired at high airmass.

We detect significant continuum flux across the entire spectral range 
between 4490-9660 Angstroms.  Inspection of the 1D spectrum shows two 
apparent absorption features at 6854 and 6873 Angstroms which we 
tentatively associate with the Mg II doublet at z=1.452. 
Lower-significance probable absorption lines are also seen at the 
wavelengths of the Fe II 2599, 2585, 2383, 2374, and 2344 lines at 
similar redshift, lending additional credence to this association. 
However, due to a failure of the blue arc calibration lamps, we note 
that our wavelength solution is preliminary and this result should be 
considered tentative.


GRB_name: GRB141225A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17229
SUBJECT: GRB 141225A: Swift detection of a burst
DATE:    14/12/25 23:28:25 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

P. D'Avanzo (INAF-OAB), A. P. Beardmore (U Leicester),
M. G. Bernardini (INAF-OAB), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), A. Y. Lien (GSFC/UMBC),
A. Melandri (INAF-OAB), C. J. Mountford (U Leicester) and
J. L. Racusin (NASA/GSFC) report on behalf of the Swift Team:

At 23:01:07 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 141225A (trigger=622476).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 138.751, +33.795 which is 
   RA(J2000) = 09h 15m 00s
   Dec(J2000) = +33d 47' 41"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 30 sec.  The peak count rate
was ~1600 counts/sec (15-350 keV), at ~6 sec after the trigger. 

The XRT began observing the field at 23:08:10.5 UT, 423.5 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 138.7782, 33.7919 which
is equivalent to:
   RA(J2000)  = 09h 15m 06.77s
   Dec(J2000) = +33d 47' 30.7"
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This
location is 82 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 (1.48 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 1.6
(+1.62/-1.47) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White
filter starting 440 seconds after the BAT trigger. No credible
afterglow candidate has been found in the initial data products.  The
8'x 8' 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 0.02. 

Merry Christmas from the Swift Team!

Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo 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: GRB141225A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17230
SUBJECT: GRB 141225A: 1.23m CAHA optical observations
DATE:    14/12/25 23:52:18 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

J. Gorosabel (IAA-CSIC/UPV-EHU), S. Hellmich (DLR), A. de Ugarte Postigo
(IAA-CSIC), S. Mottola (DLR), C. Thoene (IAA-CSIC), report on behalf of a
larger collaboration:

"We observed the field of GRB 141225A (D'Avanzo et al. GCN 17229) with the
1.23m CAHA telescope in the I-band starting at 23:07:27.7 UT (starting
~6.5 min post burst). We detected an optical source located at
RA(J2000)=09:15:06.93, DEC(J2000)=33:47:30.8 (+/-1") with a very
estimative magnitude of I~18.5 (Vega) consistent with the XRT position."


GRB_name: GRB141225A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17231
SUBJECT: GRB 141225A: LT optical candidate
DATE:    14/12/25 23:58:02 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

C. Guidorzi (U. Ferrara), J. Japelj (U. Ljubljana),
A. Melandri (INAF-OAB) on behalf of a large
collaboration reports:

The 2-m Liverpool Telescope automatically began
observing Swift GRB 141225A (D'Avanzo et al. GCN 17229).
Within the XRT error circle we found an uncatalogued
object at the following position:

RA(J2000) = 09:15:06.92
Dec(J2000)= +33:47:30.6

with r=20.3 +- 0.1 mag at 36 minutes post trigger,
calibrated against SDSS nearby stars.


GRB_name: GRB141225A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17232
SUBJECT: GRB 141225A: Optical aftergow confirmation
DATE:    14/12/26 00:05:51 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

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

We observed the field of GRB 141225A (D'Avanzo et al., GCN 17229) with 
the Nordic Optical telescope equipped with the MOSCA camera. 
Observations started at 23:25:08 UT (0.40 hr after the GRB trigger) and 
were conducted in the SDSS r band.

Consistent with the XRT position (see 
http://www.swift.ac.uk/xrt_positions/), we detect a bright source not 
present in the DSS, which is likely the optical afterglow of GRB 
141225A. Its coordinates are (J2000):

RA = 09:15:06.89
Dec = +33:47:30.8

and an approximate magnitude of R ~ 19.5 (Vega; assuming R = 16.2 for 
the USNO star at RA = 09:15:09.46, Dec = +33:47:48.7).

This is the same source reported by Gorosabel et al. (GCN 17230) and 
Guidorzi et al. (GCN 17231).


GRB_name: GRB141225A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17233
SUBJECT: GRB 141225A: UVOT detection
DATE:    14/12/26 02:16:13 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N.P.M. Kuin (MSSL/UCL) and P. D'Avanzo (INAF-OAB) report on behalf of the
Swift Team

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 427 seconds after the BAT trigger. There is a candidate afterglow
in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) =    09:15:06.92 = 138.77885
DEC(J2000) = +33:47:30.9 = 33.79191
with a 90%-confidence error radius of about 0.66 arc sec. This position is
2.3
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.66 with a 1-sigma error of about 0.08.
A second exposure of 150 seconds in the White filter starting 858 seconds
after
the BAT trigger has an estimated magnitude of 19.61 with a 1-sigma error of
about 0.16, showing a clear decay. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02.


GRB_name: GRB141225A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17234
SUBJECT: GRB 141225A: Redshift from OSIRIS at the 10.4m GTC
DATE:    14/12/26 03:08:38 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

J. Gorosabel (UPV-EHU, IAA-CSIC), A. de Ugarte Postigo (IAA-CSIC,
DARK/NBI), C.C. Thoene (IAA-CSIC),  N. Tanvir (U. Leicester), J.P.U. Fynbo
(DARK/NBI), D. Garca-Alvare (GTC), "A. Perez-Romero (GTC)
report on behalf of a larger collaboration:

We observed the afterglow of GRB 141225A (D'Avanzo et al. GCN 17229) with
OSIRIS at the 10.4m GTC. Observations began at 00:25:25 UT (~1.4 hours
post burst). Four 600s spectra were taken with the R1000B grism going from
3750 to 7800 AA. A first analisys based on archival arc lamps reveals
absorption features of FeII and MgII at a preliminary redshift of z=0.915.

[GCN OPS NOTE(27dec14): Pera author's request, D.G was changed to D.G-A
and A.P-R was added.]


GRB_name: GRB141225A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17235
SUBJECT: GRB 141225A: Enhanced Swift-XRT position
DATE:    14/12/26 04:07:30 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1893 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 141225A, 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 = 138.77827, +33.79184 which is equivalent
to:

RA (J2000): 09h 15m 6.79s
Dec (J2000): +33d 47' 30.6"

with an uncertainty of 1.6 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: GRB141225A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17236
SUBJECT: GRB 141225A: Nanshan very early optical observations
DATE:    14/12/26 06:39:37 GMT
FROM:    Dong Xu at DARK/NBI  <dong.dark@gmail.com>

D. Xu (DARK, NAOC) and X. Gao (Urumqi No.1 Senior High School, Xinjiang) report:

We observed the field of GRB 141225A (D'Avanzo et al., GCN 17229)
using the 36cm robotic telescope located at Nanshan, Xinjiang, China.
Observations started at 23:04:14 UT on 2014-12-25, i.e., 187 s after
the burst, and subsequently 3x40s, 4x60s, and 12x90s unfiltered images
were obtained.

The optical afterglow (Gorosabel et al., GCN 17230; Guidorzi et al.,
GCN 17231; Malesani et al., GCN 17232; Kuin & D'Avanzo, GCN 17233) is
detected in all 40s and 60s exposures and only in the beginnings of
90s exposures, and is evident of decaying. The afterglow has m(R)~17.2
from the first 40s image (i.e., 187 s - 227 s post-burst), calibrated
with R-band magnitudes of nearby SDSS stars.


GRB_name: GRB141225A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17237
SUBJECT: GRB 141225A: MASTER-SAAO first OT detection 
DATE:    14/12/26 10:41:39 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

D.Buckley, S. Potter, A. Kniazev, M. Kotze
South African Astronomical Observatory

E. Gorbovskoy,V. Lipunov, N.Tyurina P.Balanutsa, D.Denisenko, 
M.Pruzhinskaya,A.Kuznetsov, V.Kornilov, D.Kuvshinov, 
Lomonosov Moscow State University,
Sternberg Astronomical Institute

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina

MASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru)
installed several days ago  in South African Astronomical
Observatory (Sutherland) was automatically  pointed
to the  Swift and Fermi GRB 141225A (Avanzo  et. al. GCN 17229).
Firstly MASTER-SAAO pointed by FERMI coordinates and made first exposure 
28 sec. after FERMI trigger at  2014-12-25 23:02:28 UT.
Then MASTER-SAAO pointed to the  Swift coordinates 20 sec after  Swift 
notice time and 113 sec after trigger time at 2014-12-25 23:03:00 UT in 
two polarizations.

MASTER-SAAO discovered OT source (Gorosabel et. al. 17230, Malesani et. al 
17232, Kuin et. al 17233, Xu et. al 17236):

Ra:   09:15:06.94
Dec: +33:47:30.87
Mag:  17.5

The source is visible on the subsequent frames. The data reduction is 
continued.
Our  band  is well described by a parity 0.8R+0.2B (USNO B1).

This message may be cited.


GRB_name: GRB141225A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17238
SUBJECT: GRB 141225A: Swift-XRT refined Analysis
DATE:    14/12/26 14:28:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), J.A. Kennea
(PSU), V. Mangano (PSU), M.C. Stroh (PSU), K.L. Page (U. Leicester), C.
Pagani (U. Leicester), A.P. Beardmore (U. Leicester) and P. D'Avanzo
report on behalf of the Swift-XRT team:

We have analysed 8.0 ks of XRT data for GRB 141225A (D'Avanzo  et al.
GCN Circ. 17229),  from 434 s to 40.8 ks after the  BAT trigger. The
data comprise 33 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. 17235).

The light curve can be modelled with an initial power-law decay with an
index of alpha=2.22 (+0.32, -0.25), followed by a break at T+1770 s to
an alpha of 1.12 (+0.26, -0.38).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.67 (+0.13, -0.12). The
best-fitting absorption column is  consistent with the Galactic value
of 1.5 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 3.9 x 10^-11 (4.0 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.5 (+/-2.1) x 10^20 cm^-2
Galactic foreground: 1.5 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.67 (+0.13, -0.12)

If the light curve continues to decay with a power-law decay index of
1.12, the count rate at T+24 hours will be 1.9 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.3 x
10^-14 (7.4 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00622476.

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


GRB_name: GRB141225A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17239
SUBJECT: GRB 141225A: Swift-BAT refined analysis
DATE:    14/12/26 14:29:58 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), P. D'Avanzo (INAF-OAB), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (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 141225A (trigger #622476)
(D'Avanzo, et al., GCN Circ. 17229).  The BAT ground-calculated position is
RA, Dec = 138.754, 33.774 deg which is
    RA(J2000)  =  09h 15m 01.1s
    Dec(J2000) = +33d 46' 27.7"
with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 26%.

The burst location first entered the BAT field of view at ~T-40 sec, during a
pre-planned slew.  The mask-weighted light curve shows a single FRED-shaped
peak, beginning at T+5 sec, peaking at T+12 sec and returning to baseline level
by T+50 sec.  T90 (15-350 keV) is 40.24 +- 7.04 sec sec (estimated error 
including systematics).

The time-averaged spectrum from T+5.50 to T+50.68 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.32 +- 0.15.  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+11.76 sec in the 15-150 keV band is 
1.3 +- 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/622476/BA/


GRB_name: GRB141225A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17240
SUBJECT: GRB 141225A: very early T60 observations
DATE:    14/12/26 16:15:01 GMT
FROM:    Eda Sonbas at NASA/GSFC  <edasonbas@gmail.com>

E. Sonbas (Adiyaman Univ.), T. Guver (Istanbul Univ.), E. Gogus (Sabanci
Univ.), M. Parmaksizoglu, M. Dindar, H. Kirbiyik (TUG) report on behalf of
a larger collaboration


 We observed the field of Swift GRB 141225A (D'Avanzo et al., GCN#17229)
with the 0.60 meter robotic T60 telescope (Dindar et al. 2014; Bakirlitepe,
TUBITAK National Observatory, Turkey), starting December, 25, 23:03:16.37
UT (~ 129 second after the trigger). Observations were carried out with the
R and B filters. The afterglow (Gorosabel et al., GCN 17230; Guidorzi et
al., GCN 17231; Malesani et al., GCN 17232; Kuin & D'Avanzo, GCN 17233, Xu
et al. GCN 17236, Buckley et al. GCN 17237) is clearly detected in the R
band images with an exposure time of 60 s.


Using USNO-B1 star USNO-B1 1237-0186662 (R.A.=138.789, Dec=+33.797) in the
field, the R magnitudes of the OT were estimated as follows;


t-t0 (sec) exp.(s) filt mag err (+/-)

~129 60 R 17.04 0.04

~195 60 R 17.15 0.02


Further analysis are ongoing.


We are grateful to TUBITAK National Observatory for a partial support in
using T60 telescope with project number 539 and technical support.


GRB_name: GRB141225A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17241
SUBJECT: GRB 141225A: Fermi GBM detection
DATE:    14/12/26 17:48:26 GMT
FROM:    Peter Jenke at MSFC  <peter.a.jenke@nasa.gov>

P. Jenke (UAH) reports on behalf of the Fermi GBM Team:

"At 23:01:13.82 UT on December 25 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 141225A (trigger 441241276/141225959),
which was also detected by 
Swift (P. D'Avanzo et al. 2014, GCN 17229).  Additionally,
there were optical detections from the 1.23m CAHA telescope
 (J. Gorosabel et al. 2014 GCN 17230) among others as well
 as a redshift measurement (J. Gorosabel et al. 2014 GCN 17234).
The GBM on-ground location, using the Fermi GBM trigger
data, is consistent with the Swift/XRT and optical locations.  

The angle of the burst direction to the Fermi LAT boresight
 is 104 degrees.

The GBM light curve consists of one FRED-like peak with a 
duration (T90) of about 56 s (50-300 keV).
The time-averaged spectrum from T0-4.1s to T0+21.5s 
is well fit by a Band function with Epeak = 187 +/- 29 keV, 
Alpha = -0.35 +/- 0.17 and Beta = -2.0 +/- 0.1. 

The event fluence (10-1000 keV) in this time interval is
(6.5 +/- 0.3)E-06 ergs/cm^2. The 1.0-sec peak photon flux measured
starting from T0+9.7s in the 10-1000 keV band
is 2.5 +/- 0.2 ph/s/cm^2.

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


GRB_name: GRB141225A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17242
SUBJECT: GRB 141225A: Swift/UVOT refined analysis
DATE:    14/12/26 18:37:57 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and P. D'Avanzo (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 141225A
428 s after the BAT trigger (D'Avanzo et al., GCN Circ. 17229). The optical
afterglow has been reported (Gorosabel et al, GCN Circ. 17230; Guidorzi et
al.,
GCN Circ. 17231; Malesani et al., GCN Circ. 17232; Kuin & D'Avanzo,
GCN.Circ.
17233; Xu et al., GCN Circ. 17236; Buckley et al., 17237; Sonbas et al.,
GCB
Circ. 17240) with a redshift of z=0.915 (Gorosabel et al., GCN Circ. 17234).

Preliminary detections and 3-sigma upper limits using the UVOT photometric
system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

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

white              428          578          147         18.81 +/- 0.06
white              858         1008          147         19.76 +/- 0.10
v                  735         1406           78        >19.2
b                  660         1495           86        >19.5
u                  636         1481           97         19.19 +/- 0.19
w1                 611         1456           97        >19.0
m2                 760          780           19        >18.6
w2                6480         6680          197        >19.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB141225A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17243
SUBJECT: GRB 141225A: TAROT Calern observatory optical observations
DATE:    14/12/27 00:45:35 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

Klotz A. (IRAP-CNRS-OMP), Gendre B. (IRAP-CNRS-OMP),
Boer M., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA),
Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 141225A detected by SWIFT
(trigger 513505) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 8.2 min after the GRB trigger.
The elevation of the field increased from
50 degrees above horizon and weather conditions
were good.

We co-added a series of exposures to measure the optical
afterglow discovered by Gorosabel et al. (GCNC 17230):

Tstart Tend
(sec)  (sec) Rmag +/-
  496    907  18.8 0.3
  918   1315  19.0 0.3
1327   1728  19.9 0.5

The afterglow is no longer detected in the next images.

Magnitudes were estimated using USNO-B1 star USNO-B1 1237-0186662
(R.A.=138.789, Dec=+33.797) as Sonbas et al. (GCNC 17240).
Magnitudes are not corrected for galactic dust extinction.


GRB_name: GRB141225A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17244
SUBJECT: GRB 141225A: MITSuME Okayama upper limits
DATE:    14/12/27 04:27:31 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 MITSuME and OISTER collaboration:

We observed the field of GRB 141225A (D'Avanzo et al., GCNC 17229)
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 2014-12-26 18:53:27 UT (~19.9 h after the burst).
We could not detect the previously reported afterglow (Gorosabel et al., GCNC
17230; Guidorzi et al., GCNC 17231) in all the three bands.

Three sigma upper limits of the OT are listed below.
We used SDSS-DR8 catalog for flux calibration.

#T0+[day]  MID-UT    T-EXP[sec]   g'     Rc     Ic
-----------------------------------------------------
0.68285    15:24:25    3780.0   >19.7  >19.6  >19.0
-----------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]


GRB_name: GRB141225A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17245
SUBJECT: GRB 141225A: MASTER-SAAO OT light curve 
DATE:    14/12/28 12:16:57 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

D.Buckley, S. Potter, A. Kniazev, M. Kotze
South African Astronomical Observatory

E. Gorbovskoy,V. Lipunov, N.Tyurina, P.Balanutsa, D.Denisenko, 
M.Pruzhinskaya, A.Kuznetsov, V.Kornilov, D.Kuvshinov,
Lomonosov Moscow State University, Sternberg Astronomical Institute

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina

MASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru)
installed several days ago  in South African Astronomical
Observatory (Sutherland) was automatically  pointed
to the  Swift and Fermi GRB 141225A (Avanzo  et. al. GCN 17229).
Firstly MASTER-SAAO pointed by FERMI coordinates and made first exposure 28 
sec after FERMI trigger at  2014-12-25 23:02:28 UT (Buckley et al., 
17233).
Then MASTER-SAAO pointed to the  Swift coordinates 20 sec after  Swift notice 
time and 113 sec after trigger time at 2014-12-25 23:03:00 UT.

The results of our photometery are:

   Start   T-T_mid  Exp.  Mag   Coadd

   UT         s      s    unf    ?

23:03:00    123    20    17.1   no
23:03:34    161    30    17.3   no
23:04:15    207    40    17.5   no
23:05:05    263    50    17.7   no
23:06:06    329    60    18.9   no
23:07:17    405    70    18.7   no
23:08:38    556   200    19.0    2
23:12:19    823   290    19.8    2
23:17:31   3161  3600    21.3   20



Our  band  is well described by a parity 0.8R+0.2B (USNO B1).
The light curve from 113 to 300 power low index is about
  alpha ~= 0.76+-0.10  (F ~ t_-alpha)

and alpha =~ 1.51 from 400 to 1500 .
We see ~1 magnitude depression  at 329 sec.

The magnitudes in the table are not corrected for the Galactic extinction
because its less than the our errors (Schlegel et al. 1998).

The light curve is available at 
http://master.sai.msu.ru/static/GRB/GRB141225A.png

This message may be cited.


GRB_name: GRB141229A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17246
SUBJECT: GRB 141229A: MAXI/GSC detection
DATE:    14/12/29 13:14:51 GMT
FROM:    H. Negoro at Nihon U.  <negoro@phys.cst.nihon-u.ac.jp>

M. Fujita, H. Negoro (Nihon U.), M. Serino (RIKEN), S. Ueno, H. Tomida, 
S. Nakahira, M. Kimura, M. Ishikawa, Y. E. Nakagawa (JAXA), 
T. Mihara, M. Sugizaki, M. Morii, J. Sugimoto, T. Takagi, A. Yoshikawa, 
M. Matsuoka (RIKEN), N. Kawai, Y. Tachibana, T. Yoshii (Tokyo Tech), 
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU), 
H. Tsunemi, D. Uchida (Osaka U.), M. Nakajima, K. Fukushima, T. Onodera, 
K. Suzuki, F. Honda, T. Namba (Nihon U.), Y. Ueda, M. Shidatsu, T. Kawamuro, 
T. Hori (Kyoto U.), Y. Tsuboi, A. Kawagoe (Chuo U.), 
M. Yamauchi, Y. Morooka, D. Itoh (Miyazaki U.), K. Yamaoka (Nagoya U.)

The MAXI/GSC nova-alert system triggered a bright uncatalogued X-ray 
transient source at UT 11:49:02 on 2014 December 29. 
We obtain a rectangular error box for the transient source with the following 
corners:

(R.A., Dec) = (71.479 deg, -18.956 deg) = (04 45 54, -18 57 20) (J2000)
(R.A., Dec) = (71.846 deg, -18.494 deg) = (04 47 22, -18 29 38) (J2000)
(R.A., Dec) = (72.599 deg, -19.778 deg) = (04 50 23, -19 46 41) (J2000)
(R.A., Dec) = (72.961 deg, -19.311 deg) = (04 51 50, -19 18 40) (J2000)

There is an additional systematic uncertainty of 0.1 deg (90% containment 
radius). The X-ray flux averaged over the scan was 179 +- 29 mCrab 
(4-10keV, 1 sigma error).
There was no significant excess flux in the previous transit at UT 10:16.


GRB_name: GRB141229A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17247
SUBJECT: GRB 141229A Tiled Swift observations
DATE:    14/12/29 14:51:10 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
Fermi/GBM GRB 141229A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00036

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the Fermi/GBM event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; and 2009, MNRAS, 397, 1177).

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


GRB_name: GRB141225A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17248
SUBJECT: Christmas GRB 141225A: GROND Observations
DATE:    14/12/29 16:59:03 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann (TLS Tautenburg), P. Schady, and J. Greiner (both MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 141225A (Swift trigger 622476; D'Avanzo et
al., GCN #17229) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started at 05:58 UT on 26 December 2014, around 7 hours after
the  GRB trigger. They were performed at an average seeing of 1".4 and at
an average airmass of 2.3.

Based on images with exposure times of 2640 s in g'r'i'z' and 2400 s in
JHK, we detect the afterglow (Gorosabel et al., GCN #17230, Guidorzi et
al., GCN #17231) at the following AB magnitudes:

g' = 22.56 +/- 0.07 mag,
r' = 22.31 +/- 0.07 mag,
i' = 22.34 +/- 0.14 mag,
z' = 21.74 +/- 0.12 mag,
J  > 21.5 mag,
H  > 21.0 mag, and
K  > 17.3 mag.

The colors do not point to a strongly extinguished afterglow, implying it
is intrinsically faint.

The given magnitudes and limits are derived based on calibrating the
images against SDSS (g'r'i'z') and 2MASS field stars (JHK) and are not
corrected for the Galactic foreground extinction corresponding to a
reddening of E_(B-V)= 0.017 in the direction of the burst (Schlegel et al.
1998).


GRB_name: GRB141229A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17249
SUBJECT: GRB 141229A: Fermi GBM detection
DATE:    14/12/29 18:58:55 GMT
FROM:    Oliver Roberts at UCD/Fermi  <oliver.roberts@ucd.ie>

O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:

"At 11:48:59.84 UT on the 29th of December 2014, the Fermi
Gamma-Ray Burst Monitor triggered and located GRB 141229A
(trigger 441546542 / 141229492 ). The GBM on-ground location,
using the Fermi GBM trigger data, is consistent with the
MAXI/GSC position (Negoro et al. 2014, GCN 17246).

The angle from the Fermi LAT boresight is about 104 degrees.

The GBM light curve consists of a single FRED-like peak with
a duration (T90) of about 11 seconds (50-300 keV). The time-
averaged spectrum from T0+0.0 to T0+11 seconds is adequately
fit by a power law function with an exponential high-energy
cutoff. The power law index is -0.91 +/- 0.08 and the cutoff
energy, parameterized as Epeak, is 275 +/- 31 keV.

The event fluence (10-1000 keV) in this time interval is
(5.1 +/- 0.4)E-06  erg/cm^2. The 1-sec peak photon flux
measured starting from T0-0.1 s in the 10-1000 keV band
is 8.9 +/- 0.3 ph/s/cm^2.

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


GRB_name: GRB141229A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17251
SUBJECT: GRB 141229A: Swift-XRT observations
DATE:    14/12/30 00:34:12 GMT
FROM:    Maria Grazia Bernardini at INAF/Brera  <grazia.bernardini@brera.inaf.it>

M.G. Bernardini, A. Melandri, P. D'Avanzo (INAF-OAB) & P. A. Evans (U. 
Leicester)
report on behalf of the Swift-XRT team:

Swift XRT has observed the error circle of GRB 141229A, detected
by MAXI/GSC (Fujita et al., GCN 17246) and Fermi/GBM (Roberts, GCN 17249)
in a series of observations tiled on the sky. The total exposure time is
6.6 ks spread over 7 fields. The observations started 11.7 ks after the
Fermi/GBM trigger.
Within these data we detect a possibly fading, uncatalogued X-ray source at
RA, Dec=72.42830, -19.23282 which is equivalent to:
   RA (J2000)    = 04h 49m 42.79s
   Dec (J2000) = -19Â° 13â€² 58.1â€²â€²
with an uncertainty of 4.7 arcsec (radius, 90% confidence). The
exposure at this location was 1.4 ks. With the present uncertainties,
a secure identification of the afterglow is not possible.

The results of the automatic processing for this source are available
at http://www.swift.ac.uk/xrt_products/TILED_GRB00036/index_2.php

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


GRB_name: GRB141229A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17252
SUBJECT: GRB 141229A: Nanshan optical upper limit
DATE:    14/12/30 02:12:25 GMT
FROM:    Dong Xu at DARK/NBI  <dong.dark@gmail.com>

D. Xu (DARK, NAOC), H.-B. Niu, A. Esamdin, L. Ma (XAO) report:

We observed the field of MAXI-detected GRB 141229A (Fujita et al., GCN
17246), using the 1m optical telescope located at Nanshan, Xinjiang,
China, which has a field of view of 1.3x1.3 deg^2. Two epochs of 300s
R-band images were obtained at 15:26:23 UT and 18:36:14 UT on
2014-12-29, respectively. No optical source was detected at the XRT
position reported in Bernardini et al. (GCN 17251), down to a limiting
magnitude of R=20.5.


GRB_name: GRB141229A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17253
SUBJECT: GRB 141229A: 1.23m CAHA optical observations
DATE:    14/12/30 02:14:22 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

J. Gorosabel (IAA-CSIC/UPV-EHU), S. Hellmich (DLR), S. Mottola (DLR),
report on behalf of a larger collaboration:

We used the 1.23m CAHA telescope to image the XRT source (Benardini et al.
GCN 17251) detected in the GRB 141229A field (Fujita et al. GCN 17246;
Evans et al. GCN 17247; Roberts et al. GCN 17249). The observations were
carried out in the I-band starting on Dec 29.93278 UT (~10.6 hours post
GRB). No object brighter than I~21 (Vega) is detected within the XRT error
circle.


GRB_name: GRB141230A
Detection_method: iPTF
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17254
SUBJECT: GRB 141230A: iPTF Optical Observations and Candidate Afterglow iPTF14jko
DATE:    14/12/30 08:28:03 GMT
FROM:    Leo Singer at CIT/PTF  <lsinger@caltech.edu>

L. P. Singer (NASA/GSFC), S. B. Cenko (NASA/GSFC), and M. M. Kasliwal
(Carnegie Observatories/Princeton) report on behalf of the intermediate
Palomar Transient Factory (iPTF) collaboration:

Fermi GBM detected GRB 141230A (Fermi trigger 441602665 / bn141230142) at
2014-12-30 03:24:22.64. We searched for optical counterparts using the
Palomar 48-inch Oschin telescope (P48), imaging 20 fields spanning an area
of 147 deg2, covering about half of the 1-sigma statistical+systematic
region of the final Fermi GBM localization and part of the 2-sigma region.
Based on the GBM localization, we estimate a 43% prior probability that
these fields contain the true location of the source.

Sifting through candidate variable sources using image subtraction and
standard iPTF vetting procedures, we detect the optical transient
iPTF14jko, at the coordinates:
  RA(J2000)  =  4h 08m 41.48s (62.172836 deg)
  Dec(J2000) = -6d 40' 36.0"  (-6.676663 deg)
No source is detectable at this location in SDSS images. The last iPTF
survey visit was on September 16. We report the following P48 photometry:
  -104.7 day:   R > 20.12
  +54.80 min:   R = 19.91 +/- 0.11
  +129.9 min:   R = 19.75 +/- 0.14
The source does not appear to be fading at this time. Times are relative
to the GBM trigger. Magnitudes are in the Mould R filter and in the AB
system, calibrated with respect to point sources in SDSS as described in
Ofek et al. (2012, http://dx.doi.org/10.1086/664065).

We also detect the optical transient iPTF14jkn, at the coordinates:
  RA(J2000)  =  3h 55m 02.59s (58.760779 deg)
  Dec(J2000) = -6d 44' 04.2"  (-6.734503 deg)
We note that this position is near the bright (r = 13.59 mag) star,
SDSS J035501.84-064404.9. We report our P48 photometry:
  -104.7 day:   R > 20.34
  +98.02 min:   R = 19.60 +/- 0.10
Poor seeing conditions may call into question the veracity of this optical
transient and the accuracy of its photometry.

We have submitted a Swift TOO for iPTF14jko. Further observations are
encouraged to determine the nature of the source.

The diagram http://www.its.caltech.edu/~lsinger/iptf/Fermi441602665.pdf
shows our P48 fields and the location of the optical transient candidates
in relation to the Fermi GBM 1- and 2-sigma statistical+systematic
contours.


GRB_name: GRB141230A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17255
SUBJECT: GRB 141230A: Nanshan optical obsrvations
DATE:    14/12/30 15:36:22 GMT
FROM:    Dong Xu at DARK/NBI  <dong.dark@gmail.com>

D. Xu (DARK, NAOC), H.-B. Niu, A. Esamdin, L. Ma (XAO) report:

We observed the field of iPTF14jko (Singer et al., GCN 17254), a
candidate optical afterglow of GRB 141230A (Fermi trigger 441602665 /
bn141230142), using the 1m telescope located at Nanshan, Xinjiang,
China. We obtained 2x120s R-band images at 13:40 UT on 2014-12-30
(i.e., ~10.3 hr post-burst).

A source is detected at the iPTF14jko position with m(R)=19.53+/-0.28
(Vega), calibrated with nearby SDSS stars. The source basically
remains constant compared with the early (129.9 min post-burst)
measurement in GCN 17254, which indicates that it is unlikely the
optical afterglow of GRB 141230A, according to the decaying behavior
of conventional GRB optical light curves.


GRB_name: GRB141229A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17256
SUBJECT: GRB 141229A Swift-BAT observations
DATE:    14/12/30 18:33:53 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

J. R. Cummings, S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):


GRB 141229A (Fujita et al., GCN 17246) occurred during a preplanned Swift slew
maneuver.  A mosaic of BAT images at the time of the burst contains a
significant source consistent with the XRT afterglow position (Bernardini
et al., GCN 17251).  The partial coding was 6%.

The mask-weighted light curve shows a single FRED-shaped peak.  T90 (15-350 keV)
is 7 +- 1 sec (estimated error including systematics).

The time-averaged spectrum in 8 seconds is best fit by a simple power-law model.
The power law index of the time-averaged spectrum is 1.29 +- 0.17.  The fluence
in the 15-150 keV band is 1.5 +- 0.3 x 10^-6  erg/cm2.  The 1-sec peak photon flux
measured in the 15-150 keV band is 1.2 +- 0.5 ph/cm2/sec.  All the quoted errors
are at the 90% confidence level.

Since this burst was not detected onboard, the usual automated BAT data
products are not available.


GRB_name: GRB141230A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17257
SUBJECT: GRB 141230A: Fermi GBM detection
DATE:    14/12/30 19:13:43 GMT
FROM:    Oliver Roberts at UCD/Fermi  <oliver.roberts@ucd.ie>

O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:

"At 03:24:22.64 UT on the 30th of December 2014, the Fermi
Gamma-Ray Burst Monitor triggered and located GRB 141230A
(trigger 441602665 / 141230142 ). The GBM on-ground location,
using the Fermi GBM trigger data, is RA = 57.0, Dec =+1.6,
with an uncertainty of 3.3 degrees (radius, 1-sigma
containment,statistical only; there is additionally a
systematic error which is currently estimated to be 2 to
3 degrees).

The angle from the Fermi LAT boresight is about 120 degrees.

The GBM light curve consists of a single FRED-like peak with
a duration (T90) of about 9.9 s (50-300 keV). The time-averaged
spectrum from T0+0.0 s to T0+5.1 s is well fit by a power law
function with an an exponential high-energy cutoff. The power
law index is -1.51 +/- 0.19 and the cutoff energy, parameterized
as Epeak, is 75 +/- 16 keV. The event fluence (10-1000 keV) in
this time interval is (1.2 +/- 0.1)E-06  erg/cm^2. The 1-sec peak
photon flux measured starting from T0+0.1 s in the 10-1000 keV
band is 8.4 +/- 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: GRB141230A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17258
SUBJECT: Swift-XRT and UVOT follow-up of iPTF14jko (GRB 141230A)
DATE:    14/12/30 23:26:05 GMT
FROM:    Andrea Melandri at INAF-OAB  <andrea.melandri@brera.inaf.it>

A. Melandri, M.G. Bernardini, P. DAvanzo (INAF-OAB), F. E. Marshall (NASA/GSFC), P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift team:

We have analysed 3 ks of Swift-XRT data for the optical transient iPTF14jko (Singer et al., GCN 17254) within the error circle of the Fermi/GBM GRB 141230A (Roberts, GCN Circ. 17257), from 29.2 ks to 41.9 ks after the GBM trigger. The data are all in Photon Counting (PC) mode. No X-ray afterglow is detected at the position of the iPTF14jko optical source reported by Singer et al. (GCN Circ 17254). The 3-sigma upper limit is 3.3 x 10^-3 cts/s.

The Swift-UVOT began settled observations of the field of GRB 141230A about 29.2 ks after the GBM trigger. No optical afterglow consistent with the optical position (Singer et al. GCN Circ. 17254) is detected in the initial UVOT exposures.The preliminary 3-sigma upper limit using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures is:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
w2               29202        41957         2928         >21.8

The magnitude in the table is 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: GRB141229A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17259
SUBJECT: GRB 141229A: Deep MASTER inspection
DATE:    14/12/31 09:50:02 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

E. Gorbovskoy,V. Lipunov,  P.Balanutsa, D.Denisenko,
M.Pruzhinskaya,A.Kuznetsov, V.Kornilov, D.Kuvshinov, N.Tyurina
Lomonosov Moscow State University,
Sternberg Astronomical Institute


D.Buckley, S. Potter, A. Kniazev
South African Astronomical Observatory

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina


MASTER-Kislovodsk robotic telescope (in Russia) was pointed to MAXI 
GRB141229A (Fujita et al., GCN 17246) error box after 5 hours (direktly 
after error box arises at 2014-12-29 16:46:38 UT.

MASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
instaleted   in South African Astronomical Observatory (Sutherland) 
automaticaly was pointed to the  MAXI GRB141229A (Fujita et al., GCN 
17246)  after sun set    at 2014-12-29 20:57:10 UT (9 hours 
after trigger time) in unfiltered regime.

There is no any optical transients inside Swift XRT
error box (Bernardini et al., GCN 17251).

Our upper limits on Kislovodsk and SAAO observatiories available in Table 
1.

Table 1.
   Date       Time (start)  T_trig-Tmid  Expt.  Site.  Mlim  Coadd
                 UT             s
2014-12-29  16:46:38.543     19531      2160    KIS    19.6   12
2014-12-29  20:57:10.861     34986      3600   SAAO    22.3   20

MASTER-SAAO image available here:
http://master.sai.msu.ru/static/GRB/MASTER_SAAO_GRB141225A.png


This message may be cited.


GRB_name: GRB141229A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17260
SUBJECT: Konus-Wind observation of GRB 141229A
DATE:    14/12/31 12:06:31 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

The long-duration GRB 141229A
(MAXI/GSC detection: Fujita et al., GCN Circ. 17246;
Fermi-GBM observation: Roberts, GCN Circ. 17249;
Swift-BAT observation: Cummings, GCN Circ. 17256)
triggered Konus-Wind at T0=42542.652 s UT (11:49:02.652).

The burst light curve shows a single pulse with a duration of ~7.6 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB141229_T42542/

As observed by Konus-Wind, the burst
had a fluence of 4.7(-0.6,+0.8)x10^-6 erg/cm2,
and a 64-ms peak flux, measured from T0+0.064 s,
of 4.6(-1.3,+1.3)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.03 (-0.22,+0.25)
and Ep = 254 (-51,+86) keV (chi2 = 82/97 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.3
(chi2 = 82/96 dof)

The spectrum near the maximum count rate
(measured from T0+0.000 to T0+0.256 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = 0.3 (-0.5,+0.7)
and Ep = 407 (-71,+101) keV (chi2 = 35/36 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.4
(chi2 = 35/35 dof)

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


GRB_name: GRB150101A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17261
SUBJECT: GRB 150101A: Swift detection of a short burst
DATE:    15/01/01 06:53:33 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

A. Vargas (PSU), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (NASA/UMBC), H. A. Krimm (CRESST/GSFC/USRA),
B. Sbarufatti (INAF-OAB/PSU) and M. H. Siegel (PSU) report on behalf
of the Swift Team:

At 06:28:53 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150101A (trigger=623158).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 312.631, +36.728 which is 
   RA(J2000) = 20h 50m 31s
   Dec(J2000) = +36d 43' 39"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 0.1 sec.  The peak count rate
was ~3700 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 06:29:54.4 UT, 60.9 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 312.6038, 36.7334 which
is equivalent to:
   RA(J2000)  = 20h 50m 24.91s
   Dec(J2000) = +36d 44' 00.3"
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 80 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 4.62
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 65 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 8'x8'
region for the list of sources generated on-board 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
 region. No correction has been made for the large, but uncertain
extinction  expected. 

Burst Advocate for this burst is A. Vargas (vargas.09242011.angie 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: GRB150101A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17262
SUBJECT: GRB 150101A: Enhanced Swift-XRT position
DATE:    15/01/01 09:49:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1496 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 150101A, 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 = 312.60337, +36.73318 which is equivalent
to:

RA (J2000): 20h 50m 24.81s
Dec (J2000): +36d 43' 59.5"

with an uncertainty of 2.7 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: GRB150101A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17263
SUBJECT: GRB 150101A: Swift/UVOT Upper Limits
DATE:    15/01/01 16:27:00 GMT
FROM:    Frank Marshall at GSFC  <femarsha@khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and A. Vargas (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150101A
65 s after the BAT trigger (Vargas et al., GCN Circ. 17261).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 17262)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposures and subsequent exposures are:

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

white_FC            65          215          147         >21.4
u_FC               277          527          246         >20.6
white               65         1524          392         >22.1
v                  607         1574          117         >20.1
b                  533         1500           97         >20.4
u                  277         1475          324         >21.0
w1                 656         1451           97         >19.4
m2                 631         1425           97         >19.9
w2                 583         1550          117         >20.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.52 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150101A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17264
SUBJECT: GRB 150101A: Swift-XRT refined Analysis
DATE:    15/01/01 18:53:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

B. Sbarufatti (INAF-OAB/PSU), V. Mangano (PSU), M.C. Stroh (PSU), D.N.
Burrows (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester),
P.A. Evans (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC) and
A. Vargas report on behalf of the Swift-XRT team:

We have analysed 8.5 ks of XRT data for GRB 150101A (Vargas  et al. GCN
Circ. 17261),  from 68 s to 18.8 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. 17262). The source
is fading with alpha >0.6.


If the light curve continues to decay with a power-law decay index of ,
the count rate at T+24 hours will be 7.9 x 10^-5 count s^-1

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00623158.

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


GRB_name: GRB150101A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17265
SUBJECT: GRB 150101A: Fermi GBM detection
DATE:    15/01/01 19:47:05 GMT
FROM:    Oliver Roberts at UCD/Fermi  <oliver.roberts@ucd.ie>

O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:

"At 06:28:53.76 UT on the 1st of January 2015, the Fermi
Gamma-Ray Burst Monitor triggered and located GRB 150101A
(trigger 441786536 / 150101270). The GBM on-ground location,
using the Fermi GBM trigger data, is consistent with the
enhanced Swift XRT position (Goad et al. 2015, GCN 17262).

The angle from the Fermi LAT boresight is about 12 degrees.

The GBM light curve consists of a single quick pulse with
a duration (T90) of about 0.24 s (50-300 keV). The
time-averaged spectrum from T0-0.13 s to T0+13 s is
adequately fit by a power law function. The power law index is
 -1.5 +/- 0.1. The event fluence (10-1000 keV) in this time
interval is (9.9 +/- 2.0)E-08  erg/cm^2. The 64 ms peak
photon flux measured starting from T0-0.1 s in the
10-1000 keV band is 5.3 +/- 1.1 ph/s/cm^2.

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


GRB_name: GRB150101A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17266
SUBJECT: GRB 150101A Swift-BAT refined analysis of the short hard burst
DATE:    15/01/02 21:19:17 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC),  J. R. Cummings,
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
  
Using the data set from T-240 to T+962 sec, we report further analysis
of BAT GRB 150101A (trigger #623158) (Vargas, et al., GCN Circ. 17261).
The BAT ground-calculated position is RA, Dec = 312.599, 36.669 deg which is
    RA(J2000)  =  20h 50m 23.6s
    Dec(J2000) = +36d 40' 07.8"
with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 91%.
  
The mask-weighted light curve shows a single peak.  T90 (15-350 keV) is
0.060 +- 0.005 sec (estimated error including systematics).
  
The time-averaged spectrum from T+0.0 to T+0.68 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.26 +- 0.31.  The fluence in the 15-150 keV band is
(2.3 +- 0.5) x 10^-08 erg/cm2.  The 1-sec peak photon flux measured from
T-0.46 sec in the 15-150 keV band is 0.3 +- 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/623158/BA/


GRB_name: GRB150103A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17269
SUBJECT: GRB 150103A: Swift detection of a burst
DATE:    15/01/03 20:17:37 GMT
FROM:    Neil Gehrels at GSFC  <gehrels@milkyway.gsfc.nasa.gov>

L. M. Z. Hagen (PSU), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), M.E. Gropp (PSU), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA) and M. H. Siegel (PSU) report on behalf
of the Swift Team:

At 20:02:18 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150103A (trigger=623368).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 131.639, -48.890 which is 
   RA(J2000) = 08h 46m 33s
   Dec(J2000) = -48d 53' 24"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single peak about
40 seconds long.  The peak count rate was ~875 counts/sec (15-350 keV), 
at ~5 sec after the trigger. 

The XRT began observing the field at 20:04:29.5 UT, 130.5 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 131.66761, -48.88595 which is
equivalent to:
   RA(J2000)  = 08h 46m 40.23s
   Dec(J2000) = -48d 53' 09.4"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 69 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 8.96
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 135 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 large, but uncertain extinction expected. 

Burst Advocate for this burst is L. M. Z. Hagen (lea.zernow.hagen 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: GRB150103A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17270
SUBJECT: GRB 150103A: Prompt enhanced Swift-XRT position
DATE:    15/01/03 20:37:39 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Using  promptly downlinked XRT event data for GRB 150103A, we find an
enhanced XRT position of the afterglow: RA, Dec: 131.6663, -48.8863
which is equivalent to:
   RA (J2000)  = 08 46 39.92
   Dec (J2000) = -48 53 10.6
with an uncertainty of 2.0 arcseconds (radius, 90% confidence).
Analysis of the promptly available data is online at
http://www.swift.ac.uk/sper/623368.

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: GRB150103A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17272
SUBJECT: GRB 150103A: Enhanced Swift-XRT position
DATE:    15/01/03 22:59:18 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1050 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 150103A, 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 = 131.66600, -48.88593 which is equivalent
to:

RA (J2000): 08h 46m 39.84s
Dec (J2000): -48d 53' 09.4"

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: GRB150103A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17273
SUBJECT: GRB 150103A: Zadko observatory - Gingin optical observations
DATE:    15/01/04 00:47:23 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

A. Klotz, D. Turpin (IRAP-CNRS-OMP), D. Macpherson (UWA/ICRAR), D. 
Coward (UWA),
M. Boer, B. Gendre, K. Siellez, H. Dereli, O. Bardho (UNS-CNRS-OCA),
A. Williams (PO-UWA), R. Martin (PO-UWA) report:

We imaged the field of GRB 150103A detected by SWIFT
(trigger 623368) with the Zadko robotic telescope (D=100cm)
located at the observatory - Gingin, Australia.

The observations started 121.6s after the GRB trigger
(44.7s after the notice). The elevation of the field decreased
from 62 degrees above horizon and weather conditions
were good but during the dawn.

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT in the XRT error box provided by
Osborne et al. (GCNC 17272) with a limiting magnitude of:

t0+121.6s to t0+181.6s : Rlim = 16.7

The second image is 30.0s exposure in tracking mode:

t0+200.0s to t0+230.0s : Rlim = 18.9

The following images give the same limits:
t0+239s to t0+347s : Rlim = 18.9

Images taken later are saturated due to the dawn.

Magnitudes were estimated with the nearby NOMAD1 stars
and are not corrected for galactic dust extinction.


GRB_name: GRB150103A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17274
SUBJECT: GRB 150103A: Swift-BAT refined analysis
DATE:    15/01/04 01:59:55 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

J. R. Cummings, S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(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 150103A (trigger #623368) (Hagen, et al.,
GCN Circ. 17269).  The BAT ground-calculated position is
RA, Dec = 131.674, -48.896 deg which is
    RA(J2000)  =  08h 46m 41.9s
    Dec(J2000) = -48d 53' 45.2"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 67%.
  
The mask-weighted light curve shows a single broad peak.  T90 (15-350 keV) is
49.1 +- 9.8 sec (estimated error including systematics).
  
The time-averaged spectrum from T+6.06 to T+64.68 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index -0.03 +- 1.01,
and Epeak of 54.2 +- 12.8 keV (chi squared 54.70 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 8.2 +- 1.3 x 10^-07 erg/cm2
and the 1-sec peak flux measured from T+26.32 sec in the 15-150 keV band is
0.5 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.61 +- 0.18 (chi squared 66.38 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/623368/BA/


GRB_name: GRB150103A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17275
SUBJECT: GRB 150103A: Swift/UVOT Upper Limits
DATE:    15/01/04 04:04:17 GMT
FROM:    Lea Hagen at PSU  <lea.zernow.hagen@gmail.com>

L. M. Z. Hagen (PSU) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150103A
135 s after the BAT trigger (Hagen et al., GCN Circ. 17269). No optical
afterglow consistent with the XRT position (Osborne et al. GCN Circ.
17272) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding
chart (FC) exposures and subsequent exposures are:

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

white (fc)         135          284          147         >20.49
white              573         7047          618         >21.08
v                  624         6018          293         >19.31
b                  549         6841          471         >20.41
u (fc)             293          543          245         >19.66
u                  698         6635          451         >19.95
uvw1               673         6429          471         >19.73
uvm2               648         6224          471         >19.54
uvw2               599         7179          417         >19.67

The magnitudes in the table are not corrected for the Galactic extinction
due to the large, but uncertain, reddening of E(B-V) = 1.46 in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB150101B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17276
SUBJECT: GRB 150101B: Fermi GBM detection
DATE:    15/01/04 05:56:32 GMT
FROM:    Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>

Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team:

"At 15:23:34.47 UT on 01 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150101B (trigger 441818617 / 150101641).
which was also detected by the BAT during a slew (Cummings et al.
2015, GCN 17267).
The GBM on-ground location is consistent with the Swift/BAT position.

The angle from the Fermi LAT boresight is 44 degrees.

The GBM light curve consists of one peak
with a duration (T90) of about 0.08 s (50-300 keV).
The time-averaged spectrum from T0-0.016 s to T0+0.064 s is
best fit by a simple power law function with index -1.70 +/- 0.09.

The event fluence (10-1000 keV) in this time interval is
(1.09 +/- 0.14)E-07 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.00 s in the 8-1000 keV band
is 10.48 +/- 1.35 ph/s/cm^2.

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


GRB_name: GRB150103A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17277
SUBJECT: GRB 150103A: Swift-XRT refined Analysis
DATE:    15/01/04 10:17:24 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.C. Stroh (PSU), D.N. Burrows (PSU), J.A. Kennea (PSU), A.P. Beardmore
(U. Leicester), P.A. Evans (U. Leicester), B.P. Gompertz (U.
Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), M. de Pasquale
(INAF-IASFPA) and L.M.Z. Hagen report on behalf of the Swift-XRT team:

We have analysed 7.8 ks of XRT data for GRB 150103A (Hagen  et al. GCN
Circ. 17269),  from 116 s to 22.0 ks after the BAT trigger. The data
comprise 231 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. 17270).

The light curve can be modelled with an initial power-law decay with an
index of alpha=0.65 (+0.27, -1.19), followed by a break at T+416 s to
an alpha of 2.56 (+0.47, -0.27).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.15 (+0.16, -0.15). The
best-fitting absorption column is  1.53 (+0.30, -0.27) x 10^22 cm^-2,
in excess of the Galactic value of 9.0 x 10^21 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.8 (+0.4, -0.3) and
a best-fitting absorption column of 1.9 (+0.6, -0.5) x 10^22 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 6.5 x 10^-11 (1.2 x 10^-10) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.9 (+0.6, -0.5) x 10^22 cm^-2
Galactic foreground: 9.0 x 10^21 cm^-2
Excess significance: 3.3 sigma
Photon index:      1.8 (+0.4, -0.3)

If the light curve continues to decay with a power-law decay index of
2.56, the count rate at T+24 hours will be 3.0 x 10^-6 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.9 x
10^-16 (3.6 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/00623368.

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


GRB_name: GRB150101B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17278
SUBJECT: GRB 150101B: potential host galaxy redshift by GTC
DATE:    15/01/04 12:07:07 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

A. J. Castro-Tirado (IAA-CSIC, ISA-UMA), R. Sanchez-Ramirez, J.
Gorosabel (IAA-CSIC, UPV/EHU) and R. Scarpa (GTC), on behalf of a
larger collaboration, report:

Following the detection of the short-duration GRB 150101B by Swift/BAT
(Cummings et al. 2015, GCNC 17267) and Fermi (Stanbro et al. GCNC 17276),
we have obtained an optical spectrum with the 10.4 m GTC (+OSIRIS)
starting on Jan 4, 5:41 UT (i.e. 38.1 hr postburst), covering the
3700-10000 A wavelength range, under poor weather conditions (passing
clouds) and bad (>2.5â€) seeing. The slit included the position of the
proposed optical afterglow (Fong et al. GCNC 17271) as well as the
putative host galaxy also detected by Swift/UVOT (Cummings et al. GCNC
17258). We detect a faint emission line consistent with [OII] at z =
0.093, which we propose to be that of the potential host galaxy. If the
association is confirmed, this would make of GRB 150101B the nearest
short-duration GRB found to date. Observations at all wavelengths are
encouraged.


GRB_name: GRB150103A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17279
SUBJECT: GRB 150103A: MASTER optical observations
DATE:    15/01/04 13:53:58 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

D.Buckley, S. Potter, A. Kniazev, M. Kotze
South African Astronomical Observatory

E. Gorbovskoy,V. Lipunov, N.Tyurina, P.Balanutsa, D.Denisenko, M.Pruzhinskaya, 
A.Kuznetsov, V.Kornilov, D.Kuvshinov,
Lomonosov Moscow State University, Sternberg Astronomical Institute

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina

MASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in South Africa (Sutherland) was pointed to the  GRB150103A 33 
sec after notice time and 115 sec after trigger time at
2015-01-03 20:04:14 UT. On our first 
(20s exposure)  set we haven't found optical transient  within SWIFT 
error-box (Hagen et al., GCN Circ 17269; Evans, GCN Circ 17270; Cummings 
et al., GCN Circ 17274; Stroh et al., GCN Circ 17277).

The 5-sigma upper limit has been about 17.0mag

This limit slightly yearly than Zadko (Klotz et al., GCN CIRC 17273) and 
Swift UVOT (Hagen, GCN CIRC 17275), but not contradict to them.

This message may be cited.


GRB_name: GRB150105A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17282
SUBJECT: GRB 150105A: Fermi GBM detection
DATE:    15/01/05 15:57:11 GMT
FROM:    Oliver Roberts at UCD/Fermi  <oliver.roberts@ucd.ie>

O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:

"At 06:10:00.46 UT on the 5th of January 2014, the Fermi
Gamma-Ray Burst Monitor triggered and located GRB 150105A
(trigger 442131003 / 150105257). The GBM on-ground location,
using the Fermi GBM trigger data, is RA = 124.3, Dec =-14.8,
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 about 86 degrees.

The GBM light curve consists of several bright peaks with
a duration (T90) of about 74 s (50-300 keV). The time-
averaged spectrum from T0+3.0 s to T0+76.7 s is well fit by
a Band function with Epeak = 52 +/- 2 keV,
Alpha = -0.91 +/- 0.07 and Beta = -2.25 +/- 0.03.

The event fluence (10-1000 keV) in this time interval is
(4.4 +/- 0.1)E-05  erg/cm^2. The 1-sec peak photon flux
measured starting from T0+44.6 s in the 10-1000 keV
band is 23.5 +/- 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: GRB141121A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17284
SUBJECT: Radio upper limit on the GRB 141121A with the GMRT
DATE:    15/01/06 14:20:02 GMT
FROM:    Nayana A J at NCRA-TIFR  <nayan89deva@gmail.com>

A. J. Nayana (NCRA-TIFR)  and Poonam Chandra (NCRA-TIFR) report:

We carried out the Giant Metrewave Radio Telescope (GMRT) observations of
GRB 141121A (GCN Circ 17075) in the 1390 MHz band on 2014 December 22h56m06s UT. We do
not detect radio afterglow of the GRB in this frequency. The 3-sigma upper limit at the
GRB position (GCN Circ. 17078) is 118 uJy.

We thank GMRT staff for making these observations possible.


GRB_name: GRB150101B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17285
SUBJECT: GRB 150101B / Swift J123205.1-105602: X-ray counterpart is likely an AGN
DATE:    15/01/06 18:57:28 GMT
FROM:    Wen-fai Fong at U of Arizona  <wfong@email.arizona.edu>

W. Fong (U. Arizona), E. Berger (Harvard) and B. J. Shappee (Carnegie)
report:

"We re-observed the location of the short soft GRB 150101B (Cummings; GCN
17267) with Magellan/IMACS starting on 2015 Jan 04.30 UT (2.66 days
post-burst and 24.0 hr after our initial observations; Fong et al., GCN
17271). We obtained 10x120-sec of r-band observations in 0.82" seeing at an
airmass of 1.5.  Digital image subtraction with our first set of
observations using the ISIS package reveals no variable sources within or
near the location of the XRT source (
http://www.swift.ac.uk/xrt_positions/00020464/).  This indicates that the
unresolved optical source identified by Fong et al., (GCN 17271) is
unrelated to the GRB.

Using the redshift of z=0.134 (Levan et al. GCN 17281) for the galaxy 2MASX
J12320498-1056010 which coincides with the XRT position, we find that the
XRT source has an X-ray luminosity of LX ~ 3e43 erg/s, and remains steady
from 1.7 to 4.0 days post-burst (http://www.swift.ac.uk/xrt_curves/00020464/).
The galaxy also coincides with a bright radio source in the NRAO VLA Sky
Survey (Condon et al., 1998, AJ, 115, 1693), with a luminosity at 1.4 GHz
of nuLnu ~ 6e39 erg/s.  If due to star formation, this requires SFR ~ 150
solar masses per year, which contradicts the lack of emission lines from
the galaxy (Levan et al. GCN 17281). On the other hand, the radio and X-ray
luminosities match the properties of low-luminosity AGN with Lbol/LEdd <
10^-3 (e.g., Ho 2008, ARA&A, 46, 475).  This interpretation is also
supported by the large NIR luminosity and very red UV-NIR color (from GALEX
and 2MASS).  We therefore conclude that 2MASX J12320498-1056010 is a
low-luminosity AGN, and that the XRT source is unrelated to GRB 150101B."


GRB_name: GRB150101B
Detection_method: VLA Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17288
SUBJECT: GRB 150101B / Swift J123205.1-105602: 9.8 GHz VLA observations
DATE:    15/01/09 16:06:35 GMT
FROM:    Wen-fai Fong at U of Arizona  <wfong@email.arizona.edu>

W. Fong (U. Arizona) reports on behalf of a larger collaboration:

"We observed the field of the short/soft GRB 150101B (Cummings; GCN
17267) with the Karl G. Jansky Very Large Array (VLA) beginning on
2015 Jan 07.378 UT (5.73 days post-burst) at a mean frequency of 9.8
GHz. These observations are contemporaneous with the WSRT observations
at 4.9 GHz (van der Horst et al.; GCN 17286) and cover the
BAT position (90% containment). In 1 hour of observations, we detect
two sources within the BAT position also identified by WSRT.

The first source coincides with the galaxy 2MASX J12320498-1056010,
the XRT position (Cummings et al.; GCN 17268) and the bright source at
4.9 GHz (van der Horst et al.; GCN 17286). The 9.8 GHz flux density is
3.15 +/- 0.02 milliJy which translates to nuLnu ~ 1.5e40 erg/s (at
z=0.134; Levan et al.; GCN 17281), consistent with the interpretation
that this source is an AGN (Fong et al.; GCN 17285).

The second, fainter source is located at:

RA(J2000) = 12:32:08.19
Dec(J2000) = -10:56:14.2

with an uncertainty of 1" in each coordinate, and coincides with the
WSRT position (van der Horst et al.; GCN 17286). This
source has a 9.8 GHz flux density of 0.45 +/- 0.01 milliJy. Assuming a
single power law between 4.9 and 9.8 GHz, we calculate a spectral
index of -1.13 +/- 0.25 for this source. We note that there is no
optical source at this position in our Magellan r-band observations
(Fong et al.; GCN 17285) or in deeper r-band imaging we
obtained with Gemini-South/GMOS (17x90-sec) at 5.67 days post-burst.

We do not detect any other radio sources within the BAT position to a
3-sigma limit of 27 microJy.

We thank the VLA staff for quickly executing these observations."


GRB_name: GRB150110A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17290
SUBJECT: GRB 150110A: MAXI/GSC detection
DATE:    15/01/10 16:05:28 GMT
FROM:    H. Negoro at Nihon U.  <negoro@phys.cst.nihon-u.ac.jp>

H. Negoro (Nihon U.), S. Nakahira,  S. Ueno, H. Tomida, M. Kimura, 
M. Ishikawa, Y. E. Nakagawa (JAXA), T. Mihara, M. Sugizaki, M. Serino, 
M. Morii, J. Sugimoto, T. Takagi, A. Yoshikawa, M. Matsuoka (RIKEN), 
N. Kawai, Y. Tachibana, T. Yoshii (Tokyo Tech), A. Yoshida, T. Sakamoto, 
Y. Kawakubo, H. Ohtsuki (AGU), H. Tsunemi, D. Uchida (Osaka U.), 
M. Nakajima, K. Fukushima, T. Onodera, K. Suzuki, M. Fujita, F. Honda, 
T. Namba (Nihon U.), Y. Ueda, M. Shidatsu, T. Kawamuro, T. Hori (Kyoto U.), 
Y. Tsuboi, A. Kawagoe (Chuo U.), M. Yamauchi, Y. Morooka, D. Itoh (Miyazaki U.),
 K. Yamaoka (Nagoya U.) report on behalf of the MAXI team:

The MAXI/GSC detected a bright uncatalogued hard X-ray transient source 
around UT 2015-01-10T10:23.37.

Unfortunately, after MAXI detected the burst for about 10 sec, no data were 
obtained (or downloaded yet) for 27 seconds. 
As a result, we can not determine the X-ray flux and the source position 
correctly. 
Using the data, we obtain a rectangular error box for the transient source 
with the following corners:

(R.A., Dec) = (215.959 deg, 18.705 deg) = (14 23 50, +18 42 18) (J2000)
(R.A., Dec) = (215.630 deg, 19.420 deg) = (14 22 31, +19 25 10) (J2000)
(R.A., Dec) = (218.120 deg, 20.331 deg) = (14 32 28, +20 19 52) (J2000)
(R.A., Dec) = (218.422 deg, 19.605 deg) = (14 33 41, +19 36 18) (J2000)

There is an additional systematic uncertainty of 0.1 deg (90% containment radius).

The 4-10 keV flux is roughly about 200 mCrab.
We also note that Fermi-GBM also detected this burst almost simultaneously.

There was no significant excess flux in the previous transit at UT 08:50,
and in the next transit at UT 11:56 with an upper limit of 20 mCrab for each.

Detection Information:
http://maxi.riken.jp/alert/novae/7032899999/7032899999.htm


GRB_name: GRB150110B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17291
SUBJECT: GRB 150110B: Swift detection of a burst
DATE:    15/01/10 22:32:50 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

P. A. Evans (U Leicester), S. D. Barthelmy (GSFC),
D. N. Burrows (PSU), N. Gehrels (NASA/GSFC),
C. J. Mountford (U Leicester) and K. L. Page (U Leicester) report on
behalf of the Swift Team:

At 22:08:30 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150110B (trigger=624606).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 289.360, +32.522, which is 
   RA(J2000)  =  19h 17m 26s
   Dec(J2000) = +32d 31' 20"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows multiple peaks
structure with a duration of about 12 sec.  The peak count rate
was ~2500 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 22:09:31.0 UT, 61.0 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 289.3749,
32.5233 which is equivalent to:
   RA(J2000)  = 19h 17m 29.97s
   Dec(J2000) = +32d 31' 24.0"
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This
location is 45 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 (2.39 x
10^21 cm^-2, Willingale et al. 2013), with an excess column of 3
(+3.51/-2.95) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 65 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
0.20. 

Burst Advocate for this burst is P. A. Evans (pae9 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB150110A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17292
SUBJECT: GRB 150110A: Fermi GBM Detection
DATE:    15/01/10 23:10:54 GMT
FROM:    Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>

Matthew Stanbro (UAH) and H.-F. Yu (MPE)
report on behalf of the Fermi GBM Team:

"At 10:23:38.23 UT on 10 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150110A (trigger 442578221 / 150110433).
which was also detected by the MAXI/GSC (Negoro et al. 2015, GCN 17290)
The GBM on-ground location is consistent with the MAXI/GSC position.

The angle from the Fermi LAT boresight is 51 degrees.

The GBM light curve consists of 2 peaks
with a combined duration (T90) of about 74 s (50-300 keV).
The time-averaged spectrum from T0-2.05 s to T0+73.73 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.99 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 77.2 +/- 2.7 keV

The event fluence (10-1000 keV) in this time interval is
(2.81 +/- 0.06)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+61.1 s in the 8-1000 keV band
is 7.49 +/- .286 ph/s/cm^2.

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


GRB_name: GRB150110C
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17293
SUBJECT: GRB 150110C: MAXI/GSC detection
DATE:    15/01/11 01:59:19 GMT
FROM:    H. Negoro at Nihon U.  <negoro@phys.cst.nihon-u.ac.jp>

GRB 150110C: MAXI/GSC detection

S. Nakahira (JAXA), H. Negoro (Nihon U.),  S. Ueno, H. Tomida, 
M. Kimura, M. Ishikawa, Y. E. Nakagawa (JAXA), 
T. Mihara, M. Sugizaki, M. Serino, M. Morii, J. Sugimoto, T. Takagi, A. Yoshikawa, 
M. Matsuoka (RIKEN), N. Kawai, Y. Tachibana, T. Yoshii (Tokyo Tech), 
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU), 
H. Tsunemi, D. Uchida (Osaka U.), M. Nakajima, K. Fukushima, T. Onodera, 
K. Suzuki, M. Fujita, F. Honda, T. Namba (Nihon U.), Y. Ueda, M. Shidatsu, T. Kawamuro, 
T. Hori (Kyoto U.), Y. Tsuboi, A. Kawagoe (Chuo U.), 
M. Yamauchi, Y. Morooka, D. Itoh (Miyazaki U.), K. Yamaoka (Nagoya U.)
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered a bright uncatalogued hard X-ray 
transient source at UT2015-01-10T23:41:01.

Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (68.576 deg, -16.869 deg) = (04 34 18, -16 52 08) (J2000) 
with a statistical 90% C.L. elliptical error region 
with long and short radii of 0.19 deg and 0.17 deg respectively. 
The roll angle of long axis from the north direction is 165.0 deg 
counterclockwise. There is an additional systematic uncertainty of 0.1 deg 
(90% containment radius).
The X-ray flux averaged over the scan was 281 +- 32 mCrab (4-10keV, 1 sigma 
error).
There was no significant excess flux in the previous transit at UT 22:08 
with an upper limit of 20 mCrab.


GRB_name: GRB150110B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17294
SUBJECT: GRB 150110B: Enhanced Swift-XRT position
DATE:    15/01/11 05:52:37 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 3739 s of XRT Photon Counting mode data and 6 UVOT
images for GRB 150110B, 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 = 289.37494, +32.52333 which is equivalent
to:

RA (J2000): 19h 17m 29.99s
Dec (J2000): +32d 31' 24.0"

with an uncertainty of 1.6 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: GRB150110B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17295
SUBJECT: GRB 150110B: Fermi GBM Detection
DATE:    15/01/11 06:03:26 GMT
FROM:    Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>

Matthew Stanbro (UAH) report on behalf of the Fermi GBM Team:

"At 22:08:31.91 UT on 10 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150110B (trigger 442620514 / 150110923)
which was also detected by the Swift/BAT (Evans et al. 2015, GCN 17291)
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 22 degrees.

The GBM light curve consists of 1 peak
with a duration (T90) of about 2 s (50-300 keV).
The time-averaged spectrum from T0-1.54 s to T0+1.54 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.98 +/- 0.22 and
the cutoff energy, parameterized as Epeak, is 122.5 +/- 24.3 keV

The event fluence (10-1000 keV) in this time interval is
(5.30 +/- 0.61)E-07 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.06 s in the 8-1000 keV band
is 2.33 +/- 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: GRB150110B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17296
SUBJECT: GRB 150110B: Swift/UVOT Upper Limits
DATE:    15/01/11 06:47:06 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and P. A. Evans (U Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150110B
65 s after the BAT trigger (Evans et al., GCN Circ. 17291).  No optical
afterglow consistent with the XRT position  (Beardmore et al., GCN
Circ. 17294)  is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC            65          215          147         >21.0
u_FC               277          527          246         >20.3
white               65        12665         1414         >21.7
v                  607         6471          452         >19.6
b                  532        11960         1140         >21.5
u                  277        11047         1394         >21.1
w1                 656         6881          452         >20.4
m2                 631         6676          452         >20.5
w2                 582         6267          452         >20.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.20 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150110B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17297
SUBJECT: GRB 150110B: Swift-XRT refined Analysis
DATE:    15/01/11 10:32:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

D.N. Burrows (PSU), J.A. Kennea (PSU), B.P. Gompertz (U. Leicester),
J.P. Osborne (U. Leicester), V. D'Elia (ASDC), M. de Pasquale
(INAF-IASFPA), A. Maselli  (INAF-IASFPA), V. Mangano (PSU) and P.A.
Evans report on behalf of the Swift-XRT team:

We have analysed 8.9 ks of XRT data for GRB 150110B (Evans  et al. GCN
Circ. 17291),  from 73 s to 29.9 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Beardmore et al. (GCN Circ. 17294).

The light curve can be modelled with  a power-law decay with a decay
index of alpha=1.01 (+/-0.07).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.06 (+0.28, -0.26). The
best-fitting absorption column is  6.0 (+1.9, -1.7) x 10^21 cm^-2, in
excess of the Galactic value of 2.4 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.1 x 10^-11 (7.1 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      6.0 (+1.9, -1.7) x 10^21 cm^-2
Galactic foreground: 2.4 x 10^21 cm^-2
Excess significance: 3.6 sigma
Photon index:      2.06 (+0.28, -0.26)

If the light curve continues to decay with a power-law decay index of
1.01, the count rate at T+24 hours will be 1.9 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.8 x
10^-14 (1.4 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/00624606.

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


GRB_name: GRB150110C
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17298
SUBJECT: GRB 150110C Tiled Swift observations
DATE:    15/01/11 14:34:11 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
MAXI GRB 150110C. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00037

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the MAXI event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; and 2009, MNRAS, 397, 1177).

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


GRB_name: GRB150110A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17299
SUBJECT: GRB 150110A: MASTER inspection 
DATE:    15/01/11 15:58:55 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

E. Gorbovskoy, V. Lipunov,  P.Balanutsa, D.Denisenko,
M.Pruzhinskaya,A.Kuznetsov, V.Kornilov, D.Kuvshinov, N.Tyurina
Lomonosov Moscow State University,
Sternberg Astronomical Institute

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University


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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

D.Buckley, S. Potter, A. Kniazev
South African Astronomical Observatory

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina


MASTER-Kislovodsk robotic telescope (2x4 square degrees)  was pointed to 
MAXI-Fermi GRB150110A  (Negoro et al., GCN 17290; M. Stanbro & H.-F. Yu, GCN 17292) 
error box 4527 sec  after trigger at 22:57:30.179 UT.

There are no any optical transients inside 
error box (Negoro et al., GCN 17290;).

Our upper limit on Kislovodsk and SAAO observatiories available in Table 1.

    T_start    T0-T_start   T0-T_mid       Exptime    Mlimit
                                           (coadd)
   22:57:30.2   45247sec    47291  sec       3600      20.2

This message may be cited.


GRB_name: GRB150110B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17300
SUBJECT: GRB 150110B: Swift-BAT refined analysis
DATE:    15/01/11 16:16:12 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), P. A. Evans (U Leicester), N. Gehrels (GSFC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(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 150110B (trigger #624606)
(Evans, et al., GCN Circ. 17291).  The BAT ground-calculated position is
RA, Dec = 289.374, 32.529 deg, which is 
   RA(J2000)  =  19h 17m 29.7s 
   Dec(J2000) = +32d 31' 43.2" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 96%.
 
The mask-weighted light curve shows two peaks starting at ~T-8 sec,
peaking at ~T-5 and ~T+2 sec, and ending at ~T+10 sec.
T90 (15-350 keV) is 10.6 +- 0.95 sec (estimated error including systematics).
 
The time-averaged spectrum from T-7.94 to T+3.77 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.89 +- 0.13.  The fluence in the 15-150 keV band is 4.9 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+2.00 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/624606/BA/


GRB_name: GRB150110C
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17301
SUBJECT: GRB 150110C: Swift-XRT observations
DATE:    15/01/11 20:01:39 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

K.L. Page (U. Leicester) reports on behalf of the Swift-XRT team:

Swift-XRT has observed the error circle of the MAXI GRB 150110C in a
series of observations tiled on the sky. The total exposure time is
3.8 ks spread over 4 fields; the maximum exposure within the sky observed
was 2.4 ks. The observations started 54.2 ks after the MAXI trigger.
Within these data we detect an uncatalogued X-ray source at RA, Dec =
68.48007, -16.96802 which is equivalent to:
  RA (J2000) = 04h 33m 55.22s
  Dec (J2000) = -16d 58' 04.9"
with an uncertainty of 7.0 arcsec (radius, 90% confidence). The source has
a mean X-ray (0.3-10 keV) count rate of 4.0 (+/- 2.2) x 10^-3 count s^-1.
The exposure at this location was 1.5 ks. At the present time we cannot be
sure whether or not this source is the afterglow.

The results of the automatic processing for this source are available
at http://www.swift.ac.uk/xrt_products/TILED_GRB00037/index_1.php
This circular is an official product of the Swift-XRT team.


GRB_name: GRB150110C
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17302
SUBJECT: GRB 150110C: Swift/UVOT Upper Limits
DATE:    15/01/11 21:11:33 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

Paul Kuin (MSSL/UCL) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of MAXI GRB 150110C
54ks after the trigger.  No optical afterglow consistent with the XRT
position
(Page, GCN Circ. No. 17301)  is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures
are:

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

u                54238        59786         1896         >20.9

The magnitudes in the table 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: GRB150110B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17305
SUBJECT: GRB 150110B: Khureltogot optical upper limit
DATE:    15/01/17 19:51:52 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), S. Schmalz (AIP), N. Tungalag (Research Center of 
Astronomy and Geophysics MAS),  A. Volnova (IKI), I.Molotov (KIAM), A. 
Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of GRB GRB 150110B (Evans et al., GCN 17291) with 
ORI-40 telescope of Khureltogot observatory. We obtained several 
unfiltered images on Jan. 10 starting on (UT) 22:31:36.  In a combined 
image of the first 40 frames we  do not detect any optical source within 
  enhanced Swift-XRT position (Beardmore et al., GCN 17294). A 
photometry of the combined image is following

Date        UT start  t-T0       Filter  Exp.   ULimit (3sigma)
                       (mid, days)        (s)

2015-01-10  22:31:36  0.03113    none    40*60  19.3


The photometry is based on USNO-B1.0 stars

USNO-B1_id       RA             DEC        R2
1224-0426323     289.294781   +32.470745   13.52
1225-0423392     289.295778   +32.569009   13.80


GRB_name: GRB150118B
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17307
SUBJECT: GRB 150118B: Fermi-LAT detection
DATE:    15/01/18 23:05:42 GMT
FROM:    Daniel Kocevski at GSFC  <daniel.kocevski@nasa.gov>

D. Kocevski (NASA/GSFC), J. Racusin (NASA/GSFC), S. Zhu (UMD) and M. Arimoto (Tokyo Tech) report on behalf of the Fermi-LAT team:

At 09:48:17 UT on Jan 18th, 2015, Fermi-LAT detected high-energy emission from GRB 150118B, which was also detected by Fermi-GBM (trigger 443267300/150118409).

The best LAT on-ground location is found to be

RA, Dec = 240.24, -35.75 (J2000)

with an error radius of 0.5 deg (90% containment, statistical error only). This was ~60 deg from the LAT boresight at the time of the trigger and triggered an autonomous repoint of the spacecraft, although the source was occulted by the Earth within 150s of the GBM trigger and didn't re-enter the LAT field of view until T0+2500s

The data from the Fermi-LAT show an increase in the event rate after the GBM trigger that is temporally correlated with the GBM emission.  The detection above 100 MeV is primarily driven by a single 2 GeV event which is observed within 5 degrees of the GBM position and ~50 seconds after the GBM trigger. Using the LAT Low Energy (LLE) data selection, which is sensitive to > 30 MeV, an increase in the event rate at > 8 sigma significance above background was observed approximately coincident with the time of the GBM emission.

The Fermi-LAT point of contact for this burst is

Makoto Arimoto (arimoto@hp.phys.titech.ac.jp<mailto:arimoto@hp.phys.titech.ac.jp>).

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


GRB_name: GRB150118B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17308
SUBJECT: GRB 150118B: Fermi GBM Detection
DATE:    15/01/18 23:44:36 GMT
FROM:    Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>

Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team:

"At 09:48:17.77 UT on 18 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150118B (trigger 443267300 / 150118409)
which was also detected by the Fermi-LAT (Kocevski et al. 2015, GCN 17307)
The GBM on-ground location is consistent with the LAT position.
The trigger caused GBM to generate an Autonomous Repoint of Fermi.

The GBM light curve consists of several episodes
with a duration (T90) of about 40 s (50-300 keV).
The time-averaged spectrum from T0-4.608 s to T0+49.665 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.89 +/- 0.01 and
the cutoff energy, parameterized as Epeak, is 755 +/- 14 keV

The event fluence (10-1000 keV) in this time interval is
(1.5 +/- 0.007)E-04 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+45.8 s in the 8-1000 keV band
is 40.7 +/- 0.4 ph/s/cm^2.

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


GRB_name: GRB150120A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17310
SUBJECT: GRB 150120A: Swift detection of a possibly-short burst
DATE:    15/01/20 03:12:39 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

V. D'Elia (ASDC), D. N. Burrows (PSU), M. M. Chester (PSU),
N. Gehrels (NASA/GSFC), L. Izzo (URoma/ICRA),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
B. Sbarufatti (INAF-OAB/PSU) and M. H. Siegel (PSU) report on behalf
of the Swift Team:

At 02:57:46 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150120A (trigger=627137).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 10.308, +33.981 which is 
   RA(J2000) = 00h 41m 14s
   Dec(J2000) = +33d 58' 52"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single symmetric
peak structure with a duration of about 1.5 sec.  The peak count rate
was ~4000 counts/sec (15-350 keV), at ~0.5 sec after the trigger. 

The XRT began observing the field at 02:59:02.6 UT, 76.2 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 10.31883, 33.99480 which is equivalent
to:
   RA(J2000)  = 00h 41m 16.52s
   Dec(J2000) = +33d 59' 41.3"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 59 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 in excess of the Galactic value (7.86 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 6
(+5.52/-4.12) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 82 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 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 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: GRB150120A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17311
SUBJECT: GRB 150120A: Prompt enhanced Swift-XRT position
DATE:    15/01/20 03:24:31 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Using  promptly downlinked XRT event data for GRB 150120A, we find an
enhanced XRT position of the afterglow: RA, Dec: 10.3187, 33.9944 which
is equivalent to:
   RA (J2000)  = 00 41 16.49
   Dec (J2000) = +33 59 39.7
with an uncertainty of 2.2 arcseconds (radius, 90% confidence).
Analysis of the promptly available data is online at
http://www.swift.ac.uk/sper/627137.

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: GRB150120A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17312
SUBJECT: GRB 150120A: P60 optical observations
DATE:    15/01/20 04:06:55 GMT
FROM:    Daniel Perley at Caltech  <dperley@astro.caltech.edu>

D. A. Perley (Caltech) and S. B. Cenko (NASA/GSFC) report:

The Palomar 60-inch robotic telescope began automatic follow-up of the 
location of possibly-short GRB 150120A (D'Elia et al. GCN 17310) 
starting at 2015-01-20 03:00:33 UT, approximately 2.7 minutes after the 
GRB trigger.  A sequence of rotating r, i, and z 60-second exposures was 
acquired, followed by five 180-second exposures in each of r and i 
bands, under good conditions.

No sources are clearly detected inside the enhanced XRT error circle 
(Evans et al., GCN 17311), either in either individual exposures or in 
stacks of all 60-second exposures taken in each filter (approximate UT 
center time 15 minutes post-trigger, limiting magnitudes r>22.5, i>22.4, 
z>20.9).  We detect two faint sources slightly outside the error circle 
in the stacked frames:

  Source A:  RA=00:41:16.55, dec=+33:59:42.87
  Source B:  RA=00:41:16.76, dec=+33:59:42.11

Both sources appear to be marginally detected in SDSS pre-imaging and we 
do not yet have evidence of fading behavior.  Further observations and 
analysis are ongoing.

[GCN OPS NOTE(20jan15):  Per author's request, the date in the third line
was changed from 2015-01-t0 to 2015-01-20.]


GRB_name: GRB150120A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17313
SUBJECT: GRB 150120A: Gemini-North optical imaging
DATE:    15/01/20 07:51:01 GMT
FROM:    Wen-fai Fong at U of Arizona  <wfong@email.arizona.edu>

W. Fong (U. Arizona), R. Chornock (Ohio U.) and D. Fox (PSU) report:

"We observed the location of the possibly short GRB 150120A (D'Elia et al.,
GCN 17310) with the Gemini Multi-Object Spectrograph (GMOS) mounted on the
Gemini-North 8-m telescope starting on 2015 Jan 20.206 UT (2.0 hr after the
BAT trigger). We obtained 1800-sec in each of the riz-bands in 0.5" seeing.
Within the enhanced XRT position (Evans, GCN 17311), we do not detect any
optical sources in our images. Tied to SDSS, we calculate a 3-sigma limit
of r>26.3 AB mag.

We clearly detect two sources on the outskirts of the XRT position (Sources
A and B from P60 observations; Perley et al., GCN 17312), both of which
appear extended in our images. We do not find any evidence for variability
of these sources over the duration of our observations.

We thank Gemini observers and staff Sabrina Pakzad, Katherine Roth, Joe
Burchett, and Rongmon Bordoloi for the quick scheduling and execution of
these observations."


GRB_name: GRB150120B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17314
SUBJECT: GRB 150120B: Swift detection of a burst
DATE:    15/01/20 07:51:54 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

V. D'Elia (ASDC), L. Izzo (URoma/ICRA), N. P. M. Kuin (UCL-MSSL),
A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester), D. M. Palmer (LANL)
and M. H. Siegel (PSU) report on behalf of the Swift Team:

At 07:21:55 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150120B (trigger=627170).  Swift slewed to this burst
after a short delay due the Earth limb constraint. 
The BAT on-board calculated location is 
RA, Dec 39.294, +8.079 which is 
   RA(J2000) = 02h 37m 11s
   Dec(J2000) = +08d 04' 43"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 30 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 07:29:01.2 UT, 425.7 seconds after
the BAT trigger. The position determined from promptly downlinked data
differs significantly from the on-board position, suggesting that the
XRT may have centroided on a cosmic ray; the initial XRT position
notice should be treated with caution. Using promptly downlinked data
we find an uncatalogued X-ray source with an enhanced position: RA, Dec
39.2927, 8.0781 which is equivalent to:
   RA(J2000)  = 02h 37m 10.25s
   Dec(J2000) = +08d 04' 41.2"
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This
location is 5.7 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 1.16
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 432 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 0.20. 

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: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17315
SUBJECT: GRB 150120B: P60 optical afterglow
DATE:    15/01/20 08:11:39 GMT
FROM:    Daniel Perley at Caltech  <dperley@astro.caltech.edu>

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

The Palomar 60-inch robotic telescope began automatic follow-up of the
location of GRB 150120B (D'Elia et al., GCN 17314) starting at 07:26:07 
UT on 2015-01-20.

In the first three 60-second frames (r, i, and z-bands) we detect a 
bright (r~18.7 mag), new source at the following location (J2000):

RA  =  02:37:09.770
dec = +08:04:40.37

After these three frames, the telescope received the initial XRT 
position notice and it executed a large slew to a new position, and this 
optical source was no longer in the field of view.  It returned to the 
field with the updated XRT position notice in an image starting at 
07:47:47; the GRB afterglow shows significant fading (to r~19.7 mag) in 
this observation since the first epoch, confirming it as the optical 
afterglow.

We also note that the optical position above is near, but significantly 
outside (7 arcsec west) of, the updated XRT position given in GCN 17314.

[GCN OPS NOTE(20jan15):  Per author's request, the GRB name in the 
Subject-line was changed from 140120B to 150120B.]


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17316
SUBJECT: GRB 150120B: FTN optical afterglow confirmation
DATE:    15/01/20 08:44:28 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

C. Guidorzi, S. Dichiara (U. Ferrara), C.G. Mundell (LJMU),
A. Gomboc (U. Ljubljana) on behalf of a larger collaboration report:

The 2-m Faulkes Telescope North began observing Swift GRB150120B
(D'Elia et al. GCN 17314) on Jan 20 at 07:39:45 UT
(~18 minutes after the burst trigger) with SDSS r and i filters.
We clearly detect the optical candidate reported by Perley (GCN
17315), with a magnitude of r=19.21 +- 0.07 calibrated against
nearby USNOB-1 (R1) stars.


GRB_name: GRB150120A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17317
SUBJECT: GRB 150120A: Enhanced Swift-XRT position
DATE:    15/01/20 10:39:01 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 465 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 150120A, 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 = 10.31893, +33.99485 which is equivalent
to:

RA (J2000): 00h 41m 16.54s
Dec (J2000): +33d 59' 41.5"

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: GRB150120A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17319
SUBJECT: GRB 150120A: Fermi GBM observation
DATE:    15/01/20 13:49:42 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

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

"At 02:57:47.00 UT on 20 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150120A (trigger 443415470/150120123), which was
also detected by the Swift/BAT & XRT
(D'Elia et al. 2015, GCN 17310). The GBM on-ground location is consistent
with the Swift position.

The angle from the Fermi LAT boresight is 98 degrees.

The GBM light curve shows a single pulse
with a duration (T90) of about 2 s (50-300 keV).
The time-averaged spectrum from T0-1.024 s to T0+0.512 s is
well fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.43 (+0.28/-0.24) and
the cutoff energy, parameterized as Epeak, is 130 (+150/-50) keV

The event fluence (10-1000 keV) in this time interval is
(3.4 +/- 0.8)E-07 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0-0.64 s in the 10-1000 keV band
is 3.1 +/- 0.3 ph/s/cm^2.

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


GRB_name: GRB150120B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17320
SUBJECT: GRB 150120B: Enhanced Swift-XRT position
DATE:    15/01/20 15:06:41 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 5081 s of XRT Photon Counting mode data and 8 UVOT
images for GRB 150120B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 39.29070, +8.07795 which is equivalent
to:

RA (J2000): 02h 37m 9.77s
Dec (J2000): +08d 04' 40.6"

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

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) 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: GRB150101B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17321
SUBJECT: GRB 150101B/Swift J123205.1-105602, deep VLT observations
DATE:    15/01/20 15:31:06 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick), J. Hjorth (DARK/NBI), N.R. Tanvir, K. Wiersema (U. Leicester), A.J. van der Horst (George Washington University) report on behalf of a larger collaboration:

"We obtained further deep optical observations of the field of GRB 150101B/Swift J123205.1-105602 (Cummings; GCN17267, 17268) using the VLT and FORS2, on the 19 & 20 Jan 2015. At this epoch 1200s of observations were taken in both g, R and I, in dark time with seeing between 0.6-0.8". 

Within these deep images we locate a faint counterpart to the radio source identified by van der Horst et al. (GCN 17286) and Fong et al. (GCN 17288). It appears to be a marginally extended source with R~25 (calibrated against USNO), and to be relatively blue given its non-detection in the IR. However, its persistent radio emission implies it is likely not related to the outburst.

We do not see any object at the location of the putative optical counterpart identified in Magellan imaging by Fong et al. (GCN 17271), whose location is consistent with the presence of an X-ray source with L_X ~ 1e43 ergs/s in Chandra observations (Troja et al. GCN 17289). Given our detection of the possible radio counterpart above, we conclude that these images are deeper than those reported previously by Fong et al. (GCN 17271, GCN 17288). Although the filters are slightly different, this may suggest optical fading of this source, which would strengthen its association with GRB 150101B. 

We further note that this position clearly lies on the stellar field of the galaxy 2MASX J12320498-1056010. Such luminous, non-nuclear X-ray sources are extremely rare, and while a background AGN is possible, the small impact parameter makes this unlikely within the limited BAT error circle. The luminosity is much higher than for most short-GRB afterglows at this epoch, and there is apparently little evidence for X-ray variability (although this is complicated by the presence of the nearby AGN which is a factor ~4 brighter, Troja et al. GCN 17289). Hence, while we can not yet make firm claims about the relationship of the Magellan and Chandra source to GRB 150101B/ Swift J123205.1-105602, it remains a plausible candidate. "


GRB_name: GRB150110B
Detection_method: AMI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17322
SUBJECT: GRB 150110B: AMI 15 GHz detection of possible radio counterpart
DATE:    15/01/20 17:33:34 GMT
FROM:    Gemma Anderson at U of Oxford  <gemma.anderson@astro.ox.ac.uk>

G. E. Anderson, R. P. Fender, T. D. Staley (University of Oxford),
A. J. van der Horst (George Washington University), A. Rowlinson (CASS)

We observed the position of GRB 150110B (Evans et al., GCN 17291)
at 15 GHz with the Arcminute Microkelvin Imager (AMI-LA) starting on
2015 Jan 14.466 to 14.632 UT and 2015 Jan 16.415 to Jan 16.581,
corresponding to 3.5 and 5.5 days post-burst. On these two dates we
have detected a radio source coincident with the Swift-XRT position
(Beardmore et al., GCN 17294) with a preliminary flux of 0.25 +/- 0.05 mJy
and 0.47 +/- 0.05 mJy, respectively. There are no catalogued radio sources
at this position.

An earlier observation was conducted on 2015 Jan 11.434 to 11.580 UT,
corresponding to 0.5 days post-burst, yielding a 3 sigma flux upper limit
of 0.13 mJy.

Further AMI monitoring is planned. We thank the AMI staff for scheduling these observations.


GRB_name: GRB150120A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17323
SUBJECT: GRB 150120A: Swift/UVOT Upper Limits
DATE:    15/01/20 19:56:38 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

M. M. Chester (PSU) and V. D'Elia (ASDC) report on behalf of 
the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150120A
83 s after the BAT trigger (D'Elia et al., GCN Circ. 17310).
No optical afterglow consistent with the XRT position (Evans et al. 
GCN Circ. 17317) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposures and subsequent exposures are:

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

white_FC            83          233          147         >20.6
u_FC               295          545          246         >20.1
white               83         5674          461         >21.0
v                  624         6085          432         >19.5
b                  550        10198          449         >21.0
u                  295         6700          658         >20.6
w1                 674         6495          432         >20.5
m2                 649         6290          432         >21.1
w2                 600         5880          432         >20.5

The magnitudes in the table 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: GRB150118C
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17324
SUBJECT: IPN triangulation of GRB 150118C (short/hard)
DATE:    15/01/20 19:57:10 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

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

K. Hurley on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The short-duration, hard-spectrum GRB 150118C has been observed by Fermi 
(GBM trigger  443312075), Konus-Wind, and Mars Odyssey (HEND), so far, 
at about 80073 s UT (22:14:33).

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   160.077 (10h 40m 18s) -27.555 (-27d 33' 19")
  Corners:
   160.615 (10h 42m 28s) -27.410 (-27d 24' 37")
   160.100 (10h 40m 24s) -27.656 (-27d 39' 22")
   159.542 (10h 38m 10s) -27.693 (-27d 41' 34")
   160.054 (10h 40m 13s) -27.455 (-27d 27' 16")
  ---------------------------------------------
The error box area is 366 sq. arcmin, and its maximum
dimension is 1.0 deg (the minimum one is 12 arcmin). The Sun distance 
was 119 deg.

The center of the GBM ground position is 4.0 deg from the center of the box.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB150118_T80075/IPN/

The time history and spectrum will be given in forthcoming GCN Circulars.


GRB_name: GRB150120B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17325
SUBJECT: GRB 150120B: Swift-XRT refined Analysis
DATE:    15/01/20 20:51:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.A. Kennea (PSU), B.P. Gompertz (U. Leicester), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester), M. de Pasquale (INAF-IASFPA), A.
Maselli  (INAF-IASFPA), A. Melandri (INAF-OAB), V. Mangano (PSU), M.C.
Stroh (PSU) and V. D'Elia report on behalf of the Swift-XRT team:

We have analysed 9.0 ks of XRT data for GRB 150120B (D'Elia  et al. GCN
Circ. 17314),  from 438 s to 19.9 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. 17320).

The light curve can be modelled with  a power-law decay with a decay
index of alpha=0.91 (+/-0.05).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.97 (+0.14, -0.15). The
best-fitting absorption column is  3.2 (+0.7, -0.8) x 10^21 cm^-2, in
excess of the Galactic value of 1.2 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.8 x 10^-11 (5.6 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      3.2 (+0.7, -0.8) x 10^21 cm^-2
Galactic foreground: 1.2 x 10^21 cm^-2
Excess significance: 4.5 sigma
Photon index:      1.97 (+0.14, -0.15)

If the light curve continues to decay with a power-law decay index of
0.91, the count rate at T+24 hours will be 6.7 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.6 x
10^-13 (3.8 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/00627170.

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


GRB_name: GRB150118C
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17327
SUBJECT: Konus-Wind observation of GRB 150118C
DATE:    15/01/20 22:15:51 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

The short-duration GRB 150118C
(IPN triangulation: Golenetskii et al., GCN Circ. 17324)
triggered Konus-Wind at T0=80075.206 s UT (22:14:35.206).

The burst light curve shows a single pulse with a duration ~0.1 s.
The emission is seen up to ~1 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150118_T80075/

As observed by Konus-Wind, the burst
had a fluence of 6.2(-1.2,+1.5)x10^-7 erg/cm2,
and a 16-ms peak flux, measured from T0-0.020 s,
of 1.3(-0.4,+0.5)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+0.064 s)
is best 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 = -0.91 (-0.44,+0.56)
and Ep = 286 (-94,+204) keV (chi2 = 8/13 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2
(chi2 = 8/12 dof)

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


GRB_name: GRB150118C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17328
SUBJECT: GRB 150118C: Fermi GBM Detection
DATE:    15/01/20 22:28:31 GMT
FROM:    Eric Burns at U of Alabama  <eb0016@uah.edu>

E. Burns (UAH) report on behalf of the Fermi GBM Team:

"At 22:14:32.66 UT on 18 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150118C (trigger 443312075 / 150118927).
The GBM on-ground location is consistent with the IPN location
(K. Hurley et al. 2015, GCN 17324). The angle from the Fermi LAT
boresight is 92 degrees.

The GBM light curve consists of a single pulse
with a duration (T90) of about 0.3 s (50-300 keV).
The time-averaged spectrum from T0-0.128 s to T0+0.320 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.1 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 658 +/- 143 keV.
It is equally well fit by a Band function with
Epeak = 415 +/- 117 keV, alpha = -0.9 +/- 0.1, and
beta = -2.0 +/- 0.2.

The event fluence (10-1000 keV) in this time interval is
(1.2 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.00 s in the 10-1000 keV band
is 39.6 +/- 2.0 ph/s/cm^2.

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


GRB_name: GRB150120A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17329
SUBJECT: GRB 150120A: Swift-BAT refined analysis
DATE:    15/01/20 22:50:07 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), V. D'Elia (ASDC), N. Gehrels (GSFC), J. Norris (BSU),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(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 150120A (trigger #627137)
(D'Elia, et al., GCN Circ. 17310).  The BAT ground-calculated position is
RA, Dec = 10.330, 33.980 deg which is
   RA(J2000)  =  00h 41m 19.1s
   Dec(J2000) = +33d 58' 48.6"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 71%.

The mask-weighted light curve shows a single short spike that starts at ~ T-0.4 s, peaks
at ~ T+0.4 s, and ends at ~ T+1.0 s. T90 (15-350 keV) is 1.20 +- 0.16 sec
(estimated error including systematics).

The time-averaged spectrum from T-0.40 to T+0.95 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.81 +- 0.18.  The fluence in the 15-150 keV band is 1.4 +- 0.2 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.06 sec in the 15-150 keV band
is 1.8 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The burst spectrum appears to be at the softer end of short bursts, which have an
average spectral index of 1.2 when fitting with a simple power-law model
(Sakamoto et al. 2011). However, the fast fading shown in the X-ray light curve
(http://www.swift.ac.uk/xrt_curves/00627137/) suggests that this is indeed a short burst.
The lag analysis of this burst does not show a constraining result due to
the low intensity.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/627137/BA/


GRB_name: GRB150120B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17330
SUBJECT: GRB 150120B: Swift-BAT refined analysis
DATE:    15/01/20 22:51:16 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

C. B. Markwardt (GSFC), 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), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-61 to T+242 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 150120B (trigger #627170)
(V. D'Elia, et al., GCN Circ. 17314).  The BAT ground-calculated position is
RA, Dec = 39.309, 8.064 deg which is
  RA(J2000)  =  02h 37m 14.1s
  Dec(J2000) = +08d 03' 50.3"
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 35%.

The mask-weighted light curve shows a multi-peaked structure starts at ~ T-20 s
and ends at ~ T+10 s, with the main peak at ~ T+0 s. T90 (15-350 keV)
is 24.30 +- 3.39 sec (estimated error including systematics).

The time-averaged spectrum from T-17.64 to T+9.63 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.20 +- 0.25.  The fluence in the 15-150 keV band is 5.4 +- 0.8 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.58 sec in the 15-150 keV band
is 1.2 +- 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/627170/BA/


GRB_name: GRB150120B
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17331
SUBJECT: GRB 150120B: MITSuME Okayama upper limits
DATE:    15/01/21 01:24:44 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 MITSuME and OISTER collaboration:

We observed the field of GRB 150120B (D'Elia et al., GCNC 17314)
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 2015-01-20 11:12:04 UT (~3.8 h after the burst).
We could not detect the previously reported afterglow (Perley, GCNC 17315;
Guidorzi et al., GCNC 17316) 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
-----------------------------------------------------
0.20162    12:12:15    5760.0   >19.6  >19.6  >19.1
-----------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]


GRB_name: GRB150120A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17332
SUBJECT: GRB 150120A: KAIT Optical Upper Limit
DATE:    15/01/21 01:45:57 GMT
FROM:    Weikang Zheng at UC Berkeley  <zwk@astro.berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on 
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 150120A (D'Elia et al.,
GCN 17310) starting at 02:59:24 UT, 98 s after the burst.
Observations were performed with an automatic sequence in the
clear (roughly R), V, and I filters, and the exposure time was
20 s per image. We do not detect any new source in our
images within the enhanced XRT error circle (Evans et al.,
GCN 17317). The typical limiting magnitude of our single clear
image is about 18.5 calibrated to USNO B1.0.


GRB_name: GRB150101B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17333
SUBJECT: GRB 150101B: Confirmation of a fading optical counterpart
DATE:    15/01/21 02:13:12 GMT
FROM:    Wen-fai Fong at U of Arizona  <wfong@email.arizona.edu>

W. Fong (U. Arizona), E. Berger (Harvard), D. Fox (PSU) and B.J. Shappee
(Carnegie) report:

"We re-observed the field of the short/soft GRB 150101B (Cummings, GCN
17267) with the Gemini Multi-Object Spectrograph (GMOS) mounted on the
Gemini-South 8-m telescope starting on 2015 Jan 12.326 UT, 10.7 days after
the BAT trigger and 9.0 days after our initial Magellan observations (Fong
et al., GCN 17271). We obtained a total of 1710-sec of r-band imaging in
0.58" seeing. To assess fading of the candidate optical afterglow (Fong et
al., GCN 17271), we performed digital image subtraction using the ISIS
package between the Gemini and Magellan observations. We find a residual
point source with a refined position of

RA(J2000) = 12:32:05.08
Dec(J2000) = -10:56:03.16
with an uncertainty of 0.5" in each coordinate.

This indicates that the optical source has faded between 1.7 and 10.7 days
post-burst. Thus far, this is the only evidence for a fading source within
the BAT position. Fading is also supported by the lack of optical
counterpart in other filters from late-time VLT observations (Levan et al.,
GCN 17321). We note that digital image subtraction between our two Magellan
epochs at 1.7 days and 2.7 days post-burst revealed no residuals (Fong et
al., GCN 17285), suggesting that the source had an initial period of
shallow decay.

The optical source is ~3.1" offset from the center of the galaxy 2MASX
J12320498-1056010. Given the separation and optical brightness (Cummings et
al., GCN 17268), the galaxy has a low probability of chance coincidence of
~2e-3. At the redshift of the galaxy, z=0.134 (Levan et al., GCN 17281),
the projected physical offset is ~7.4 kpc. In addition, the location of the
optical source is consistent with the position of the faint Chandra source
(SRCX #2 in Troja et al., GCN 17289).

We conclude that the fading of the optical source, spatial coincidence with
an X-ray counterpart, and proximity to a galaxy with low probability of
chance coincidence confirms the source as the optical afterglow, and 2MASX
J12320498-1056010 as the host galaxy of GRB 150101B. At z=0.134, this is
the among the lowest confirmed redshifts for a short GRB to date."


GRB_name: GRB150120A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17334
SUBJECT: GRB 150120A: Swift-XRT refined Analysis
DATE:    15/01/21 03:12:03 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Pagani (U.
Leicester), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), B.
Sbarufatti (INAF-OAB/PSU), V. Mangano (PSU), M.C. Stroh (PSU), D.N.
Burrows (PSU) and V. D'Elia report on behalf of the Swift-XRT team:

We have analysed 5.9 ks of XRT data for GRB 150120A (D'Elia  et al. GCN
Circ. 17310),  from 86 s to 16.2 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Evans et al. (GCN Circ. 17311).

The light curve can be modelled with  a power-law decay with a decay
index of alpha=~4.6.

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.0 (+/-0.5). The
best-fitting absorption column is  6.5 (+4.8, -3.3) x 10^21 cm^-2, in
excess of the Galactic value of 7.9 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.4 x 10^-11 (7.4 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      6.5 (+4.8, -3.3) x 10^21 cm^-2
Galactic foreground: 7.9 x 10^20 cm^-2
Excess significance: 2.8 sigma
Photon index:      2.0 (+/-0.5)

If the light curve continues to decay with a power-law decay index of
~4.6, the count rate at T+24 hours will be 1.2 x 10^-13 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.4 x
10^-24 (9.0 x 10^-24) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00627137.

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


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17335
SUBJECT: GRB 150120B: Additional P60 observations
DATE:    15/01/21 03:32:27 GMT
FROM:    Daniel Perley at Caltech  <dperley@astro.caltech.edu>

D. A. Perley (Caltech) and S. B. Cenko (NASA/GSFC) report:

We obtained further observations at the position of the optical 
afterglow (Perley, GCN 17315) of GRB 150120B (D'Elia et al., GCN 17314) 
with the Palomar 60-inch robotic telescope on the night of 2015-01-21 
UT.   In a combined stack of five 300-second r-band exposures we no 
longer detect any significant emission at the location of the optical 
afterglow.  We estimate a limiting magnitude of r>22.7 mag (3 sigma) at 
a mid-time of 02:32:27 UT, t=0.799 days after the GRB.  Relative to our 
previous observations, this suggests a decay power-law slope of at least 
alpha>0.75.


GRB_name: GRB150120B
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17336
SUBJECT: GRB 150120B: GROND Afterglow Detection
DATE:    15/01/21 09:14:34 GMT
FROM:    Philip Wiseman at MPE/Swift  <wiseman@mpe.mpg.de>

P Wiseman, J Graham, P Schady and J Greiner (All MPE Garching) report on
behalf of
the GROND team:

We observed the field of GRB 150120B (Swift trigger 627170; D'Elia et al.,
GCN 17314) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started at 01:25 UT on 21.01.2015, ~18hrs after the GRB
trigger. They were performed at an average seeing of 1.1" and at an
average airmass of 1.7.

We find a single point source within the 1.4" Swift-XRT error circle (Goad
et al., GCN 17320), consistent with that
reported by Perley et al. (GCN 17315), Guidorzi et al. (GCN 17316), at

RA (J2000) = 02 h 37 m 09.77 s

DEC (J2000) = +08d 04' 40.49"

with an uncertainty of 0.3" in each coordinate.

Based on 25 min of total exposures in g'r'i'z'JHK, we estimate preliminary
magnitudes and 3 sigma upper limits (all in AB system) of

g' > 24.2
r' = 23.6 +/- 0.1 mag,
i' = 22.7 +/- 0.2 mag,
z' = 22.4 +/- 0.40 mag,
J = 20.2 +/- 0.3 mag,
H = 19.9 +/- 0.5 mag, and
K = 18.7 +/- 0.4 mag.

Based on these magnitudes, the best-fit SED has a break in the g' band
suggesting a photometric redshift of 3.5 +/-0.5.

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)=0.17 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17337
SUBJECT: GRB 150120B, Optical observations
DATE:    15/01/21 12:02:24 GMT
FROM:    Shashi Bhushan Pandey at ROTSE  <shaship@umich.edu>

S. B. Pandey (ARIES Nainital India, on behalf of larger Indian GRB
collaboration)

The 1.04m Sampurnanand telescope at ARIES Nainital began observations
of the Swift-detected GRB 150120B (D'Elia et al., GCN 17314) starting at
13:34:44 UT on 2015-01-20. Several frames in R_c pass-band 300sec each
were acquired in poor sky conditions.

In the co-added image (6x300 sec), we detect the optical afterglow candidate
at R_c ~ 21.7+-0.1 mag to the location consistent with that reported by
Perley et al. (GCN 17315), Guidorzi et al. (GCN 17316). The temporal
power-law
flux decay seems to follow an index of 0.7 at the epoch of our observations
as reported by Perley & Cenko (GCN 17335). The photometry was performed in
comparison to nearby USNO- B1 stars.

This massage may be cited.


GRB_name: GRB150120B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17338
SUBJECT: GRB 150120B: Swift/UVOT Upper Limits
DATE:    15/01/21 13:36:09 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

GRB 150120B: Swift/UVOT Upper Limits

M. M. Chester (PSU) and V. D'Elia (ASDC) report on behalf 
of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150120B
432 s after the BAT trigger (D'Elia et al., GCN Circ. 17314).
No source consistent with the optical afterglow reported by Perley 
(GCN Circ. 17315) and Guidorzi et al. (GCN Circ. 17316) is detected 
in the initial UVOT exposures.  Preliminary 3-sigma upper limits 
using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. 
Proc. 1358, 373) for the first finding chart (FC) exposure and 
subsequent exposures are:

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

white_FC           432          582          147         >19.9
white              432         1014          295         >20.5
white             7279         7479          197         >20.7
v                 6254        19560         1278         >20.1
b                 7074        25878          979         >20.9
u                 6869        25353         1999         >21.0
w1                 639         2670          214         >19.6
w1                6664        24440         2164         >21.0
m2                6459        20294         1996         >21.0
w2                1885         3036          124         >19.5
w2                7484        18646         1082         >20.8

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.20 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17339
SUBJECT: GRB150120B: Xinglong TNT optical observation
DATE:    15/01/21 14:07:31 GMT
FROM:    L.P. Xin at NAOC  <xlp@bao.ac.cn>

L. P. Xin,   X. F. Wang,  J. Y. Wei,  Y. L. Qiu, J. S. Deng, 
J. Wang,  X. H. Han and C. Wu on behalf of EAFON report:
 
We began to observe GRB 150120B (D'Elia et al., GCN 17314)  
with Xinglong  0.8-m TNT telescope at 2015-01-20, 10:56:50 (UT),
about 3.58 hours after the burst.
 
In the 15*300sec coadded R-bamd image, the optical counterpart
(D. A. Perley GCN 17315; Guidorzi et al., GCN 17316;  Wiseman et al., 17336; 
Pandey GCN 17337) was detected with a brightness of  
R=21.3+/-0.2 mag at the mid-time of 4.2 hours  after the burst, 
calibrated by the nearby USNO B1.0 R2 mag.
 
The message may be cited.
 


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17340
SUBJECT: GRB 150120B: FTN early optical light curve
DATE:    15/01/21 14:51:41 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

C. Guidorzi, S. Dichiara (U. Ferrara), C.G. Mundell (LJMU),
A. Gomboc (U. Ljubljana) on behalf of a large collaboration report:

The 2-m Faulkes Telescope North observed Swift GRB150120B
(D'Elia et al. GCN 17314; Perley GCN 17315) from 18 to 100 minutes
since the burst trigger time with SDSS r and i filters.
Both light curves are fitted with a power-law with a decay index
alpha=0.8 +- 0.1. A comparison with the observations at later times
(Perley GCN 17335; Wiseman et al. GCN 17336; Pandey GCN 17337;
Xin et al. GCN 17339) suggests that a steepening of the decay
must have occurred between ~2e4 and ~6e4 s.


GRB_name: GRB150120A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17341
SUBJECT: GRB 150120A: ISON-NM early optical limit
DATE:    15/01/21 18:22:16 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

L. Elenin (KIAM),  E. Mazaeva (IKI), A. Volnova (IKI), I. Molotov 
(KIAM), A. Pozanenko (IKI) report on behalf of larger GRB  follow-up 
collaboration:

We observed the field of the Swift GRB 150120A (D'Elia et al.,
GCN 17310) with 0.4-m telescope of ISON-NM observatory in robotic mode 
starting on Jan., 20 (UT) 02:58:58, i.e. 72 seconds after burst trigger. 
We obtained 60 unfiltered images of 30 s exposure. We do not detect any 
source within enhanced XRT error circle (Evans et al., GCN 17317):

Date      UT start   t-T0         Exp.    Filter  UL (3sigma)
                      (mid.,days)    (s)
2015-01-20 02:58:58  0.00227      5*30    Clear   19.0
2015-01-20 02:58:58  0.01950     60*30    Clear   20.2


The photometry is based on nearby SDSS DR9 stars

SDSS9_id                R_Lupton
J004136.43+340051.9     15.61
J004135.94+335950.0     14.56
J004101.23+335851.1     15.84


GRB_name: GRB150118B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17342
SUBJECT: IPN Triangulation of GRB 150118B (long/intense)
DATE:    15/01/21 21:12:38 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

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

V. Connaughton, M. S. Briggs, C. Meegan, and V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team,

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

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration, bright GRB 150118B (Kocevski et al., GCN Circ. 17307) 
has been observed by Fermi (GBM trigger 443267300; Stanbro GCN Circ. 
17308), Konus-Wind, INTEGRAL (SPI-ACS), Mars-Odyssey (HEND), MESSENGER 
(GRNS), and Swift (BAT), so far, at about 35298 s UT (09:48:18). The 
burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
   ---------------------------------------------
    RA(2000), deg                 Dec(2000), deg
   ---------------------------------------------
   Center:
    242.008 (16h 08m 02s) -36.020 (-36d 01' 12")
   Corners:
    242.375 (16h 09m 30s) -34.181 (-34d 10' 51")
    241.798 (16h 07m 12s) -36.507 (-36d 30' 24")
    241.669 (16h 06m 40s) -37.699 (-37d 41' 55")
    242.219 (16h 08m 53s) -35.520 (-35d 31' 13")
   ---------------------------------------------
The error box area is 1139 sq. arcmin, and its maximum
dimension is 3.56 deg (the minimum one is 8.3 arcmin).
The Sun distance was 52 deg.

The box is long because all annuli intersect at grazing incidence due to 
conjunction of the spacecraft involved in the triangulation.

The Fermi (LAT) position (Kocevski et al., GCN Circ. 17307) is outside 
of the box at 1.5 deg from its center.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB150118_T35302/IPN/

The Konus-Wind time history and spectrum will be given in forthcoming 
GCN Circular.


GRB_name: GRB150120B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17343
SUBJECT: GRB 150120B: RATIR Optical and NIR Observations
DATE:    15/01/21 21:24:35 GMT
FROM:    Nat Butler at Az State U  <natbutler@asu.edu>

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), Jos A. de Diego (UNAM), Leonid Georgiev (UNAM), Jess
Gonzlez (UNAM), Carlos Romn-Ziga (UNAM), Neil Gehrels (GSFC), and
Harvey Moseley (GSFC) report:

We observed the field of GRB 150120B (D'Elia, et al., GCN 17314) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronmico Nacional on
Sierra San Pedro Mrtir from 2015/01 21.09 to 2015/01 21.29 UTC (18.73 to
23.64 hours after the BAT trigger), obtaining a total of 3.91 hours
exposure in the r, i, and z bands.

For a source coincident with the GROND optical transient (Wiseman et al.,
GCN 17336), in comparison with 2MASS, we obtain the following detections
and upper limit (3-sigma):

  r = 23.4 +/- 0.2
  i = 22.6 +/- 0.1
  z > 20.72

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio Astronmico Nacional in San Pedro
Mrtir.


GRB_name: GRB150118B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17344
SUBJECT: Konus-Wind observation of GRB 150118B
DATE:    15/01/22 11:30:17 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long-duration, hard-spectrum, intense GRB 150118B
(Fermi-LAT detection: Kocevski et al., GCN 17307;
Fermi-GBM detection: Stanbro, GCN 17308;
IPN triangulation: Hurley et al., GCN 17342)
triggered Konus-Wind at T0=35302.394 s UT (09:48:22.394).

The light curve shows multiple emission episodes from ~T0-8 s to ~T0+60 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150118_T35302/

As observed by Konus-Wind, the burst had a fluence
of 1.87(-0.15,+0.14)x10^-4 erg/cm2, and a 64-ms peak flux,
measured from T0+39.680 s, of 1.88(-0.18,+0.20)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+58.368 s)
is best fit in the 20 keV - 15 MeV range
by the cutoff power law with the following model parameters:
the photon index alpha = -0.98(-0.04,+0.04),
and the peak energy Ep = 695(-42,+47) keV,
chi2 = 103/97 dof.
Fitting this spectrum with the Band model yields the same
values of alpha and Ep with an upper limit on beta of -2.8

The spectrum near the peak count rate (measured from T0+35.328 to T0+41.984 s)
is best fit in the 20 keV - 15 MeV range
by the cutoff power law with the following model parameters:
the photon index alpha = -0.84(-0.08,+0.08),
and the peak energy Ep = 614(-55,+64) keV,
chi2 = 115/98 dof.

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


GRB_name: GRB150123A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17345
SUBJECT: GRB 150123A: MAXI/GSC detection
DATE:    15/01/23 16:38:25 GMT
FROM:    Motoko Suzuki at RIKEN  <motoko@crab.riken.jp>

K. Fukushima, H. Negoro (Nihon U.), M. Serino (RIKEN), S. Nakahira (JAXA),
S. Ueno, H. Tomida, M. Kimura, M. Ishikawa, Y. E. Nakagawa (JAXA),
T. Mihara, M. Sugizaki, M. Morii, J. Sugimoto, T. Takagi, A. Yoshikawa, M. Matsuoka (RIKEN),
N. Kawai, T. Yoshii, Y. Tachibana (Tokyo Tech),
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU),
H. Tsunemi, D. Uchida (Osaka U.),
M. Nakajima, T. Onodera, K. Suzuki, T. Namba, M. Fujita, F. Honda (Nihon U.),
Y. Ueda, M. Shidatsu, T. Kawamuro, T. Hori (Kyoto U.),
Y. Tsuboi, A. Kawagoe (Chuo U.),
M. Yamauchi, Y. Morooka, D. Itoh (Miyazaki U.),
K. Yamaoka (Nagoya U.)
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 15:01:50 UT .
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (111.560 deg, -9.691 deg) = (07 26 14, -09 41 27) (J2000)
with a statistical 90% C.L. elliptical error region
with long and short radii of 0.14 deg and 0.13 deg respectively.
The roll angle of long axis from the north direction is 110.0 deg counterclockwise.
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
The X-ray flux averaged over the scan was 332 +- 36 mCrab
(4-10keV, 1 sigma error).
There was no significant excess flux in the previous transit at UT 13:29
and in the next transit at 16:34 UT with an upper limit of 20 mCrab
for each.


GRB_name: GRB150123A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17346
SUBJECT: GRB 150123A Tiled Swift observations
DATE:    15/01/23 17:34:23 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
MAXI GRB 150123A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00038

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the MAXI event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; and 2009, MNRAS, 397, 1177).

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


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17347
SUBJECT: GRB 150120B: Mondy optical observations
DATE:    15/01/23 19:00:55 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), A. Volnova (IKI), E. Klunko (ISTP), I. Korobtsev 
(ISTP), M. Eselevich (ISTP), A. Pozanenko (IKI) report on behalf of 
larger GRB follow-up collaboration:

We observed the field of GRB 150120B  (D'Elia et al., GCN 17314) with 
AZT-33IK telescope of Sayan observatory (Mondy) Jan., 20  starting on 
(UT) 11:42:02. We obtained 65 images in R-filter of 120 s exposure. In 
two combined images within  enhanced Swift-XRT error circle (Goad
et al., GCN 17320) we clearly  detect optical  afterglow (Perley et al. 
GCN 17315, Guidorzi et al. GCN 17316). Photometry of the afterglow is 
following

Date       UT start   t-T0     Filter   Exp.    OT    Err.
                       (mid, days)       (s)

2015-01-20 11:42:02   0.20149  R        30*120  21.25 0.22
2015-01-20 12:42:04   0.24348  R        30*120  21.43 0.25

Photometry is based on nearby USNO B1.0 (R2) stars:

USNO-B1.0_id R
0980-0031064 15.57
0980-0031070 14.16
0980-0031080 16.35
0980-0031095 15.41


GRB_name: GRB150123A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17348
SUBJECT: GRB 150123A: Swift-XRT observations
DATE:    15/01/24 10:33:12 GMT
FROM:    Andrea Melandri at INAF-OAB  <andrea.melandri@brera.inaf.it>

A. Melandri, P. D'Avanzo, M.G. Bernardini (INAF-OAB) & P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has observed the error circle of the MAXI GRB 150123A in a series of observations tiled on the sky. The total exposure time is 3.7 ks spread over 4 fields; the maximum exposure within the sky observed was 1.6 ks. The observations started 9.8 ks after the MAXI trigger. 

Within these data there are 3 objects which are not catalogued in the X-rays.

Source details:

Source 1
RA:  111.36420 = 07h 25m 27.41s (J2000)
Dec:  -9.74880  = -09d 44' 55.7" (J2000)
Err: 5.9 (radius, 90% confidence)
Exposure time: 814 s
Online products:
http://www.swift.ac.uk/xrt_products/TILED_GRB00038/index_1.php

Source 2
RA:  111.52056 = 07h 26m 4.93s (J2000)
Dec:  -9.65269  = -09d 39' 09.7" (J2000)
Err: 4.4 (radius, 90% confidence)
Exposure time: 1.3 ks
Online products:
http://www.swift.ac.uk/xrt_products/TILED_GRB00038/index_2.php

Source 3
RA:  111.40659 = 07h 25m 37.58s (J2000)
Dec:  -9.55462  = -09d 33' 16.6" (J2000)
Err: 5.2 (radius, 90% confidence)
Exposure time: 1.5 ks
Online products:
http://www.swift.ac.uk/xrt_products/TILED_GRB00038/index_3.php


Source #1 is located 3" from an optical source present in the USNO-B1.0 catalogue with a magnitude of R=15.5. Source #2 is located 4" from an optical source present in the USNO-B1.0 catalogue with a magnitude of R=18.0. Source #3 matches the position of the known bright star TYC 5400-1552-1 (R=10.8). 

At the present time we cannot be sure which, if any, of these is the afterglow.

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


GRB_name: GRB150123A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17349
SUBJECT: GRB 150123A: Swift/UVOT observations
DATE:    15/01/24 12:49:07 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (IAA-CSIC/UCL-MSSL) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of MAXI GRB 150123A
8.7ks after the trigger. No optical afterglow is detected within the MAXI 
error circle (Fukushima, GCN Circ. No. 17345). Using the UVOT photometric 
system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) We obtain a typical 
3 sigma upper limit of >20.6 in the u filter. This magnitude has not been 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).

In the error circles for XRT candidates #1, #2, and #3 we note the presence of objects 
that are catalogued in the USNO-B1, as discussed in Melandri et al. (GCN Circ. No. 17348). 
At the present time we cannot determine if any of these objects are fading.


GRB_name: GRB150120A
Detection_method: AMI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17350
SUBJECT: GRB 150120A: possible AMI 15 GHz detection
DATE:    15/01/26 10:59:48 GMT
FROM:    Gemma Anderson at U of Oxford  <gemma.anderson@astro.ox.ac.uk>

G. E. Anderson, R. P. Fender, T. D. Staley (University of Oxford),
A. J. van der Horst (George Washington University), A. Rowlinson (CASS)

We observed the position of the possibly-short burst GRB 150120A
(DElia et al., GCN 17310) at 15 GHz with the Arcminute Microkelvin Imager
(AMI-LA) starting on 2015 Jan 21.690 to 21.856 UT, corresponding to 1.6 days
post-burst. On this date we possibly detected a ~4 sigma radio source with flux
0.17 +/- 0.04 mJy at the position
RA(J200): 0:41:16.72
Dec(J2000): 33:59:55.4
with a positional uncertainty of ~10 arcseconds. This is ~14 arcseconds from
the best XRT position quoted by Evan et al., GCN 17317.

An earlier and later observation was conducted on 2015 Jan 20.475 to 20.559 UT
and 2015 Jan 22.666 to 22.832 UT, corresponding to 0.4 and 2.5 days post-burst,
yielding 3 sigma flux upper limits of 0.19 mJy and 0.10 mJy, respectively.

Further AMI monitoring is planned. We thank the AMI staff for scheduling these observations.


GRB_name: GRB150123A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17351
SUBJECT: Konus-Wind observation of GRB 150123A
DATE:    15/01/26 18:06:25 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, 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 150123A localized by MAXI/GSC (Fukushima et al., GCN
17345) was detected by Konus-Wind in the waiting mode.

The burst light curve shows a single pulse started at ~T0(MAXI)-39 s 
with a duration of ~70 s.

As observed by Konus-Wind, the burst had a fluence of
7.42(-0.80,+0.88)x10^-6 erg/cm2 and a 2.944-s peak flux,
measured from ~T0(MAXI)-1 s, of (1.6 +/- 0.7)x10^-7 erg/cm2 (both in the 
20 - 1200 keV energy range).

Fitting the K-W 3-channel time-integrated spectrum (from T0(MAXI)-39 s 
to T0(MAXI)+31 s) by a simple power-law model yields a power law index 
of 1.82 +/- 0.1 (chi2=1.0/1 dof).

All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.

The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB150123A/


GRB_name: GRB150126A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17352
SUBJECT: GRB 150126A: MAXI/GSC afterglow candidate detection
DATE:    15/01/27 01:54:30 GMT
FROM:    Motoko Suzuki at RIKEN  <motoko@crab.riken.jp>

T. Takagi (RIKEN), S. Nakahira (JAXA), M. Serino (RIKEN), H. Negoro (Nihon U.),
S. Ueno, H. Tomida, M. Kimura, M. Ishikawa, Y. E. Nakagawa (JAXA),
T. Mihara, M. Sugizaki, M. Morii, J. Sugimoto, A. Yoshikawa, M. Matsuoka (RIKEN),
N. Kawai, T. Yoshii, Y. Tachibana (Tokyo Tech),
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU),
H. Tsunemi, D. Uchida (Osaka U.),
M. Nakajima, K. Fukushima, T. Onodera, K. Suzuki, T. Namba, M. Fujita, F. Honda (Nihon U.),
Y. Ueda, M. Shidatsu, T. Kawamuro, T. Hori (Kyoto U.),
Y. Tsuboi, A. Kawagoe (Chuo U.),
M. Yamauchi, Y. Morooka, D. Itoh (Miyazaki U.),
K. Yamaoka (Nagoya U.)
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered an uncatalogued X-ray transient 
source at 21:03:24 UT.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (350.503 deg, -12.368 deg) = (23 22 00, -12 22 04) (J2000)
with a statistical 90% C.L. elliptical error region
with long and short radii of 0.56 deg and 0.46 deg respectively.
The roll angle of long axis from the north direction is 145.0 deg 
counterclockwise.
There is an additional systematic uncertainty of 0.1 deg (90% containment 
radius).
The X-ray flux averaged over the scan was 55 +- 17 mCrab
(4-10keV, 1 sigma error).
There was no significant excess flux in the previous transit at UT 19:30
and in the next transit at 22:35 UT with an upper limit of 20 mCrab for 
each.

This position is about 2 degree from the position of the Fermi trigger 
#443998238. Considering the Fermi detection, the transit time, and the spectral
softness, the source is likely to be the afterglow of the GRB triggered
by Fermi.


GRB_name: GRB150126A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17353
SUBJECT: GRB 150126A: Fermi GBM Detection
DATE:    15/01/27 06:15:49 GMT
FROM:    Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>

Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team:

"At 20:50:35.78 UT on 26 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150126A (trigger 443998238 / 15012686)
which MAXI detected an afterglow candidate (Takagi et al. 2015, GCN 17352).
The GBM on-ground location is consistent with MAXI position.

The angle from the Fermi LAT boresight is 92 degrees.

The GBM light curve consists of 2 main episodes
with a duration (T90) of about 97 s (50-300 keV).
The time-averaged spectrum from T0-2.05 s to T0+91.14 s is
best fit by a Band function with Epeak = 217 +/- 17 keV,
alpha = -1.07 +/- 0.04, and beta = -2.45 +/- 0.22

The event fluence (10-1000 keV) in this time interval is
(2.55 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+71.3 s in the 10-1000 keV band
is 9.71 +/- 0.36 ph/s/cm^2.

A power law function with an exponential high-energy cutoff fits
the spectrum equally well. The power law index is -1.11 +/- 0.03 and
the cutoff energy, parameterized as Epeak, is 240 +/- 13 keV.

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


GRB_name: GRB150127A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17355
SUBJECT: GRB150127A: Fermi GBM Detection
DATE:    15/01/28 00:46:25 GMT
FROM:    Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>

Matthew Stanbro (UAH) and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team:

"At 09:32:44.14 UT on 27 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150127A (trigger 444043967 / 150127398).

The on-ground calculated location, using the GBM trigger
data, is RA = 285.7, DEC = -8.4, with an uncertainty
of 2.8 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 39 degrees.

The GBM light curve consists of several episodes
with a duration (T90) of about 53 s (50-300 keV).
The time-averaged spectrum from T0-0.00 s to T0+51.20 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.04 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 1478 +/- 225 keV.

A Band function fits the spectrum equally well
with Epeak= 1083 +/- 212 keV, alpha = -0.99 +/- 0.05 and beta = -2.21 +/- 0.23.

The event fluence (10-1000 keV) in this time interval is
(2.27 +/- 0.50)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.32 s in the 10-1000 keV band
is 7.78 +/- 0.33 ph/s/cm^2.

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


GRB_name: GRB150127A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17356
SUBJECT: GRB 150127A: Fermi-LAT detection
DATE:    15/01/28 02:05:36 GMT
FROM:    Judith Racusin at GSFC  <judith.racusin@nasa.gov>

J. L. Racusin (NASA/GSFC), G. Vianello (Stanford), and D. Kocevski 
(NASA/GSFC) report on behalf of the Fermi-LAT team:

At 09:32:44 on January 27, 2015, Fermi-LAT detected emission from 
GRB 150127A, which was also detected by Fermi-GBM (trigger 
444043967/150127398, GCN 17355).

The GBM location was initially inside the LAT field of view at an angle 
of ~39 degrees to the LAT boresight.  No significant excess is seen 
using standard analysis procedures >100 MeV.

Using the LAT Low Energy (LLE) data selection, over 60 counts 
above background were detected within a 10 s interval coinciding 
with the time of the GBM emission. This data selection has 
insufficient spatial resolution to provide a reliable LAT localization. 
Since an excess of events were not seen using the standard 
analysis selection, this detection is likely due to low energy 
gamma-rays (below 100 MeV).

The Fermi LAT point of contact for this burst is 
Judith Racusin (judith.racusin@nasa.gov).

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


GRB_name: GRB150126A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17357
SUBJECT: Konus-Wind observation of GRB 150126A reveals its ultra-long nature
DATE:    15/01/28 16:45:07 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

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

The GRB 150126A (MAXI/GSC detection: Takagi et al., GCN 17352; Fermi-GBM 
detection: Stanbro, GCN 17353) triggered Konus-Wind at T0=75103.524 s UT 
(20:51:43.524).

The burst light curve shows several multi-peak emission episodes started 
at ~T0-800 s with a total duration of ~870 s; the last, most intense 
pulse triggered Konus-Wind. There is a hint of low-level ongoing 
emission in the soft energy band G1 (~83-360 keV) out to about T0+230 s.
The K-W light curve and the K-W ecliptic latitude response confirm a 
common origin of all episodes. The position of the burst (Takagi et al., 
GCN 17352) was below the horizon for Fermi until ~20:50 UT (=T0(KW)-103 
s), so it missed all emission episodes except the last one.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150126_T75103/

As observed by Konus-Wind, the burst had a fluence of 
8.56(-0.88,+1.30)x10^-5 erg/cm2, and a 1024-ms peak flux, measured from 
T0+8.288 s, of 1.03(-0.23,+0.24)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The spectrum of the triggered part of the burst
(measured from T0 to T0+24.832 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.04(-0.28,+0.33)
and Ep = 208(-36,+57) keV (chi2 = 74/60 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < 2.1
(chi2 = 74/59 dof)

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

The burst duration, light curve shape, and energetics are similar to 
those of other multi-episode ultra-long GRBs with durations of ~1-2 ks 
(e.g. GRB 020410A, GRB 080407A, GRB 091024A, GRB 110709B - see Virgili 
et al. (2013), ApJ, 778:54 and references therein).

[GCN OPS NOTE(28jan15): Per author's request, the "A" was added to the GRB name
in the Subject-line.]


GRB_name: GRB150120A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17358
SUBJECT: GRB 150120A: Gemini-N imaging and host redshift
DATE:    15/01/28 22:40:07 GMT
FROM:    Ryan Chornock at Ohio U  <chornock@ohio.edu>

R. Chornock (Ohio University) and W. Fong (University of Arizona) report:

We re-imaged the field of the possibly-short GRB 150120A (D'Elia et al.,
GCN 17310) with the Gemini Multi-Object Spectrograph (GMOS) mounted on the 
Gemini-North 8-m telescope starting on 2015 Jan 22.284 UT (2.16 days
post-burst and 49.8 hr after our first Gemini observations; Fong et al.,
GCN 17313). We obtained a total of 2160s of observations in r-band in
1.0" seeing at an airmass of 1.6. Image subtraction using the ISIS package 
reveals no residuals in or around the enhanced XRT position (Evans et al.,
GCN 17317). Based on the 3-sigma limit of the second epoch, which is not
deep as our first epoch due to poorer conditions, we place a limit of r(AB)>25.0 
mag on the optical afterglow of GRB 150120A at 2.0 hr
post-burst.

We note that the enhanced XRT position (Evans et al., GCN 17317) shifted
relative to the prompt enhanced XRT position (Evans, GCN 17311) and now 
encompasses Source A of Perley & Cenko (GCN 17312), while Source B is now
just outside the XRT error circle.  We placed a spectroscopic slit across
both Sources A and B and obtained a pair of 900s GMOS spectra on 2014 Jan.
27 with the R400 grating (range 4900-9200 Angs).  Both galaxies exhibit
nebular emission lines (H-beta, [O III]) at the same common redshift of
z=0.460.

We thank the staff at Gemini for their assistance scheduling and
performing these observations.


GRB_name: GRB150127A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17359
SUBJECT: IPN Triangulation of GRB 150127A
DATE:    15/01/29 21:40:41 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

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

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration GRB 150127A has been detected by Fermi (GBM: Stanbro 
and von Kienlin, GCN Circ. 17355; LAT (but not localized): Racusin et 
al., GCN Circ. 17356), Konus-Wind, MESSENGER (GRNS), and Mars-Odyssey 
(HEND), so far, at about 34364 s UT (09:32:44).

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
---------------------------------------------
    RA(2000), deg                 Dec(2000), deg
   ---------------------------------------------
   Center:
    296.953 (19h 47m 49s)  -9.416 ( -9d 24' 58")
   Corners:
    297.190 (19h 48m 46s)  -6.883 ( -6d 52' 58")
    296.956 (19h 47m 50s)  -7.457 ( -7d 27' 25")
    296.868 (19h 47m 28s) -13.764 (-13d 45' 49")
    297.021 (19h 48m 05s) -12.130 (-12d 07' 50")
   ---------------------------------------------
The error box area is 1.1 sq. deg, and its maximum
dimension is 6.9 deg (the minimum one is 11 arcmin).
The Sun distance was 13 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB150127_T34360/IPN/

The Konus-Wind time history and spectrum will be given in forthcoming 
GCN Circulars.


GRB_name: GRB150127B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17360
SUBJECT: IPN Triangulation of GRB 150127B
DATE:    15/01/29 22:08:46 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

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

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team,

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

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

A long-duration GRB 150127B has been observed by Fermi (GBM trigger 
444060509), Konus-Wind, Mars-Odyssey (HEND), MESSENGER (GRNS), and Swift 
(BAT), so far, at about 50906 s UT (14:08:26). The burst was outside the 
coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
    ---------------------------------------------
    RA(2000), deg                 Dec(2000), deg
   ---------------------------------------------
   Center:
    140.184 (09h 20m 44s)  -3.205 ( -3d 12' 18")
   Corners:
    140.849 (09h 23m 24s)  -3.717 ( -3d 43' 00")
    140.139 (09h 20m 33s)  -3.925 ( -3d 55' 29")
    139.534 (09h 18m 08s)  -2.676 ( -2d 40' 32")
    140.241 (09h 20m 58s)  -2.479 ( -2d 28' 43")
   ---------------------------------------------
The error box area is 1.0 sq. deg, and its maximum
dimension is 1.7 deg (the minimum one is 43 arcmin).
The Sun distance was 155 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB150127_T50911/IPN/

The time history and spectrum will be given in forthcoming GCN Circulars.


GRB_name: GRB150120A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17361
SUBJECT: GRB 150120A: 9.8 GHz VLA upper limit
DATE:    15/01/30 00:44:17 GMT
FROM:    Wen-fai Fong at U of Arizona  <wfong@email.arizona.edu>

W. Fong (U. Arizona) reports:

"We observed the field of the possibly-short GRB 150120A (D'Elia et al.,
GCN 17310) with the Karl G. Jansky Very Large Array (VLA) beginning on 2015
Jan 21.027 UT (21.7 hr post-burst) at a mean frequency of 9.8 GHz. In 70
min of observations, we do not detect any radio source within or around the
enhanced XRT position (Evans et al., GCN 17317). In addition, we do not
detect any radio source within or near the position of the possible AMI
source at 15 GHz (Anderson et al., GCN 17350). We therefore place a 3-sigma
limit of ~30 microJy on the 9.8 GHz radio afterglow of GRB 150120A at 21.7
hr after the burst.

We thank the VLA staff for quickly executing these observations."


GRB_name: GRB150123A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17362
SUBJECT: GRB 150123A: MASTER inspection
DATE:    15/01/30 10:24:03 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

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

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University


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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina


MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Tunka, Kislovodsk and SAAO made inspection inside MAXI 
GRB150123A  (Fukushima et. al GCN 17345) error box  which starting 3297 
sec after trigger time at 2015-01-23 15:56:47 UT. We don't find creadible 
OT candidate in MAXI error box  on single and coadd images with following 
upper limits.

T_start  T-Tmid   Exp  Site Coadd Mlimit  Comment
15:56:47   3297   180 Tunka    --   15.0  High clouds
15:56:55   3305   180 Kilov    --   17.0  5 images only
16:28:50   6562  1800 Tunka    10   19.0
17:14:03   8974  1800 Tunka    10   19.0
18:44:04  13186   180 SAAO     --   18.5  Starting after sunset.
18:44:04  14398  1620 SAAO      9   20.6
19:20:41  17075  1800 SAAO     10   20.6

We also check all Swift-XRT transints (Melandri et. al. GCN 17348) on all 
out images.
Source #1 is a galaxy with no avidance for brightening.
Source #2 empty space with no OT and known stars at edge of error circle
Source #3 position is blended by close bright stars.



This message may be cited.


GRB_name: GRB150127B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17363
SUBJECT: Konus-Wind observation of GRB 150127B
DATE:    15/01/30 14:03:07 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

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

The long-duration GRB 150127B (IPN triangulation: Hurley et al., GCN 
17360) triggered Konus-Wind at T0=50911.89 s UT (14:08:31.890).

The burst light curve shows two multi-peak emission episodes with a 
total duration of ~90 s.
The emission is seen up to ~1 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150127_T50911/

As observed by Konus-Wind, the burst
had a fluence of 5.43(-0.21,+0.23)x10^-5 erg/cm2,
and a 256-ms peak flux, measured from T0+10.288 s,
of 2.97(-0.43,+0.43)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured 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:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.98(-0.10,+0.10)
and Ep = 197(-12,+14) keV (chi2 = 40/58 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.8
(chi2 = 40/57 dof)

The spectrum near the maximum count rate
(measured from T0+0.000 to T0+16.640 s)
is best 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 = -0.23(-0.13,+0.14)
and Ep = 252(-13,+14) keV (chi2 = 49/58 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.9
(chi2 = 47/57 dof)

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


GRB_name: GRB150127B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17364
SUBJECT: GRB 150127B: Fermi GBM detection
DATE:    15/01/30 17:36:16 GMT
FROM:    Peter Jenke at MSFC  <peter.a.jenke@nasa.gov>

P. Jenke (UAH) and A. von Kienlin (MPE) report
 on behalf of the Fermi GBM Team:

"At 14:08:26.68 UT on January 27 2015, the Fermi Gamma-Ray Burst 
Monitor triggered and located 
GRB 150127B (trigger 444060509/150127589). The GBM on-ground 
location, using the Fermi GBM trigger data, is consistent with
the IPN Triangulation (K. Hurley et al., GCN 17360).  This burst
was also observed by Konus-Wind (S. Golenetskii et al., GCN 17363).

The angle of the burst direction to the Fermi LAT boresight is 
80 degrees.

The GBM light curve consists of two peaks with a duration
(T90) of about 61 s (50-300 keV).
The time-averaged spectrum from T0+0.0 s to T0+79 s is
adequately fit by a Band function with Epeak = 240 +/- 7 keV,
Alpha =-1.08 +/- 0.01 and Beta = -2.8 +/- 0.2.  The spectrum is also
well fit by a power law function with an exponential 
high-energy cutoff.  The power law index is -1.09 +/- 0.01
and the cutoff energy, parameterized as Epeak, is 250 +/- 5 keV.

The event fluence (10-1000 keV) in this time interval is
(1.99 +/- 0.01)E-05 erg/cm^2. The 1 s peak photon flux measured
starting from T0+55 s in the 10-1000 keV band
is 19.8 +/- 0.4 ph/s/cm^2.

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


GRB_name: GRB150128A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17365
SUBJECT: GRB 150128A: MASTER OT detction during inspection 
DATE:    15/01/30 20:29:37 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

O.Gres, K.Ivanov,  S.Yazev, N.M.Budnev,  V.A.Poleshchuk
Irkutsk State University

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University


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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory

H. Levato and C. Saffe
Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE),
San Juan, Argentina

C. Mallamacci, C. Lopez and F. Podest
Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, 
Argentina

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Tunka was pointed to the  GRB150128A 34 sec after notice time 
and 124 sec after trigger time at 2015-01-28 19:01:18 UT. We made several 
20s alert exposures  on the centre of  first  FERMI error box (ra=18 11 00 
dec=+24 21 58 r=11.2). Than we start inspect survey inside this error box 
with average upper limit 18.9 mag.
After more exact coordinates comes MASTER II  robotic telescope located in 
Tunka was pointed on the centre of new FERMI error-box  (ra=18 09 03 
dec=+27 46 48 r=3.320000) 25 sec after notice time and 11821 sec after 
trigger time at 2015-01-28 22:16:15 UT. Than we continued  inspect survey 
inside new error box with upper limit from 18 to 19.
MASTER II  robotic telescope  located in Kislovodsk was starting inspect 
survey on the FERMI   error-box (ra=18 09 03 dec=+27 46 48 r=3.3)  15569 
sec after notice time and 27364 sec after trigger time at 2015-01-29 
02:35:18 UT with average upper limit from 17.5 to 19.

During the inspection of the error box of a long (more than 60 sec) 
multi-peak gamma-ray burst GRB 150128A (Fermi trigger 444164357, INTEGRAL 
SPI-ACS trigger 6874) MASTER-Tunka auto-detection system discovered OT 
source at

(RA, Dec) = 18h 01m 53.15s +25d 43m 23.5s

on 2015-01-28.91546 UT 
(V.Shumkov et al., Atel 7010). The OT unfiltered magnitude is 16.6m 
(limit 
18.6m). The OT is seen in 3 images. There is no minor planet at this 
place. We have reference image without OT on 2011-06-28.73624 UT with 
unfiltered magnitude limit 19.8m. For the description of Global MASTER 
Robotic Net see Lipunov et al., 2010, Advances in Astronomy, article id. 
349171, pp. 1-7. )

MASTER-net coverage map available here:

First  error-box r=11.1d 
http://master.sai.msu.ru/static/GRB150128_net2.png
Second error-box r= 3.3d 
http://master.sai.msu.ru/static/GRB150128_net.png


This message may be cited.

[GCN OPS NOTE(30jan15):  The operator removed the redundnat "GRB"
from the Subject-line and added the "A" suffix in two places
in the body of the Circular.]


GRB_name: GRB150120B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17366
SUBJECT: GRB 150120B: Khureltogot optical observations
DATE:    15/01/30 21:25:11 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), S. Schmalz (AIP), N. Tungalag (Research Center of 
Astronomy and Geophysics MAS),  A. Volnova (IKI), I.Molotov (KIAM), A. 
Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150120B  (D'Elia et al., GCN 17314) with 
ORI-40 telescope of Khureltogot observatory on Jan., 20  starting on 
(UT) 10:52:51. We obtained 90 unfiltered images of 60 s exposure. 
Within  enhanced Swift-XRT error circle (Goad et al., GCN 17320)  we 
clearly detect optical  afterglow (Perley et al. GCN 17315, Guidorzi et 
al. GCN 17316) in a combined image. Photometry of the afterglow is 
following

Date        UT start  t-T0       Filter  Exp.   OT    OT_err
                       (mid, days)        (s)

2015-01-20  10:52:51  0.18068    none    90*60  20.75 0.20

The photometry is based on R magnitudes of nearby USNO-B1.0 stars

USNO-B1_id   R2
0981-0032639 16.04
0981-0032644 17.10


GRB_name: GRB150201A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17368
SUBJECT: GRB 150201A: Swift detection of a burst
DATE:    15/02/01 14:00:16 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

J. K. Cannizzo (NASA/UMBC), A. P. Beardmore (U Leicester),
N. Gehrels (NASA/GSFC), H. A. Krimm (CRESST/GSFC/USRA),
D. Malesani (DARK/NBI), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester) and T. N. Ukwatta (LANL) report on behalf of
the Swift Team:

At 13:46:59 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150201A (trigger=629302).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 11.832, -37.625 which is 
   RA(J2000) = 00h 47m 20s
   Dec(J2000) = -37d 37' 29"
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 20 sec.  The peak count rate
was ~21500 counts/sec (15-350 keV), at ~2 sec before the trigger. 

The XRT began observing the field at 13:48:26.8 UT, 87.2 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 11.8325, -37.6193 which is equivalent to:
   RA(J2000)  = +00h 47m 19.80s
   Dec(J2000) = -37d 37' 09.5"
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This
location is 20 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 3.03e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 92 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 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 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: GRB150201A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17369
SUBJECT: GRB 150201A: Enhanced Swift-XRT position
DATE:    15/02/01 18:44:34 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 308 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 150201A, 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 = 11.83271, -37.61883 which is equivalent
to:

RA (J2000): 00h 47m 19.85s
Dec (J2000): -37d 37' 07.8"

with an uncertainty of 1.6 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: GRB150201A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17370
SUBJECT: GRB 150201A: Fermi GBM observation
DATE:    15/02/02 02:08:31 GMT
FROM:    Veronique Pelassa at UAH  <vero.pelassa@gmail.com>

H.-F. Yu (MPE) and V. Pelassa (UAH) report on behalf of the Fermi GBM Team:

"At 13:46:55.15 UT on 01 Feb 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150201A (trigger 444491218 / 150201574),
which was also detected by the Swift (Cannizzo et al. 2015, GCN 17368).
The GBM on-ground location is consistent with the Swift position.
The trigger resulted in an Autonomous Repoint Request (ARR) that was
accepted and the spacecraft slewed to the GBM in-flight location.
The angle from the Fermi LAT boresight is about 60 degrees.

The GBM light curve shows a double-peaked pulse with a duration (T90)
of about 16 s (50-300 keV). The time-averaged spectrum from T0-2.816 s
to T0+36.097 s is well fit by a Band function with Epeak = 131 +/- 2 keV,
alpha = -1.02 +/- 0.01, and beta = -2.70 +/- 0.06. The event fluence
(10-1000 keV) in this time interval is (6.63 +/- 0.05)E-05 erg/cm^2.
The 1.024-sec peak photon flux measured starting from T0+4.608 s in
the 10-1000 keV band is 88.7 +/- 0.7 ph/s/cm^2.

GBM triggered on GRB 150201590 23 minutes after GRB 150201A,
at 14:09:56 UT (MET 444492598). The GBM localization of this 2nd trigger
is RA, Dec = 2.1, -40.7 with an uncertainty of 2.7 deg (radius, 1-sigma
containment,statistical only; there is additionally a systematic error
which is currently estimated to be 2 to 3 degrees).  This is consistent
with the position of GRB 150201A.

As seen by GBM, this second event shows a multi-peaked pulse with a
duration (T90) of about 26 s (50-300 keV). The time-averaged spectrum
from T0-0.512 s to T0+22.016 s is well fit by a power law function with
an exponential high-energy cutoff. The power law index is -0.61 +/- 0.15
and the cutoff energy, parameterized as Epeak, is 105 +/- 8 keV. The
event fluence (10-1000 keV) in this time interval is
(2.13 +/- 0.11)E-06 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0+7.104 s in the 10-1000 keV band is 2.1 +/- 0.2 ph/s/cm^2.

At the time of this 2nd trigger the position of 150201A was occulted by
the Earth to the Swift spacecraft. The GBM data suggest the two events may
have a common origin. Because of the uncertainty in the GBM localization,
we cannot exclude the possibility that this is a chance coincidence and
that GRB 150201590 is unrelated to GRB 150201A.

Owing to the possible relationship between the two triggers, which would make
this an unusually long GRB, Fermi is observing the position of GRB 150201A
as a target of opportunity for a period of 24 hours, subject to Earth limb
constraints.

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


GRB_name: GRB150201A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17371
SUBJECT: GRB 150201A: Swift-XRT refined Analysis
DATE:    15/02/02 09:00:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), B.P. Gompertz
(U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), M. de
Pasquale (INAF-IASFPA), M.C. Stroh (PSU), D.N. Burrows (PSU), J.A.
Kennea (PSU) and J.K. Cannizzo report on behalf of the Swift-XRT team:

We have analysed 7.9 ks of XRT data for GRB 150201A (Cannizzo et al.
GCN Circ. 17368), from 75 s to 51.9 ks after the  BAT trigger. The data
comprise 823 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. 17369).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=1.12 (+0.15, -0.13). At T+161 s  the decay
flattens to an alpha of 0.62 (+0.03, -0.04) before breaking again at
T+833 s to a final decay with index alpha=1.256 (+0.032, -0.026).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.86 (+/-0.04). The
best-fitting absorption column is  3.82 (+0.21, -0.20) x 10^21 cm^-2,
in excess of the Galactic value of 5.8 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.30 (+0.17, -0.16)
and a best-fitting absorption column of 4.7 (+0.8, -0.7) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.4 x 10^-11 (6.7 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      4.7 (+0.8, -0.7) x 10^21 cm^-2
Galactic foreground: 5.8 x 10^20 cm^-2
Excess significance: 9.3 sigma
Photon index:      2.30 (+0.17, -0.16)

If the light curve continues to decay with a power-law decay index of
1.256, the count rate at T+24 hours will be 0.037 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x
10^-12 (2.4 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/00629302.

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


GRB_name: GRB150201A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17372
SUBJECT: GRB 150201A: GROND upper limits
DATE:    15/02/02 14:54:42 GMT
FROM:    Fabian Knust at MPE/GROND  <fknust@mpe.mpg.de>

F. Knust, T. Schweyer, J. Bolmer, J. Greiner (all MPE Garching) report on behalf of the GROND team: 

We
 observed the field of GRB 150201A (Swift trigger 629302; J. K. Cannizzo
 et al., GCN #17368) simultaneously in g'r'i'z'JHK with GROND (Greiner 
et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La
 Silla Observatory (Chile). Observations
 started at  00:47 UT on 2015-02-02, 11hrs after the GRB trigger. They 
were performed at an average seeing of 1.64" and at an average airmass 
of 2.1. We do not detect a source within the Swift-XRT error circle reported by J.P. Osborne et al. (GCN #17369) down to 

g' > 23.2 mag, r' > 23.1 mag, i' > 23.5 mag, z' > 23.6 mag, J > 21.5 mag, H > 21.0 mag, and K > 19.4 mag. 
The
 given limits are derived based on calibrating the images against GROND 
zeropoints and 2MASS field stars and are not corrected for the Galactic 
foreground extinction corresponding to a reddening of E_(B-V)= 0.012 in 
the direction of the burst (Schlegel et al. 1998). 
            


GRB_name: GRB150201A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17373
SUBJECT: Konus-Wind observation of GRB 150201A
DATE:    15/02/02 17:10:25 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

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

The long-duration, intense GRB 150201A
(Swift BAT trigger 629302: Cannizzo et al., GCN 17368;
Fermi-GBM detection: Yu and Pelassa, GCN 17370)
triggered Konus-Wind at T0=49611.653 s UT (13:46:51.653).

The burst light curve shows a double-peaked pulse with a total duration 
of ~26 s.
The emission is seen up to ~10 MeV.
No post-burst activity was observed by Konus-Wind until ~T0+450s;
also, since the instrument switched to the read-out mode,
there are no triggered or waiting mode data available for the time
of the second GBM trigger 150201590 (14:09:56 UT; GCN 17370).

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150201_T49611/

As observed by Konus-Wind, the burst
had a fluence of 6.18(-0.22,+0.23)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+1.712 s,
of 2.10(-0.28,+0.30)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+22.272 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -1.20(-0.11,+0.13),
the high energy photon index beta = -2.89(-0.27,+0.17),
the peak energy 123(-6,+5) keV
(chi2 = 88/93 dof)

The spectrum near the maximum count rate
(measured from T0 to T0+2.048 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.77(-0.12,+0.14),
the high energy photon index beta = -2.47(-0.25,+0.17),
the peak energy 193(-20,+21) keV
(chi2 = 65/50 dof)

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


GRB_name: GRB150201A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17374
SUBJECT: GRB 150201A, Swift-BAT refined analysis
DATE:    15/02/02 18:23:30 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm@nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. K. Cannizzo (NASA/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 150201A (trigger #629302)
(Cannizzo, et al., GCN Circ. 17368).  The BAT ground-calculated position is
RA, Dec = 11.820 -37.620 deg which is
    RA(J2000)  = 00h 47m 16.8s
    Dec(J2000) =  -37d 37' 10"
with an uncertainty of 1.7 arcmin,(radius, sys+stat, 90% containment).
It is 0.6 arcmin from the XRT enhanced position. The partial coding was 3%.

The burst was outside the BAT calibrated field of view.  It came into the field
during the slew to point the narrow-field instruments. The earliest calibrated
event data starts at about T+22 s. The non-weighted light curve shows two main
peaks at about T-3 and T+1 seconds. The emission is detectable out to
approximately T+50 sec.  T90 (15-350 keV) is 26.1 +- 5.2 sec (estimated error 
including systematics).

The time-averaged spectrum from T+22.2 to T+49.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.32 +- 0.24.  The fluence in the 15-150 keV band is 7.8 +- 1.2 x 10^-07 
erg/cm2. This calibrated fluence is on the order of 5% of the total fluence.
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/629302/BA/


GRB_name: GRB150201A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17375
SUBJECT: GRB 150201A: Swift/UVOT Upper Limits
DATE:    15/02/02 19:29:53 GMT
FROM:    Frank Marshall at GSFC  <femarsha@khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and J. K. Cannizzo (CRESST/GSFC/UMBC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150201A
93 s after the BAT trigger (Cannizzo et al., GCN Circ. 17368).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 17369)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC            93          243          147         >21.0
u_FC               306          556          246         >20.4
white               93          913          239         >21.5
v                  635          829           39         >18.6
b                  561          755           35         >19.8
u                  306          729          265         >20.3
w1                 685          705           19         >19.6
w2                 784          804           19         >19.6

The magnitudes in the table 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: GRB150202A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17376
SUBJECT: GRB 150202A: Swift detection of a burst
DATE:    15/02/02 23:36:34 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC),
M. M. Chester (PSU), J. A. Kennea (PSU), K. L. Page (U Leicester),
D. M. Palmer (LANL), B. Sbarufatti (INAF-OAB/PSU) and
T. N. Ukwatta (LANL) report on behalf of the Swift Team:

At 23:10:02 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150202A (trigger=629547).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 39.236, -33.150, which is 
   RA(J2000)  =  02h 36m 57s
   Dec(J2000) = -33d 08' 59"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve show several peaks
swith a total duration of about 30 sec.  The peak count rate
was ~1600 counts/sec (15-350 keV), at ~4 sec after the trigger. 

The XRT began observing the field at 23:11:30.3 UT, 88.0 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 39.2275,
-33.1485 which is equivalent to:
   RA(J2000)  = 02h 36m 54.61s
   Dec(J2000) = -33d 08' 54.5"
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This
location is 26 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 (2.54 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.3
(+1.96/-1.74) x 10^21 cm^-2 (90% confidence). 

  UVOT took a finding chart exposure of 250 seconds with the U filter
starting  304 seconds after the BAT trigger. No credible afterglow
candidate has been  found in the initial data products. The 2.7'x2.7'
sub-image covers 100% of the  XRT error circle. The typical 3-sigma
upper limit has been about 19.2 mag. Data  from the list of sources
generated on-board are not available at this time. No  correction has
been made for the expected extinction corresponding to E(B-V) of 
0.02. 

Burst Advocate for this burst is H. A. Krimm (hans.krimm 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: GRB150203A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17377
SUBJECT: GRB 150203A: Swift detection of a burst
DATE:    15/02/03 04:23:40 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

T. N. Ukwatta (LANL), W. H. Baumgartner (GSFC/UMBC),
M. M. Chester (PSU), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU)
report on behalf of the Swift Team:

At 04:09:07 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150203A (trigger=629578).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 98.415, +6.968 which is 
   RA(J2000) = 06h 33m 39s
   Dec(J2000) = +06d 58' 04"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 30 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 04:10:21.5 UT, 74.0 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
98.3997, 6.9533 which is equivalent to:
   RA(J2000)  = 06h 33m 35.92s
   Dec(J2000) = +06d 57' 11.9"
with an uncertainty of 2.3 arcseconds (radius, 90% containment). This
location is 76 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 6.52
x 10^21 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 1.31e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 82 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 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 large, but uncertain extinction expected. 

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: GRB150203A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17378
SUBJECT: GRB 150203A: Prompt enhanced Swift-XRT position
DATE:    15/02/03 04:39:36 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Using  promptly downlinked XRT event data for GRB 150203A, we find an
enhanced XRT position of the afterglow: RA, Dec: 98.3993, 6.9532 which
is equivalent to:
   RA (J2000)  = 06 33 35.84
   Dec (J2000) = +06 57 11.5
with an uncertainty of 2.1 arcseconds (radius, 90% confidence).
Analysis of the promptly available data is online at
http://www.swift.ac.uk/sper/629578.

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: GRB150203A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17379
SUBJECT: GRB 150203A: KAIT Optical Upper Limit
DATE:    15/02/03 04:42:56 GMT
FROM:    Weikang Zheng at UC Berkeley  <zwk@astro.berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 150203A (Ukwatta et al.,
GCN 17377) starting at 04:10:55 UT, 108 s after the burst, with
thin cloud condition. Observations were performed with an automatic
sequence in the clear (roughly R), V, and I filters, and the
exposure time was 20 s per image. We do not detect any new source
neither in our single images, nor in the co-add of the first 5 images,
within the enhanced XRT error (Evans, GCN 17378). The typical
limiting magnitude of our single clear image is about 17.8 calibrated
to USNO B1.0.


GRB_name: GRB150203A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17380
SUBJECT: GRB 150203A: P60 observations
DATE:    15/02/03 04:55:19 GMT
FROM:    Daniel Perley at Caltech  <dperley@astro.caltech.edu>

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

The Palomar 60-inch robotic telescope responded to the Swift alert for 
GRB 150203A (Ukwatta et al., GCN 17377) and began automatic follow-up at 
04:11:42 UT, 155 s after the BAT trigger.  The telescope acquired a 
series of cycling 60-second r, i, and z exposures under good seeing 
conditions.

We detect no source in or near the XRT position (Evans et al., GCN 
17378), in any individual exposure or in a stack of the first several 
minutes of imaging acquired in each filter.  An approximate limiting 
magnitude of the r-band stack (7 minutes of imaging at a median time of 
13.0 minutes post-trigger) is >21.5 mag, calibrated relative to USNO B1.0.

Given the low galactic latitude, no further follow-up is planned.


GRB_name: GRB150202A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17381
SUBJECT: GRB 150202A: GROND Upper limits 
DATE:    15/02/03 05:23:59 GMT
FROM:    Corentin Delvaux at MPE  <delvaux@mpe.mpg.de>

C. Delvaux, K. Varela and J. Greiner (all MPE Garching) report on behalf
of the GROND team:

We observed the field of GRB 150202A (SWIFT-629547; Krimm et al., GCN
#17376) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started on February 3rd, 2015, at 00:43 UT, 1.5 hrs after the
GRB trigger. They were performed at an average seeing of 1.1" and at an
average airmass of 1.7.

We do not detect a source inside the 2.1 error circle reported by Krimm
et al. (GCN #17376). Based on a total exposure of 2.07 hours in
g'r'i'z'and 1.73 hours in JHK, at a midtime of 2 hours after the burst, we
measure the following preliminary upper limits (AB magnitudes system):

g' > 24.2 mag,
r' > 24.7 mag,
i' > 24.4 mag,
z' > 24.4 mag,
J  > 22.1 mag,
H  > 21.5 mag, and
K  > 18.0 mag.

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) = 0.02 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB150202A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17382
SUBJECT: GRB 150202A: Enhanced Swift-XRT position
DATE:    15/02/03 05:35:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 3966 s of XRT Photon Counting mode data and 6 UVOT
images for GRB 150202A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 39.22744, -33.14804 which is equivalent
to:

RA (J2000): 02h 36m 54.59s
Dec (J2000): -33d 08' 53.0"

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: GRB150203A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17383
SUBJECT: GRB 150203A: RATIR Optical and NIR Observations
DATE:    15/02/03 06:42:32 GMT
FROM:    Nat Butler at Az State U  <natbutler@asu.edu>

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), Jos A. de Diego (UNAM), Leonid Georgiev (UNAM), Jess
Gonzlez (UNAM), Carlos Romn-Ziga (UNAM), Neil Gehrels (GSFC), and
Harvey Moseley (GSFC) report:

We observed the field of GRB 150203A (Ukwatta, et al., GCN 17377) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronmico Nacional on
Sierra San Pedro Mrtir from 2015/02 3.19 to 2015/02 3.26 UTC (0.50 to 2.14
hours after the BAT trigger), obtaining a total of 1.28 hours exposure in
the r, i, and z bands.

We find no uncatalogued sources within the Swift-XRT error circle (Evans,
et al., GCN 17378).  In comparison with USNO-B1 and 2MASS, we obtain the
following upper limits (3-sigma):

  r > 23.1
  i > 23.3
  z > 20.1

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio Astronmico Nacional in San Pedro
Mrtir.


GRB_name: GRB150203A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17384
SUBJECT: GRB 150203A: Enhanced Swift-XRT position
DATE:    15/02/03 08:25:13 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1115 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 150203A, 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 = 98.39900, +6.95372 which is equivalent
to:

RA (J2000): 06h 33m 35.76s
Dec (J2000): +06d 57' 13.4"

with an uncertainty of 1.9 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) 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: GRB150202B
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17385
SUBJECT: GRB 150202B: Fermi-LAT detection
DATE:    15/02/03 08:25:40 GMT
FROM:    Magnus Axelsson at Stockholm U.  <magaxe@kth.se>

M. Axelsson (KTH Royal Institute of Technology, Stockholm) and G. Vianello (Stanford)
report on behalf of the Fermi-LAT team:

At 23:59:08.27 UT on February 2, 2015, Fermi-LAT detected
emission from GRB 150202B, which was also detected by Fermi-GBM
(trigger 444614351/150202999).

The GBM location was initially inside the LAT field of view at an angle of
~17 degrees to the LAT boresight and triggered an autonomous repoint
of the spacecraft. Using standard analysis procedures, we detect the GRB
with a significance barely above our 5-sigma threshold, when looking at
events >500 MeV in the interval 0s to 1300s relative to the trigger time. The
corresponding best location is

RA = 86.6 deg (J2000)
Dec = 59.1 deg (J2000)

with an estimated uncertainty of 0.4 degrees (90% containment). This is
0.5 deg from the GBM position.

Given the low significance, and the fact that there are only 4 photons compatible
with the position of the GBM trigger, we cannot firmly establish this excess as
the high-energy counterpart of GRB 150202B.

Using the LAT Low Energy (LLE) data selection, over 70 counts above
background were detected within a 20s interval coinciding with the time of
the GBM emission. This data selection has insufficient spatial resolution to
provide a reliable LAT localization. Since an excess of events was not firmly
seen using the standard analysis selection, this detection is likely due to low
energy gamma-rays (below 100 MeV).

The Fermi LAT point of contact for this burst is
Magnus Axelsson (magnus.axelsson@astro.su.se<mailto:magnus.axelsson@astro.su.se>).

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.

[GCN OPS NOTE(03feb15):  Per author's request, the "0127A" was changed to "202B"
in the phrase "counterpart of GRB 150202B".]


GRB_name: GRB150203A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17386
SUBJECT: GRB 150203A: GROND Upper limits
DATE:    15/02/03 08:54:48 GMT
FROM:    Karla Varela at MPE  <kvarela@mpe.mpg.de>

C. Delvaux, K. Varela and J. Greiner (all MPE Garching) report on behalf
of the GROND team:

We observed the field of GRB 150203A (SWIFT-629578; Ukwatta et al., GCN
#17377) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started on February 3rd, 2015, at 04:20 UT, 11 minutes after
the GRB trigger. They were performed at an average seeing of 1.2" and at
an average airmass of 2.1. The distance from the moon was only 28 deg.

We do not detect a source inside the 2.1 arcsec error circle reported by
Ukwatta et al. (GCN #17377). Based on a total exposure of 0.83 hours in
g'r'i'z'
and 0.80 hours in JHK, at a midtime of 0.7 hour after the burst, we measure
the following preliminary upper limits (AB magnitudes system):

g' > 23.5 mag,
r' > 23.9 mag,
i' > 24.0 mag,
z' > 24.1 mag,
J > 21.5 mag,
H > 20.9 mag, and
K > 18.6 mag.

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) = 0.88 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB150203A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17387
SUBJECT: GRB 150203A: TAROT La Silla observatory optical observations
DATE:    15/02/03 10:41:40 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

Klotz A., Turpin D. (IRAP-CNRS-OMP),
Boer M., Gendre B., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA),
Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 150203A detected by SWIFT
(trigger 629578) with the TAROT robotic telescope (D=25cm)
located at the European Southern Observatory,
La Silla observatory, Chile.

The observations started 37.1s after the GRB trigger
(13.6s after the notice). The elevation of the field decreased from
45 degrees above horizon and weather conditions
were good but the field of view is located at low
galactic latitude (extinction estimated > 14 magnitudes
in the R band).

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT with a limiting magnitude of:
t0+37.1s to t0+97.1s : Rlim = 15.8

The second image is 90.0s exposure in tracking mode:
t0+391s to t0+481s : Rlim = 16.4

We co-added a series of exposures:
t0+391s to t0+1203s : Rlim = 17.0

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

N.B. Galactic coordinates are lon=204.7072 lat= -0.7535


GRB_name: GRB150202B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17388
SUBJECT: GRB 150202B: Fermi GBM detection
DATE:    15/02/03 11:08:57 GMT
FROM:    Hoi-Fung Yu at MPE  <sptfung@mpe.mpg.de>

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

"At 23:59:08.27 UT on 02 Feb 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150202B (trigger 444614351 / 150202999).

The on-ground calculated location, using the GBM trigger data, is
RA = 86.8, Dec = 58.6 (J2000 degrees, equivalent to +05h 47m, +58d 32'),
with an uncertainty of 1.0 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT
boresight is 17 degrees.  This trigger resulted in an Autonomous Repoint
Request (ARR) that was not accepted by the spacecraft.  Following
this observation the Fermi Large Area Telescope also detected
this burst in the ground-based analysis (Axelsson et al. 2015, GCN 17385).

This GRB was also detected by Integral/SPI-ACS.

The GBM light curve consists of a bright peak lasting about 25 s, 
followed at T0+ 100 s by a fainter second episode of emission, 
with a total duration (T90) of about 167 s (50-300 keV). 
The 1.024-sec peak photon flux measured starting from T0+7.808 s 
in the 10-1000 keV band is 23.8 +/- 0.4 ph/s/cm^2.

The time-averaged spectrum of the first episode, from T0-5.120 s to
T0+24.576 s, is best fit by a Band function with Epeak = 253 +/- 12 keV,
alpha = -0.82 +/- 0.02, and beta = -2.36 +/- 0.13. The event fluence 
(10-1000 keV) in this time interval is (3.15 +/- 0.05)E-05 erg/cm^2.

The time-averaged spectrum of the second episode, from T0+103.426 s to
T0+205.827 s, is well fit a power law function with an exponential
high-energy cutoff. The power law index is -1.23 +/- 0.13 and
the cutoff energy, parameterized as Epeak, is 154 +/- 36 keV. 
The event fluence (10-1000 keV) in this time interval 
is (1.37 +/- 0.15)E-06 erg/cm^2.

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

[GCN OPS NOTE(03feb15): The third sentence in the second paragraph
was changed to say the ARR was rejected by the spacecraft.]


GRB_name: GRB150203A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17389
SUBJECT: GRB 150203A: Fermi GBM observation
DATE:    15/02/03 11:09:45 GMT
FROM:    Hoi-Fung Yu at MPE  <sptfung@mpe.mpg.de>

V. Pelassa (UAH) and H.-F. Yu (MPE) report on behalf of the Fermi GBM Team:

"At 04:09:10.06 UT on 03 Feb 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150203A (trigger 444629353 / 150203173), which
was also detected by Swift (Ukwatta et al. 2015, GCN 17377). The GBM
on-ground location is consistent with the Swift position. The angle from
the Fermi LAT boresight is 97 degrees.

The GBM light curve shows a single pulse with a duration (T90) of
about 26 s (50-300 keV). The time-averaged spectrum from T0-2.048 s
to T0+ 27.648 s is well fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.82 +/- 0.32 and the cutoff
energy, parameterized as Epeak, is 59 +/- 8 keV.

The event fluence (10-1000 keV) in this time interval is
(1.29 +/- 0.13)E-06 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0+13.952 s in the 10-1000 keV band is 1.8 +/- 0.3 ph/s/cm^2.

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


GRB_name: GRB150202A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17390
SUBJECT: GRB 150202A: Swift-XRT refined Analysis
DATE:    15/02/03 11:36:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), B.P. Gompertz (U. Leicester), V. D'Elia
(ASDC), M. de Pasquale (INAF-IASFPA), A. Maselli  (INAF-IASFPA), D.N.
Burrows (PSU), J.A. Kennea (PSU), V. Mangano (PSU), J.P. Osborne (U.
Leicester) and H.A. Krimm report on behalf of the Swift-XRT team:

We have analysed 6.0 ks of XRT data for GRB 150202A (Krimm et al. GCN
Circ. 17376), from 98 s to 24.9 ks after the  BAT trigger. The data are
entirely in Photon Counting (PC) mode. The enhanced XRT position for
this burst was given by Beardmore et al. (GCN Circ. 17382).

The light curve can be modelled with an initial power-law decay with an
index of alpha=0.62 (+0.12, -0.13), followed by a break at T+1352 s to
an alpha of 1.26 (+0.30, -0.11).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.00 (+/-0.17). The
best-fitting absorption column is  1.7 (+0.6, -0.5) x 10^21 cm^-2, in
excess of the Galactic value of 2.5 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.5 x 10^-11 (4.6 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.7 (+0.6, -0.5) x 10^21 cm^-2
Galactic foreground: 2.5 x 10^20 cm^-2
Excess significance: 4.6 sigma
Photon index:      2.00 (+/-0.17)

If the light curve continues to decay with a power-law decay index of
1.26, the count rate at T+24 hours will be 2.5 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.5 x
10^-14 (1.1 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/00629547.

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


GRB_name: GRB150203A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17391
SUBJECT: GRB 150203A: REM optical and NIR observations
DATE:    15/02/03 16:21:15 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, S. Covino (INAF-OAB), V. D'Elia (ASI/ASDC & INAF/OAR) report on behalf of the REM team: 

We observed the field of GRB 150203A (Ukwatta et al., GCN 17377) with the 60-cm robotic telescope
REM located at the La Silla Observatory (Chile). The observations started at 04:10:09 UT, 62 seconds 
after the GRB, and were carried out simultaneously with in the g, r, i, z and H bands.

No source is detected at the X-ray afterglow position reported by Evans et al. (GCN 17384). 
At a mean t-t0 of 181 s, we obtain the following 3sigma upper limits: 

g > 17.8 mag
r > 17.7 mag
i > 17.5 mag
H > 17.5 mag

All magnitudes are in the AB system and are not corrected for Galactic reddening. 
The photometry is calibrated against the APASS (optical) and 2MASS (NIR) catalogues.


GRB_name: GRB150202A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17392
SUBJECT: GRB 150202A: Swift/UVOT Upper Limits
DATE:    15/02/03 19:14:39 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

M. M. Chester (PSU) and H. A. Krimm (CRESST/GSFC/USRA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150202A
93 s after the BAT trigger (Krimm et al., GCN Circ. 17376).
No optical afterglow consistent with the XRT position (Beardmore et al. 
GCN Circ. 17382) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC            93          243          147         >20.6
u_FC               305          555          246         >20.2
white               93         6568          624         >21.5
v                  634         6980          530         >20.4
b                  560         7617          350         >21.3
u                  305         7594          756         >20.7
w1                 683         7390          510         >20.9
m2                 658         7185          452         >21.7
w2                 610         6774          490         >20.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150204A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17394
SUBJECT: Swift Trigger 629693: probably not real
DATE:    15/02/04 00:34:54 GMT
FROM:    David Burrows at PSU/Swift  <burrows@astro.psu.edu>

M. H. Siegel (PSU), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC),
C. Gronwall (PSU) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of
the Swift Team:

At 00:12:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150204A (trigger=629693).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 207.806, -8.686 which is 
   RA(J2000) = 13h 51m 13s
   Dec(J2000) = -08d 41' 08"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  This was an image trigger and, as usual for such
events, does not show any noticeable structure. 

The XRT began observing the field at 00:15:04.5 UT, 141.7 seconds after
the BAT trigger. No source was detected in 468 s of promptly downlinked
data. We are waiting for the full dataset to detect and localise the
XRT counterpart. 

UVOT took a finding chart exposure of  58 seconds with the White filter
starting 858 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
0.04. 

Given the lack of a bright XRT source, it is likely that this is a
noise event and not an astrophysical source.  The full ground-linked
data set will be necessary to verify. 

Burst Advocate for this burst is M. H. Siegel (siegel AT swift.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: GRB150203A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17395
SUBJECT: GRB 150203A: MITSuME Okayama upper limits
DATE:    15/02/04 01:43:25 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 MITSuME and OISTER collaboration:

We observed the field of GRB 150203A (Ukwatta et al., GCNC 17377)
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 2015-02-03 10:36:11 UT (~6.5 h after the burst).
We did not find any new point source within the enhanced XRT circle
(Evans et al., GCNC 17384) 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
-----------------------------------------------------
0.36578    12:55:51    6060.0   >19.8  >19.5  >18.7
-----------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]


GRB_name: GRB150202B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17396
SUBJECT: GRB 150202B: Tiled Swift observations
DATE:    15/02/04 01:47:19 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
Fermi/LAT GRB 150202B. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00039

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the Fermi/LAT event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

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


GRB_name: GRB150203A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17397
SUBJECT: GRB 150203A: Swift-XRT refined Analysis
DATE:    15/02/04 04:23:04 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

B.P. Gompertz (U. Leicester), M. de Pasquale (INAF-IASFPA), A. Maselli 
(INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU), V. Mangano
(PSU), M.C. Stroh (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester) and T.N. Ukwatta report on behalf of the Swift-XRT team:

We have analysed 5.7 ks of XRT data for GRB 150203A (Ukwatta et al. GCN
Circ. 17377), from 64 s to 24.0 ks after the  BAT trigger. The data
comprise 76 s in Windowed Timing (WT) mode (the first 8 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. 17378).

The light curve can be modelled with an initial power-law decay with an
index of alpha=2.84 (+0.15, -0.13), followed by a break at T+355 s to
an alpha of 0.59 (+0.09, -0.08).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.87 (+0.29, -0.27). The
best-fitting absorption column is  1.20 (+0.35, -0.30) x 10^22 cm^-2,
in excess of the Galactic value of 6.5 x 10^21 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.1 (+0.4, -0.3) and
a best-fitting absorption column of 1.5 (+0.5, -0.4) x 10^22 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 5.3 x 10^-11 (1.2 x 10^-10) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.5 (+0.5, -0.4) x 10^22 cm^-2
Galactic foreground: 6.5 x 10^21 cm^-2
Excess significance: 3.5 sigma
Photon index:      2.1 (+0.4, -0.3)

If the light curve continues to decay with a power-law decay index of
0.59, 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 5.6 x
10^-13 (1.2 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/00629578.

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


GRB_name: GRB150202B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17398
SUBJECT: IPN Triangulation of GRB 150202B
DATE:    15/02/04 10:04:20 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,

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

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C.
Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and

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

The long-duration GRB 150202B (Axelsson and Vianello., GCN Circ. 17385) 
has been detected by Fermi (Pelassa., GCN Circ. 17388), Konus-Wind, 
MESSENGER (GRNS), INTEGRAL (SPI-ACS), and Swift (BAT), so far, at about 
86348 s UT (23:59:08). The burst was outside the coded field of view of 
the BAT.

We have triangulated it to a Konus-MESSENGER annulus centered at 
RA(2000)=126.992 deg (08h 27m 58s)  Dec(2000)=+15.280 deg (+15d 16' 
50"), whose radius is 52.564 +/- 0.201 deg (3 sigma).

The annulus intersects the LAT (statistical-only) error circle (GCN 
17385) thereby confirming the association of the high-energy emission 
with GRB 150202B. The area of the combined IPN/LAT error region is 570 
sq. arcmin.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB150202_T86354/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming 
GCN Circular.


GRB_name: GRB150203A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17399
SUBJECT: GRB 150203A: ISON-NM early optical limit
DATE:    15/02/04 11:46:45 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

L. Elenin (KIAM),  A. Volnova (IKI), E. Mazaeva (IKI),  I. Molotov  (KIAM), 
A. Pozanenko (IKI) report on behalf of larger GRB  follow-up  collaboration:

We observed the field of the Swift GRB 150203A (Ukwatta et al., GCN 17377) 
with 0.4-m telescope of ISON-NM observatory in robotic mode starting on 
Feb., 03 (UT) 04:10:19  i.e. 72 seconds after burst trigger. We obtained 60 
unfiltered images of 30 s exposure. We do not detect any source within 
enhanced XRT error circle (Evans et al., GCN 17384):

Date          UT start   t-T0             Exp.    Filter   UL (3sigma)
                               (mid.,days)    (s)
2014-02-03 04:10:19  0.00130       2*30    Clear   18.0
2014-02-03 04:10:19  0.01836     60*30    Clear   19.7

The photometry is based on nearby USNO-B1.0  stars

USNO-B1.0    RA              Dec             R2
0968-0105340 06:33:22.23 +06:53:43.2 15.41
0969-0108800 06:33:26.73 +06:56:58.4 14.77
0969-0108730 06:33:22.76 +06:55:10.3 15.73 


GRB_name: GRB150203A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17400
SUBJECT: GRB 150203A:  Swift/UVOT Upper Limits
DATE:    15/02/04 13:38:23 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

M. M. Chester (PSU) and T. N. Ukwatta (LANL) report on behalf of the 
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150203A
83 s after the BAT trigger (Ukwatta et al., GCN Circ. 17377).
No optical afterglow consistent with the enhanced XRT position 
(Evans et al. GCN Circ. 17384) is detected in the initial UVOT 
exposures.  Preliminary 3-sigma upper limits using the UVOT 
photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) 
for the first finding chart (FC) exposures and subsequent exposures are:

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

white_FC         83         232         147     >20.6
white            83        1197         353     >21.2 
v               624        1246          78     >18.7
b               550        1172          58     >19.4
u_FC            295         545         246     >20.0
u               295        1148         285     >20.0
w1              674        1278          61     >18.8
m2              649        1271          78     >18.7
w2              600        1222          78     >19.0

The magnitudes in the table are not corrected for the large Galactic 
extinction in the direction of the burst (reddening of E(B-V) = 0.9; 
Schlegel et al. 1998).


GRB_name: GRB150202A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17401
SUBJECT: GRB 150202A, Swift-BAT refined analysis
DATE:    15/02/04 14:19:35 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm@nasa.gov>

T. Sakamoto (AGU), S. D. Barthelmy (GSFC),  W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
M. Stamatikos (OSU), T. N. Ukwatta (LANL) (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 150202A (trigger #629547)
(Krimm, et al., GCN Circ. 17376).  The BAT ground-calculated position is
RA, Dec = 39.261, -33.132 deg which is
    RA(J2000)  =  02h 37m 02.6s
    Dec(J2000) = -33d 07' 56.1"
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 60%.

The mask-weighted light curve shows a complex structure with multiple peaks. The 
first emission episode runs from T-2 to T+10 sec and then second episode from 
T+12 to ~T+30 sec. T90 (15-350 keV) is 25.7 +- 4.3 sec (estimated error 
including systematics).

The time-averaged spectrum from T-1.7 to T+27.1 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.50 +- 0.19.  The fluence in the 15-150 keV band is 6.1 +- 0.7 x 10^-7 erg/cm2. 
The 1-sec peak photon flux measured from T+17.40 sec in the 15-150 keV band is 
1.0 +- 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/629547/BA/


GRB_name: GRB150203A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17402
SUBJECT: GRB 150203A: RAPTOR Limits Beginning at the Gamma-Ray Emitting Interval
DATE:    15/02/04 15:53:14 GMT
FROM:    James Wren at LANL  <jwren@nis.lanl.gov>

J. Wren, W.T. Vestrand, P. Wozniak, and H. Davis,
of Los Alamos National Laboratory report:

The RAPTOR network of robotic optical telescopes made observations of Swift trigger 629578 (Ukwatta, et al., GCN 17377).  Our narrow-field instruments located in Los Alamos, NM, USA, arrived on target 4.6 s after receipt of the notice (T+30.9 s after the BAT trigger time).  No optical counterpart is detected within the Swift XRT counterpart location.  Typical 3-sigma limiting magnitudes for our initial 5 s exposures were R~16.6 and I~15.7 based on comparision to the USNO-B1 R-band catalog.

The burst location was also within the field of view of our wide-field sky monitors during the gamma-ray emitting interval.  No optical counterpart is detected in any of our wide-field monitor images.  Typical 3-sigma unfiltered limiting magnitudes during this period were V~9.7 based on comparison to the
Tycho-2 V-band catalog.


GRB_name: GRB150204A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17404
SUBJECT: GRB 150204A found in ground analysis of Swift-BAT data
DATE:    15/02/04 18:11:41 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

J. R. Cummings (CPI.com) on behalf of the Swift science team

At 06:31:08, a GRB occurred during a preplanned Swift slew.  This was the same
event as Fermi GBM trigger 444724270.  A mosaic of images from BAT photon event
data revealed a bright source at RA, Dec 160.241, -64.043, which is:

RA (J2000)   10h 40m 57.8s
Dec (J2000) -64d 02' 34"

with an estimated 90% uncertainty radius of 1.5 arcmin.

The burst was a single symmetric cusp that lasted about 13 seconds.

A Swift TOO has been requested.


GRB_name: GRB150202B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17405
SUBJECT: GRB 150202B: Swift XRT/UVOT observations
DATE:    15/02/04 19:37:11 GMT
FROM:    Boris Sbarufatti at INAF-OAB/IASFPA  <boris.sbarufatti@brera.inaf.it>

B. Sbarufatti (INAF-OAB/PSU), F. E. Marshall (NASA/GSFC), A. Maselli 
(INAF-IASFPA), A. Melandri (INAF-OAB), V. Mangano (PSU), M.C. Stroh
(PSU), D.N. Burrows (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), C. Pagani (U. Leicester) and P.A. Evans (U. Leicester)
report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 150202B (Axelsson et al. GCN Circ. 17385)
in a series of observations tiled on the sky. The total exposure time
is 4.2 ks, distributed over 2 tiles; the maximum exposure at a single
sky location was 4.7 ks. The data were collected between T0+95.4 ks and
T0+107.3 ks, and are entirely in Photon Counting (PC) mode. 

Four uncatalogued X-ray sources have been detected, however none of
them is above the RASS limit or shows definitive signs of fading.
Therefore, at the present time we cannot identify which, if any, is the
afterglow. Details of these sources are given below:

Source 1:
  RA (J2000):  86.9565  =  05:47:49.57
  Dec (J2000): +58.8301  =  +58:49:48.2
  Error: 4.1 arcsec (radius, 90% conf.)
  Count-rate: 0.0183 +/- 0.0030 ct s^-1
  Flux: (6.1 +/- 1.0)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 2:
  RA (J2000):  86.5922  =  05:46:22.14
  Dec (J2000): +58.9223  =  +58:55:20.5
  Error: 5.7 arcsec (radius, 90% conf.)
  Count-rate: (5.9 +/- 1.9) -3 ct s^-1
  Flux: (3.2 +/- 1.0)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 3:
  RA (J2000):  86.7927  =  05:47:10.25
  Dec (J2000): +58.7852  =  +58:47:06.8
  Error: 6.4 arcsec (radius, 90% conf.)
  Count-rate: (4.0 +/- 1.7) -3 ct s^-1
  Flux: (1.60 +/- 0.67)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 4:
  RA (J2000):  86.8219  =  05:47:17.25
  Dec (J2000): +58.9746  =  +58:58:28.7
  Error: 5.5 arcsec (radius, 90% conf.)
  Count-rate: (3.03 +/- 0.99) -3 ct s^-1
  Flux: (6.5 +/- 2.1)e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Sources 3 and 4 are positionally coincident with stars from the USNO B1
catalogue.

The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at http://www.swift.ac.uk/xrt_products/TILED_GRB00039.

The UVOT observation covers sources 1 and 3 in the UVW1 filter. There
is nothing at the position of source 1; source 3 is bright as expected
from the catalogued source.

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


GRB_name: GRB150204A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17406
SUBJECT: GRB 150204A BAT refined analysis
DATE:    15/02/04 19:53:28 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

M. Stamatikos (OSU), C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (CPI.com), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL),
T. Sakamoto (AGU),  J. Tueller (GSFC),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

We report further analysis of GRB 150204A.  The best BAT position is the same
as reported earlier (Cummings, GCN # 17404), RA, Dec 160.241, -64.043, which is:

RA (J2000)   10h 40m 57.8s
Dec (J2000) -64d 02' 34"

with an estimated 90% uncertainty radius of 1.5 arcmin.  The source was 77% coded
at the time of the burst.

The burst was a single symmetric cusp.  T90 was 12 +- 2 seconds.

A simple powerlaw function is the best fit to the BAT spectrum.  The photon index
is 1.62 +- 0.10.  The fluence from 15 to 150 keV in 13 seconds was
(8.0 +- 0.4) x 10^-7 ergs/cm^2.  The 1-second peak flux in this energy range was
1.85 +- 0.12 photons/cm^2.  All uncertainties are 90% confidence.

A Swift TOO has been approved.


GRB_name: GRB150204A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17407
SUBJECT: GRB 150204A: Swift ToO observations
DATE:    15/02/04 20:55:20 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the Swift/BAT GRB 150204A. 
Automated analysis of the XRT data will be presented online at
http://www.swift.ac.uk/ToO_GRBs/00020477

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Swift/BAT event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a 
GCN Circular after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

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


GRB_name: GRB150204A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17408
SUBJECT: GRB 150204A: Fermi GBM detection
DATE:    15/02/04 21:17:10 GMT
FROM:    Eric Burns at U of Alabama  <eb0016@uah.edu>

E. Burns (UAH) and H.-F. Yu (MPE)
report on behalf of the Fermi GBM Team:

"At 06:31:07.88 UT on 04 February 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150204A (trigger 444724270 / 150204272) which
was also found in ground analysis of Swift/BAT data
(Cummings et al. 2015, GCN 17404). The GBM on-ground location is
consistent with the Swift position. The angle from the Fermi LAT boresight
is 54 degrees.

The GBM light curve consists of one main peak
with a duration (T90) of about 10 s (50-300 keV).
The time-averaged spectrum from T0-6.144 s to T0+7.168 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.4 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 350 +/- 143 keV

The event fluence (10-1000 keV) in this time interval is
(2.2 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.064 s in the 10-1000 keV band
is 3.1 +/- 0.2 ph/s/cm^2.

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


GRB_name: GRB150204A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17409
SUBJECT: GRB 150204A: Swift-XRT observations
DATE:    15/02/05 15:31:28 GMT
FROM:    Boris Sbarufatti at INAF-OAB/IASFPA  <boris.sbarufatti@brera.inaf.it>

A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), M.C. Stroh (PSU),
D.N. Burrows (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), C.
Pagani (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo
(INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Swift/BAT-detected burst GRB 150204A (Cummings et al. GCN Circ. 17404),
collecting 4.4 ks of Photon Counting (PC) mode data between T0+51.2 ks
and T0+63.6 ks. 

One uncatalogued X-ray source has been detected inside or close to the
Swift/BAT error region, it is below the RASS limit and shows no
definitive signs of fading. Therefore, at the present time we cannot
confirm this as the afterglow. Details of this source are given below:

Source 2:
  RA (J2000):  160.2373  =  10:40:56.94
  Dec (J2000): -64.0387  =  -64:02:19.4
  Error: 4.8 arcsec (radius, 90% conf.)
  Count-rate: (8.9 +/- 1.8)e-3 ct s^-1
  Flux: (3.69 +/- 0.75)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
http://www.swift.ac.uk/ToO_GRBs/00020477.

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


GRB_name: GRB150203A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17410
SUBJECT: GRB 150203A: Swift-BAT refined analysis
DATE:    15/02/05 15:36:38 GMT
FROM:    Tilan Ukwatta at MSU  <tilan.ukwatta@gmail.com>

T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), J. Tueller (GSFC),
(i.e. the Swift-BAT team):

Using the data set from T-120 to T+1190 sec from the
recent telemetry downlink, we report further analysis of
BAT GRB GRB 150203A (trigger #629578) (Ukwatta, et al.,
GCN Circ. 17377).The BAT ground-calculated position is
RA, Dec = 98.394, 6.952 deg which is
   RA(J2000)  =  06h 33m 34.5s
   Dec(J2000) = +06d 57' 07.1"
with an uncertainty of 1.1 arcmin, (radius, sys+stat,
90% containment). The partial coding was 84%.

BAT light curve shows a single multi-peaked episode starting
around T-2 sec, and ending around T+32 sec. The two main
peaks of the light curve can be seen at T+1 sec and T+18 sec.
T90 (15-350 keV) is 25.8 +- 5.0 sec (estimated error
including systematics).

The time-averaged spectrum from T-0.8 to T+32.3 sec
is best fit by a simple power-law model.  The power law
index of the time-averaged spectrum is 1.90 +- 0.12.
The fluence in the 15-150 keV band is 9.1 +- 0.6 x 10^-07
erg/cm2. The 1-sec peak photon flux measured from T+16.79
sec in the 15-150 keV band is 0.9 +- 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/629578/BA/


GRB_name: GRB150204A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17411
SUBJECT: GRB 150204A: Swift/UVOT Upper Limits
DATE:    15/02/05 16:42:34 GMT
FROM:    Alice Breeveld at MSSL-UCL  <a.breeveld@ucl.ac.uk>

A. Breeveld (MSSL-UCL), D. Malesani (DARK/NBI) and B. Sbarufatti 
(INAF-OAB/PSU) report on behalf of the Swift/UVOT team:

The Swift/UVOT observed the field of GRB 150204A during follow-up 
observations, 51182 s after the BAT trigger (Cummings et al. GCN Circ. 
17404). No optical afterglow consistent with the possible XRT 
counterpart (A. Melandri et al. GCN Circ. 17409) is detected in the 
initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial 
exposures are:

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

v                57368        58276          885         >19.5
u                52088        52670          568         >19.5
w1               51182        63642         1495         >20.3
m2               58281        63016         1027         >20.1
w2               56461        57361          886         >19.9

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.824 in the direction of 
the burst (Schlegel et al. 1998).


GRB_name: GRB150204A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17412
SUBJECT: GRB 150204A: LCOGT-Sutherland and Siding Springs observations
DATE:    15/02/05 19:37:30 GMT
FROM:    Simone Dichiara at Ferrara U/Italy  <dichiara@fe.infn.it>

S. Dichiara, C. Guidorzi (U. Ferrara), D. Kopac,
A. Gomboc (U. Ljubljana), C.G. Mundell (LJMU),
on behalf of a large collaboration report:

Two of the Las Cumbres Observatory 1-m telescopes in Sutherland
(South Africa) began observing simultaneously Swift and Fermi
GRB 150204A (Cummings et al. GCN 17404; Burns & Yu GCN 17408)
on February 04 at 19:47:41 UT, i.e. ~13.3 hours after the GRB,
with the r' and i' filters.
We re-observed with two 1-m telescopes in Siding Springs
(Australia) starting on February 05 at 13:58:33 (~31.4 hours)
with the same filters.

Within the XRT error circle (Melandri et al. GCN 17409)
we found no new source down to the following limit:

Mid time from  Total Exp   Filter    Magnitude
trigger (hr)   (s)
-------------------------------------------------
13.37          120x10      r'         > 19.6
13.56          120x10      i'         > 18.6
-------------------------------------------------

We found two uncatalogued sources close to the XRT error circle
at RA=10:40:55.98 Dec=-64:02:26.01 and RA=10:40:56.51 Dec=-64:02:13.8 (J2000)
with magnitudes r=19.68 +- 0.13 i=18.32 +- 0.13, r=19.47 +- 0.12
i=18.23 +- 0.12, respectively. However, image subtraction revealed
no significant variation between the two epochs.
The same conclusion holds for the entire BAT error circle
(Stamatikos et al. GCN 17406).
Magnitudes are calibrated against nearby USNO-B1 R2 and I
values.


GRB_name: GRB150206A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17413
SUBJECT: GRB 150206A: Swift detection of a burst with an optical afterglow
DATE:    15/02/06 15:05:06 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

L. M. Z. Hagen (PSU), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), P. A. Evans (U Leicester),
N. Gehrels (NASA/GSFC), C. Gronwall (PSU), M.E. Gropp (PSU),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
D. M. Palmer (LANL), B. Sbarufatti (INAF-OAB/PSU) and
M. H. Siegel (PSU) report on behalf of the Swift Team:

At 14:30:02 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150206A (trigger=630019).  Swift did not immediately slew
due to observing constraint.  The BAT on-board calculated location is 
RA, Dec 10.088, -63.182, which is 
   RA(J2000)  =  00h 40m 21s
   Dec(J2000) = -63d 10' 53"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a weak beginning
with a strong increase starting at ~T+70 sec.  The duration is 
about 150 sec.  The peak count rate was ~8000 counts/sec (15-350 keV),
at ~97 sec after the trigger. 

The XRT began observing the field at 14:37:57.3 UT, 474.5 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 10.0774, -63.1852 which is equivalent to:
   RA(J2000)  = +00h 40m 18.58s
   Dec(J2000) = -63d 11' 06.7"
with an uncertainty of 5.1 arcseconds (radius, 90% containment). This
location is 20 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 2.35e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of  94 seconds with the White filter
starting 483 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 00:40:17.66 =  10.07358
  DEC(J2000) = -63:10:55.6  = -63.18211
with a 90%-confidence error radius of about 0.78 arc sec. This position is 12.7
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.62 with a 1-sigma error of about  0.16. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02. 

Burst Advocate for this burst is L. M. Z. Hagen (lea.zernow.hagen 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: GRB150206A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17414
SUBJECT: GRB 150206A: MAXI/GSC detection
DATE:    15/02/06 16:27:56 GMT
FROM:    H. Negoro at Nihon U.  <negoro@phys.cst.nihon-u.ac.jp>

H. Negoro (Nihon U.), S. Ueno, H. Tomida, S. Nakahira, M. Kimura, M. Ishikawa, 
Y. E. Nakagawa (JAXA), T. Mihara, M. Sugizaki, M. Serino, M. Morii, 
J. Sugimoto, T. Takagi, A. Yoshikawa, M. Matsuoka (RIKEN),
N. Kawai, T. Yoshii, Y. Tachibana (Tokyo Tech), 
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU),
H. Tsunemi, D. Uchida (Osaka U.), M. Nakajima, K. Fukushima, T. Onodera, 
K. Suzuki, M. Fujita, F. Honda, T. Namba (Nihon U.),
Y. Ueda, M. Shidatsu, T. Kawamuro, T. Hori (Kyoto U.),
Y. Tsuboi, A. Kawagoe (Chuo U.), M. Yamauchi, Y. Morooka, D. Itoh (Miyazaki U.),
K. Yamaoka (Nagoya U.) report on behalf of the MAXI team:

We report the MAXI/GSC detection of GRB 150206A (Hagen et al. GCN 17413) 
in the scan transit at 14:50 on 2015 February 06 UT, about 20 min after
the BAT trigger.

Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (10.174 deg, -63.382 deg) = (00 40 41, -63 22 55) (J2000) 
with a statistical 90% C.L. elliptical error region 
with long and short radii of 0.34 deg and 0.28 deg respectively. 
The roll angle of long axis from the north direction is 82.0 deg 
counterclockwise. There is an additional systematic uncertainty of 0.1 deg 
(90% containment radius). 
The position is consistent with that of GRB 150206A.

The X-ray flux averaged over the scan was 116 +- 25 mCrab (4-10keV, 1 sigma 
error). 
There was no significant excess flux in the previous transit at UT 13:21
with an upper limit of 20 mCrab.


GRB_name: GRB150206B
Detection_method: iPTF
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17415
SUBJECT: GRB 150206B: iPTF Optical Observations 
DATE:    15/02/06 21:06:32 GMT
FROM:    Leo Singer at GSFC/iPTF  <leo.p.singer@nasa.gov>

L. P. Singer (NASA/GSFC), M. M. Kasliwal (Carnegie Observatories/Princeton),
and S. B. Cenko (NASA/GSFC) report on behalf of the intermediate Palomar
Transient Factory (iPTF) collaboration:

Fermi detected GRB 150206B (Fermi trigger 444908790 / bn150206407) at
2015-02-06 09:46:27.48. At 2015-02-06 10:23:45, 37 minutes after the
burst, we began searching for optical counterparts using the Palomar
48-inch Oschin telescope (P48).

We imaged 20 fields covering an area of 144 deg^2 mostly inside the
1-sigma statistical+systematic region of the final Fermi GBM localization.
We estimate a 51% prior probability that these fields contain the true
location of the source. Sifting through candidate variable sources using
image subtraction and standard iPTF vetting procedures, we detected the
following optical transient candidates:

iPTF15gz, at the coordinates:
  RA(J2000)  =  13h 47m 18.31s (206.826292 deg)
  Dec(J2000) = +55d 38' 33.7"  (+55.642694 deg)
No source is visible at this position in archival SDSS and iPTF images.
The following P48 photometry is suggestive of fading:
  +116.7 min:   R = 20.25 +/- 0.13
  +160.7 min:   R = 20.54 +/- 0.19

iPTF15hb, at the coordinates:
  RA(J2000)  =  14h 07m 09.34s (211.788915 deg)
  Dec(J2000) = +63d 02' 20.6"  (+63.039047 deg)
This position is near the galaxy SDSS J140709.19+630218.3, with photoZ ~ 0.2
suggesting an absolute magnitude of M_R ~ -21, consistent with typical
optical afterglows. We report the following photometry:
  +98.20 min:   R = 18.94 +/- 0.05
  +142.2 min:   R = 18.87 +/- 0.04
  +186.3 min:   R = 19.00 +/- 0.04

iPTF15gv, at the coordinates:
  RA(J2000)  =  14h 15m 28.31s (213.867960 deg)
  Dec(J2000) = +58d 24' 47.8"  (+58.413284 deg)
This coincides with the galaxy SDSS J141527.96+582447.9, with photoZ ~ 0.085,
suggesting M_R ~ -18. Although this is fainter than a typical optical
afterglow, the source is rapidly fading:
  +125.3 min:   19.89 +/- 0.07
  +169.3 min:   20.33 +/- 0.11
which fits a power law relative to the time of the burst, F_nu ~ t^-alpha,
with alpha = 1.3 +/- 0.4.

Times are relative to the GBM trigger. Magnitudes are in the Mould R
filter and in the AB system, calibrated with respect to point sources in
SDSS as described in Ofek et al. (2012, http://dx.doi.org/10.1086/664065).

There were several other optical candidates in these fields; all of the
candidates listed below are coincident with galaxies of known redshift in
SDSS, by which association we infer absolute magnitudes of M_R ~ -19,
typical of type Ia supernovae but not long GRB optical afterglows (see
Section 2.4 of Singer et al. 2015, http://arxiv.org/abs/1501.00495, and
references therein). These are:

iPTF15ha, at the coordinates:
  RA(J2000)  =  14h 03m 11.73s (210.798855 deg)
  Dec(J2000) = +64d 22' 19.3"  (+64.372029 deg)

iPTF15gu, at the coordinates:
  RA(J2000)  =  14h 29m 11.95s (217.299810 deg)
  Dec(J2000) = +56d 59' 21.4"  (+56.989264 deg)

iPTF15gy, at the coordinates:
  RA(J2000)  =  14h 47m 18.26s (221.826083 deg)
  Dec(J2000) = +54d 36' 30.6"  (+54.608492 deg)

iPTF15gx, at the coordinates:
  RA(J2000)  =  15h 03m 42.64s (225.927684 deg)
  Dec(J2000) = +54d 48' 03.1"  (+54.800849 deg)

Further observations of iPTF15gz, iPTF15hb, and iPTF15gv, are encouraged
to determine if one of the three is associated with the GRB.

The diagram http://www.its.caltech.edu/~lsinger/iptf/Fermi444908790.pdf
shows the locations of our candidates and the P48 fields in relation to
the Fermi GBM 1- and 2-sigma statistical+systematic contours.


GRB_name: GRB150206B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17417
SUBJECT: GRB 150206B: Fermi GBM detection
DATE:    15/02/06 22:30:53 GMT
FROM:    Eric Burns at U of Alabama  <eb0016@uah.edu>

E. Burns (UAH) and H.-F Yu (MPE)
report on behalf of the Fermi GBM Team:

"At 09:46:27.48 UT on 06 February 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150206B (trigger 444908790 / 150206407).

The on-ground calculated location, using the GBM trigger
data, is RA = 220.6, DEC = +57.5 (J2000 degrees,
equivalent to 14 h 42 m, 57 d 30 '), with an uncertainty
of 6.8 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 76 degrees.

Early follow-up observations of the GBM location error box by the
intermediate Palomar Transient Factory yielded three possible optical
counterparts (Singer et al. 2015, GCN 17415).

The GBM light curve consists of a single main peak
with a duration (T90) of about 5 s (50-300 keV).
The time-averaged spectrum from T0-1.024 s to T0+4.096 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.50 +/- 0.15 and
the cutoff energy, parameterized as Epeak, is 72 +/- 4 keV.

The event fluence (10-1000 keV) in this time interval is
(1.1 +/- 0.05)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.576 s in the 10-1000 keV band
is 5.2 +/- 0.3 ph/s/cm^2.

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


GRB_name: GRB150206A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17418
SUBJECT: GRB 150206A: Enhanced Swift-XRT position
DATE:    15/02/07 00:29:43 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 3576 s of XRT Photon Counting mode data and 11 UVOT
images for GRB 150206A, 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 = 10.07362, -63.18223 which is equivalent
to:

RA (J2000): 00h 40m 17.67s
Dec (J2000): -63d 10' 56.0"

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

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) 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: GRB150206A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17419
SUBJECT: GRB 150206A: GROND afterglow observations
DATE:    15/02/07 02:14:37 GMT
FROM:    Sebastian Schmidl at TLS Tautenburg  <schmidl@tls-tautenburg.de>

T. Schweyer (MPE Garching), S. Schmidl (TLS Tautenburg), and J. Greiner
(MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 150206A (Swift trigger 630019; Hagen et al.,
GCN 17413) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started at 00:32 UT on February 07, 2015, 10 hrs after the
GRB trigger. They were performed at an average seeing of 1.4" and at an
average airmass of 1.7.

We detect the optical aftergow canditate reported by Hagen et al. (GCN
17413).

Based on total exposures of 8.8 minutes in g'r'i'z' and 8.0 minutes in
JHK, at a midtime of 10.3 hrs after the burst, we measure the following
preliminary magnitudes and upper limits (all AB magnitude system):

g' = 22.6 +/- 0.2 mag,
r' = 21.9 +/- 0.1 mag,
i' = 21.2 +/- 0.1 mag,
z' = 20.8 +/- 0.1 mag,
J = 20.0 +/- 0.2 mag,
H > 20.2 mag, and
K > 19.4 mag.

The magnitudes are calibrated against GROND zeropoints and 2MASS field
stars and are not corrected for the Galactic foreground extinction
corresponding to a reddening of E_(B-V)= 0.02 in the direction of the
burst (Schlegel et al. 1998).


GRB_name: GRB150206A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17420
SUBJECT: GRB 150206A: VLT/X-shooter redshift
DATE:    15/02/07 03:55:50 GMT
FROM:    Dong Xu at DARK/NBI  <dong.dark@gmail.com>

T. Kruehler (ESO Chile), D. Xu, J. P. U. Fynbo, D. Malesani
(DARK/NBI),  Z. Cano (U. Iceland), A. de Ugarte Postigo (IAA-CSIC,
DARK/NBI)
report on behalf of a larger collaboration:

We observed the afterglow of GRB 150206A (Hagen et al. GCN 17413) with
the VLT/X-shooter spectrograph, equipped with the UVB/VIS/NIR arms and
covering the wavelength range 3000-25000 AA. In a 4x600 s spectrum we
detect absorption features of ZnII, FeII, and MgII at a common
redshift of z=2.087. The spectral trace is down to ~3760 AA, being
consistent with a Lya feature at the same redshift. We thus think this
is the redshift of the GRB.

We acknowledge excellent support from the observing staff at Paranal,
in particular Dimitri Gadotti.


GRB_name: GRB140206B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17421
SUBJECT: GRB 140206B: Continued iPTF Observations
DATE:    15/02/07 09:02:26 GMT
FROM:    Leo Singer at GSFC/iPTF  <leo.p.singer@nasa.gov>

L. P. Singer (NASA/GSFC), M. M. Kasliwal (Carnegie Observatories/Princeton),
and S. B. Cenko (NASA/GSFC) report on behalf of the intermediate Palomar
Transient Factory (iPTF) collaboration:

Using the Palomar 48-inch Oschin telescope (P48) and the robotic 60-inch
telescope (P60), we have continued observing the optical transients that
we reported (Singer et al., GCN 17415) in connection with GRB 140206B
(Burns & Yu, GCN 17417). At about 20 hours after the burst, all three of
the candidates (iPTF15gz, iPTF15hb, and iPTF15gv) are still clearly
detected in host-subtracted images, despite relatively coarse 3" seeing.
They show no statistically significant fading. We therefore dismiss them
as counterparts of the GRB.


GRB_name: GRB150202B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17422
SUBJECT: Konus-Wind observation of GRB 150202B
DATE:    15/02/07 09:29:01 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

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

The long-duration GRB 150202B
(Fermi LAT detection: Axelsson and Vianello, GCN 17385;
Fermi GBM detection: Pelassa, GCN 17388;
IPN triangulation: Hurley et al., GCN 17398)
triggered Konus-Wind at T0=86354.293 s UT (23:59:14.293).

The KW light curve shows a bright main pulse lasting about 15 s,
which is followed by a fainter second episode which
started at ~T0+100 s and lasted up to ~T0+210 s.
The emission in the main pulse is seen up to 10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150202_T86354/

As observed by Konus-Wind, the burst
had a fluence of 4.56(-0.51,+0.67)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+3.600 s,
of 1.07(-0.20,+0.20)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the main pulse
(measured from T0 to T0+12.544 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.75(-0.11,+0.14),
the high energy photon index beta = -2.39(-0.22,+0.15),
the peak energy 234(-26,+27) keV
(chi2 = 88/89 dof)

The spectrum near the maximum count rate
(measured from T0 to T0+5.888 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.69(-0.17,+0.21),
the high energy photon index beta = -2.18(-0.19,+0.12),
the peak energy 240(-38,+49) keV
(chi2 = 79/79 dof)

The time-averaged spectrum of the second episode
(measured from T0+94.464 to T0+209.152 s)
is best fit in the 20 keV - 5 MeV range
by a power law with spectral index = -1.95(-0.19,+0.21)
(chi2 = 77/78 dof).

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


GRB_name: GRB150206A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17423
SUBJECT: GRB 150206A: Swift-XRT refined Analysis
DATE:    15/02/07 10:05:20 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), J.A. Kennea (PSU), V.
Mangano (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester),
P.A. Evans (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC) and
L.M.Z. Hagen report on behalf of the Swift-XRT team:

We have analysed 8.9 ks of XRT data for GRB 150206A (Hagen et al. GCN
Circ. 17413), from 464 s to 47.9 ks after the  BAT trigger. The data
comprise 1.1 ks in Windowed Timing (WT) mode (the first 8 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. 17418).

The late-time light curve (from T0+6.4 ks) can be modelled with a
power-law decay with a decay index of alpha=2.7 (+1.0, -1.2).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.69 (+0.08, -0.07). The
best-fitting absorption column is  2.4 (+0.4, -0.3) x 10^21 cm^-2, in
excess of the Galactic value of 2.3 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.85 (+0.08, -0.07)
and a best-fitting absorption column of 9.6 (+2.1, -2.0) x 10^20 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.6 x 10^-11 (4.2 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      9.6 (+2.1, -2.0) x 10^20 cm^-2
Galactic foreground: 2.3 x 10^20 cm^-2
Excess significance: 6.0 sigma
Photon index:      1.85 (+0.08, -0.07)

If the light curve continues to decay with a power-law decay index of
2.7, the count rate at T+24 hours will be 2.2 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.0 x
10^-14 (9.4 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00630019.

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


GRB_name: GRB150206A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17424
SUBJECT: GRB 150206A: Swift/UVOT Detection
DATE:    15/02/07 10:26:33 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (IAA-CSIC/UCL-MSSL) and L. M. Z. Hagen (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150206A
483 s after the BAT trigger (Hagen et al., GCN Circ. 17413).
A source consistent with the XRT position
(Goad et al. GCN Circ. 17418)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
 RA  (J2000) =  00:40:17.63 =  10.07346 (deg.)
 Dec (J2000) = -63:10:55.7  = -63.18214 (deg.)
with an estimated uncertainty of 0.52 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: 

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

white              483          577           93         18.76 +/- 0.17
v                 2091         6690          201        >18.8
b                 2190         2912          255         19.56 +/- 0.22
u                 2165         2707           78        >19.0
w1                2140         2683           78        >18.9
w2                2414         6560          216        >19.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150203A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17425
SUBJECT: GRB 150203A iTelescope observation
DATE:    15/02/07 11:36:49 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

D. Kawamura, T. Sakamoto, A. Yoshida (AGU) 

We observed the field of GRB 150203A detected by Swift (trigger #629578; 
Ukwatta et al., GCN Circ. 17377) with the iTelescope.Net (http://www.itelescope.net) 
T11 (0.50 m Plane Wave) telescope located at the New Mexico Skies Observatory (NM, USA). 
20 images of 60 sec exposures were taken in the R filter starting from February 3 
4:22:11 (UT) about 13.3 minutes after the trigger and stopped on February 3 4:47:29 (UT).  
We do not detect the optical afterglow both in the individual images and the stacked 
image at the enhanced X-ray afterglow position (Evans et al., GCN Circ. 17378).  
The estimated five sigma upper limit of the combined image (total exposure of 1200 sec) 
is ~18.9 using the USNO-B1 catalog.


GRB_name: GRB150206A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17426
SUBJECT: GRB 150206A: Swift-BAT refined analysis
DATE:    15/02/07 20:48:22 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), L. M. Z. Hagen (PSU), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC),
T. N. Ukwatta (LANL) (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 150206A (trigger #630019)
(Hagen, et al., GCN Circ. 17413).  The BAT ground-calculated position is
RA, Dec = 10.076, -63.181 deg, which is 
   RA(J2000)  =  00h 40m 18.1s 
   Dec(J2000) = -63d 10' 50.8" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 48%.
 
The mask-weighted light curve shows a slowly rising level starting at ~T-15 sec,
with two strong clusters of peaks at ~T+85 and ~T+98 sec, and returning
to baseline at ~T+230 sec.  T90 (15-350 keV) is 83.2 +- 7.8 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-22.3 to T+164.1 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.33 +- 0.04.  The fluence in the 15-150 keV band is 1.39 +- 0.03 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+98.82 sec in the 15-150 keV band
is 10.1 +- 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/630019/BA/


GRB_name: GRB150206A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17427
SUBJECT: Konus-Wind observation of GRB 150206A
DATE:    15/02/09 11:08:41 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

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

The long-duration GRB 150206A
(Swift BAT trigger 630019: Hagen et al., GCN 17413;
Barthelmy  et al., GCN 17426;
MAXI/GSC detection: Negoro et al., GCN 17414)
triggered Konus-Wind at T0=52280.265 s UT (14:31:20.265).

The burst light curve shows a broad, multi-peaked pulse
with a total duration of ~60 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150206_T52280/

As observed by Konus-Wind, the burst
had a fluence of 5.52(-0.64,+0.69)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+4.320 s,
of 7.92(-1.78,+1.83)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+32.256 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.73(-0.14,+0.18),
the high energy photon index beta = -2.20(-0.22,+0.15),
the peak energy Ep = 228(-35,+37) keV
(chi2 = 74/97 dof)

The spectrum near the maximum count rate
(measured from T0 to T0+7.680 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.48(-0.17,+0.21),
the high energy photon index beta = -2.20(-0.22,+0.15),
the peak energy Ep = 242(-35,+38) keV
(chi2 = 84/90 dof)

Assuming the redshift z=2.087 (Kruehler et al., GCN 17420)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, and Omega_Lambda = 0.73,
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is 6.0(-0.7,+0.8)x10^53 erg,
the peak luminosity L_iso is 2.7(-0.6,+0.6)x10^53 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is 703(-109,+114) keV.

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


GRB_name: GRB150204A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17428
SUBJECT: GRB 150204A: Swift/XRT afterglow confirmation 
DATE:    15/02/09 17:26:43 GMT
FROM:    Boris Sbarufatti at INAF-OAB/IASFPA  <boris.sbarufatti@brera.inaf.it>

B. Sbarufatti (INAF-OAB/PSU) and D. Malesani (DARK/NBI) report on behalf of the Swift team

A second epoch of observations on the ground discovered GRB 150204A (Cummings, GCN 17404) was performed by Swift from T+378.9 ks to T+391.6 ks, with a 3.9 ks exposure.

The source reported by Melandri et al. (GCN 17409) has faded below detection, with a 3-sigma upper limit of 1.5E-3 counts/s (6.2e-14 erg cm^-2 s^-1).  We therefore confirm that this is the X-ray afterglow of GRB 150204A.

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


GRB_name: GRB150202B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17429
SUBJECT: GRB 150202B: Swift/XRT afterglow confirmation
DATE:    15/02/09 19:09:10 GMT
FROM:    Boris Sbarufatti at INAF-OAB/IASFPA  <boris.sbarufatti@brera.inaf.it>

B. Sbarufatti (INAF-OAB/PSU), P.A. Evans (U. Leicester) and M. H. Siegel (PSU) report on behalf of the Swift team.

Swift took a second epoch of data for the LAT/IPN GRB 150202B (Axelsson et al. GCN Circ. 17385, Hurley et al. GCN Circ. 17398) between T+515.2 ks and T+516.4 ks, with a 1.2 ks exposure time. 
Of the two unknown sources reported by Sbarufatti et al. (GCN 17405), Source #2 is still detected at a level of 8.4E-3 counts/s (3.7E-13 erg cm^-2 s^-2), comparable with the previous observation, while Source #1 has faded below detection, to a 3-sigma upper limit of 4.8E-3 counts/s (1.6E-13 erg cm^-2 s^-1).
We therefore confirm that Source #1 is the X-ray afterglow of GRB 150202B.

The results of the XRT-team automatic analysis of the likely afterglow
are at http://www.swift.ac.uk/xrt_products/TILED_GRB00039/index_1.php.
The results of the full analysis of the XRT observations are available
at http://www.swift.ac.uk/xrt_products/TILED_GRB00039/.

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


GRB_name: GRB150204A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17430
SUBJECT: GRB 150204A: GROND observations
DATE:    15/02/10 16:51:16 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann (TLS Tautenburg), K. Varela (MPE Garching), S. Schmidl (TLS
Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND
team:

We observed the field of GRB 150204A (Swift ground-analysis-detected GRB;
Cummings, GCN 17404) simultaneously in g'r'i'z'JHK with GROND (Greiner et
al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La
Silla
Observatory (Chile).

Observations started at 01:34 UT on February 05, 2015, 19 hrs after the
GRB trigger. They were performed at an average seeing of 1".0 and at an
average airmass of 1.5. We obtained a second epoch of imaging the
following night, 47 hours after the trigger, with an average seeing of
1".2 and at an average airmass of 1.2.

We detect five faint sources in the 5".0 error circle of "Source 2"
reported by Melandri et al. (GCN 17409), confirmed to be the X-ray
afterglow by Sbarufatti et al. (GCN 17428). They are located at:

Source A:
RA (J2000) = 10:40:57.43
Dec. (J2000) = -64:02:20.3

Source B:
RA (J2000) = 10:40:57.18
Dec. (J2000) = -64:02:22.7

Source C:
RA (J2000) = 10:40:56.91
Dec. (J2000) = -64:02:23.1

Source D:
RA (J2000) = 10:40:56.73
Dec. (J2000) = -64:02:21.9

Source E:
RA (J2000) = 10:40:56.38
Dec. (J2000) = -64:02:19.2

with typical errors of 0".5 in each coordinate.

None of these source vary between 20 and 48 hours after the GRB, which we
also confirm via image subtraction; therefore they are likely not
associated with the GRB. The field is crowded, and especially in the NIR,
a part of the error circle is affected by scattered light from a nearby
bright star to the east.

Based on total exposures of 125 minutes in g'r'i'z' and 100 minutes in
JHK, at a midtime of 20.3 hrs after the burst, we measure the following 3
sigma upper limits (all AB magnitude system):

g' > 23.5 mag,
r' > 23.8 mag,
i' > 23.4 mag,
z' > 23.0 mag,
J > 21.1 mag,
H > 20.9 mag,
K > 19.8 mag.

The magnitudes are calibrated against an SDSS standard star field obtained
immediately after the second-epoch observations (g'r'i'z') and 2MASS field
stars (JHK) and are not corrected for the Galactic foreground extinction
corresponding to a reddening of E_(B-V)= 0.82 mag in the direction of the
burst (Schlegel et al. 1998).


GRB_name: GRB150101B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17431
SUBJECT: GRB 150101B/ Swift J123205.1-105602: Second epoch Chandra observations
DATE:    15/02/10 18:37:00 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick), J. Hjorth (DARK/NBI), N.R. Tanvir (U. Leicester), A.J. van der Horst (GWU) report on behalf of a larger collaboration:

"We obtained a second epoch of observations of the very short GRB 150101B/ Swift J123205.1-105602 (Cummings et al. GCN 17267) with Chandra. Observations began on 10 Feb 2015, 39 days after the burst, and 32 days after the first epoch of observations (Troja et al. GCN 17289). As in the first epoch of observations a total of ~15 ks of observations were obtained with the target placed on the ACIS-S3 chip.

In these observations we clearly identify the two sources identified in previous observations. In a 1.5" aperture to avoid contamination of the sources with light from each other, we finds count rates for source SRCX1 and SRCX2 as identified by Troja et al. (GCN 17289) to be SRCX1=(35.8 +/- 1.6)e-3  and SRCX2=(1.5 +/- 0.3)e-3 respectively. This compares to SRCX1= (38.3 +/- 1.6)e-3 cps and SRCX2=(9.4 +/- 0.9)e-3 cps in the first epoch. This implies that the AGN has remained constant, and that the second source, coincident with the optical afterglow (Fong et al. GCN 17333, Levan et al. 17321) has faded by a factor of ~6.

The X-ray variability observed from source SRCX2 confirms it as the afterglow of GRB 150101B/Swift J123205.1-105602. The corresponding decay index is approximately t^-1.1, this is relatively slow for a short GRB afterglow so late after burst, and at z=0.134 (Levan et al. GCN 17281) places it in a region of parameter space much more luminous than most short bursts of comparable prompt fluence at similar times.

We thank Belinda Wilkes, Scott Wolk at the team at the Chandra X-ray Observatory for their help with these observations."


GRB_name: GRB150210A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17432
SUBJECT: GRB 150210A: Fermi GBM detection
DATE:    15/02/11 05:28:49 GMT
FROM:    Eric Burns at U of Alabama  <eb0016@uah.edu>

E. Burns (UAH) reports on behalf of the Fermi GBM Team:

"At 22:26:24.28 UT on 10 February 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150210A (trigger 445299987 / 150210935).

The on-ground calculated location, using the GBM trigger
data, is RA = 112.9, DEC = +12.4 (J2000 degrees,
equivalent to 07 h 31 m, 12 d 22 '), with an uncertainty
of 2.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 55 degrees.

The GBM light curve consists of a single main FRED-like peak
with a duration (T90) of about 31 s (50-300 keV).
The time-averaged spectrum from T0+0.002 s to T0+31.681 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.05 +/- 0.01 and
the cutoff energy, parameterized as Epeak, is 3118 +/- 216 keV.

The event fluence (10-1000 keV) in this time interval is
(1.35 +/- 0.01)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.024 s in the 10-1000 keV band
is 19.1 +/- 0.3 ph/s/cm^2.

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


GRB_name: GRB150211A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17433
SUBJECT: GRB 150211A: MASTER early optical observations
DATE:    15/02/11 12:03:20 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University, Blagoveschensk

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Yekaterinburg, Kourovka

D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory

Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

Claudio Mallamaci, Carlos Lopez and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)



MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Tunka was pointed to the  GRB150211A 39 sec after notice time 
and 55 sec after trigger time at 2015-02-11 11:53:08 UT in two 
polarizations. On our first (10s exposure)  set we haven't found optical transient  within SWIFT error-box 
(ra=16 59 25 dec=+55 22 58 r=0.050000).
The 5-sigma upper limit has been about 15.5 mag
The position hava a high (z~75d) zenith distance.
The observation and data reductions is continued.
The message may be cited.


GRB_name: GRB150211A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17434
SUBJECT: GRB 150211A: Swift detection of a burst
DATE:    15/02/11 12:09:47 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

R. L. C. Starling (U Leicester), S. D. Barthelmy (GSFC),
M. M. Chester (PSU), P. A. Evans (U Leicester),
N. Gehrels (NASA/GSFC), J. A. Kennea (PSU) and
K. L. Page (U Leicester) report on behalf of the Swift Team:

At 11:52:11 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150211A (trigger=630714).  Swift did not slew because of observing
constraint.  The BAT on-board calculated location is 
RA, Dec 254.856, +55.383, which is 
   RA(J2000)  =  16h 59m 25s
   Dec(J2000) = +55d 22' 59"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows several overlapping peaks
structure with a total duration of about 20 sec.  The peak count rate
was ~7000 counts/sec (15-350 keV), at ~4 sec after the trigger. 

Due to an observing constraint, Swift will not slew until T0+33.7
minutes. There will be no XRT or UVOT data until this time. 

The star tracker lost lock about 1 minute before the trigger,
but the location should be good by propagating the gyros.  INTEGRAL-SPIACS
also saw this burst. 

Burst Advocate for this burst is R. L. C. Starling (rlcs1 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB150211A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17435
SUBJECT: GRB 150211A: Swift-XRT observations
DATE:    15/02/11 12:54:45 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

S. Campana (INAF-OAB), P.A. Evans (U. Leicester), J.P. Osborne (U.
Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU) and G. Tagliaferri
(INAF-OAB) report on behalf of the Swift-XRT team:

The XRT began observing the field of GRB 150211A at 12:27:22.5 UT,
2111.0 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source located at RA, Dec 254.85863,
55.39235 which is equivalent to:
   RA(J2000)  = 16h 59m 26.07s
   Dec(J2000) = +55d 23' 32.5"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 34 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 (1.61 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 5.1
(+2.58/-2.25) x 10^21 cm^-2 (90% confidence). 


GRB_name: GRB150211A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17436
SUBJECT: GRB 150211A: No afterglow detection in the Swift/UVOT initial observation
DATE:    15/02/11 13:04:55 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

M. M. Chester (Penn State) and R. L. C. Starling (U. Leicester) report on 
behalf of the Swift/UVOT team:

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 2115 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 0.02.


GRB_name: GRB150211A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17437
SUBJECT: GRB 150211A: RATIR Optical and NIR Observations
DATE:    15/02/11 13:41:02 GMT
FROM:    Owen Littlejohns at Az State U  <olittlej@asu.edu>

Owen Littlejohns (ASU), Nat Butler (ASU), Alan M. Watson (UNAM),
Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer
(UNAM), Chris Klein (UCB), Ori Fox (UCB), J. Xavier Prochaska
(UCSC), Josh Bloom (UCB), Antonino Cucchiara (ORAU/GSFC), Eleonora
Troja (GSFC), Enrico Ramirez-Ruiz (UCSC), JosÃ© A. de Diego (UNAM),
Leonid Georgiev (UNAM), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga
(UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report:

We observed the field of GRB 150211A (Starling, et al., GCN 17434)
with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org) on the 1.5m Harold Johnson Telescope at the
Observatorio AstronÃ³mico Nacional on Sierra San Pedro MÃ¡rtir from
2015/02 11.50 to 2015/02 11.53 UTC (0.05 to 1.29 hours after the
BAT trigger), obtaining a total of 1.07 hours exposure in the r, i
and z bands.

For a source within the Swift-XRT error circle (Campana, et al.,
GCN 17435), in comparison with USNO-B1 and 2MASS, we obtain the
following upper limits (3-sigma):

  r     > 23.34
  i     > 23.71
  z     > 20.21

These magnitudes are in the AB system and are not corrected for
Galactic extinction in the direction of the GRB. These upper
limits are consistent with observations by the Swift-UVOT (Chester,
et al, GCN 17436) and MASTER II robotic telescope (Ivanov, et al,
GCN 17433).

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB150210A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17438
SUBJECT: GRB 150210A: Fermi-LAT detection
DATE:    15/02/11 14:16:23 GMT
FROM:    Sylvia J. Zhu at NASA/GSFC/UMD  <sjzhu@umd.edu>

S. Zhu (UMD), E. Bissaldi (INFN Bari), J. Racusin (NASA/GSFC),
E. Sonbas (Adiyaman Univ.), D. Kocevski (NASA/GSFC),
M. Yassine (LUPM) report on behalf of the Fermi-LAT team:

At 22:26:24.28 UT on 10 February 2015, Fermi-LAT detected
high-energy emission from GRB 150210A,
which was also detected by Fermi-GBM (trigger 445299987 / 150210935)
(Burns, GCN 17432).

The best LAT on-ground location is found to be

RA, Dec = (112.15, 13.27) (J2000)

with an error radius of 0.33 deg (90% containment, statistical error only).
This position was 55 deg from the LAT boresight at the time of the trigger
and is consistent with the GBM position. It remained in the
LAT field of view for about 1000 seconds after trigger, and reentered
the field of view at T0+5000 seconds.

The data from the Fermi-LAT show a significant increase
in the event rate within 10 degrees of the GBM location after the
GBM trigger that is spatially and temporally correlated
with the GBM emission with high significance.
More than 20 photons above 100 MeV are observed in the first 100
seconds, of which ~15 photons are coincident with the GBM peak.
The highest-energy photon is a  ~1 GeV event which is observed
2 seconds after the GBM trigger. Using the LAT Low Energy (LLE)
data selection, an increase in the event rate at > 20 sigma significance
above background was observed approximately coincident with the
time of the GBM emission.

A Swift ToO has been requested for this burst.

The Fermi-LAT point of contact for this burst is Sylvia Zhu
(sjzhu@umd.edu).


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.


GRB_name: GRB150210A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17439
SUBJECT: IPN Triangulation of GRB 150210A
DATE:    15/02/11 14:58:52 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

K. Hurley, on behalf of the IPN,

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team, and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
report:

The long-duration, bright GRB 150210A has been detected by Fermi (GBM: 
Burns, GCN Circ. 17432; LAT: Zhu et al., GCN Circ. 17438), Konus-Wind, 
and INTEGRAL (SPI-ACS), so far, at about 80784 s UT (22:26:24).

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   111.853 (07h 27m 25s) +13.832 (+13d 49' 54")
  Corners:
   111.458 (07h 25m 50s) +11.396 (+11d 23' 45")
   111.572 (07h 26m 17s) +16.337 (+16d 20' 13")
   112.332 (07h 29m 20s) +16.259 (+16d 15' 31")
   112.206 (07h 28m 49s) +11.314 (+11d 18' 52")
  ---------------------------------------------
The error box area is 3.6 sq. deg, and its maximum
dimension is 5.1 deg (the minimum one is 44 arcmin).
The Sun distance was 148 deg.

The LAT (statistical-only) error circle (GCN 17438) overlaps the box. 
The distance between the center of the LAT position and the center of 
the error box is 0.63 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB150210_T80787/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming 
GCN Circular.


GRB_name: GRB150210A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17440
SUBJECT: Konus-Wind observation of GRB 150210A
DATE:    15/02/11 15:04:47 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long-duration, hard-spectrum GRB 150210A
(Fermi-GBM detection: Burns, GCN 17432;
Fermi-LAT detection: Zhu et al., GCN 17438;
IPN triangulation: Golenetskii et al., GCN 17439)
triggered Konus-Wind at T0=80787.209 s UT (22:26:27.209).

The light curve shows a bright, multi-peaked pulse with a duration
of ~3.5 s followed by a much weaker tail visible up to ~T0+30 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150210_T80787/

As observed by Konus-Wind, the burst had a fluence
of 7.8(-0.8,+0.9)x10^-5 erg/cm2, and a 64-ms peak flux,
measured from T0+2.368 s, of 4.2(-0.3,+0.3)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+24.832 s)
is best fit in the 20 keV - 15 MeV range
by the cutoff power law with the following model parameters:
the photon index alpha = -0.99(-0.07,+0.08),
and the peak energy Ep = 2170(-340,+440) keV,
chi2 = 107/98 dof.
Fitting this spectrum with the Band model yields the same
values of alpha and Ep with an upper limit on the high-energy
photon index beta of -2.6

The spectrum near the peak count rate (measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 15 MeV range
by the cutoff power law with the following model parameters:
the photon index alpha = -0.89(-0.06,+0.06),
and the peak energy Ep = 2250(-240,+280) keV,
chi2 = 126/98 dof.

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


GRB_name: GRB150210A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17441
SUBJECT: GRB 150210A: Tiled Swift observations
DATE:    15/02/11 17:01:24 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
Fermi/LAT GRB 150210A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00040

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the Fermi/LAT event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

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


GRB_name: GRB150211A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17442
SUBJECT: GRB 150211A: Swift-XRT refined Analysis
DATE:    15/02/11 17:05:56 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R. L. C. Starling (U Leicester) reports on behalf of the Swift-XRT
team:

We have analysed 837 s of XRT data for GRB 150211A (Starling et al. GCN
Circ. 17434), from 2.1 ks to 3.0 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The refined XRT position is
RA, Dec = 254.8581, +55.3927 which is equivalent to:

RA (J2000): 16 59 25.94
Dec(J2000): +55 23 33.5

with an uncertainty of 3.6 arcsec (radius, 90% confidence).

The light curve can be modelled with a power-law decay with a decay
index of alpha=1.0 (+/-0.9).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.83 (+0.21, -0.20). The
best-fitting absorption column is  6.2 (+1.6, -1.4) x 10^21 cm^-2, in
excess of the Galactic value of 1.6 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.7 x 10^-11 (7.2 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      6.2 (+1.6, -1.4) x 10^21 cm^-2
Galactic foreground: 1.6 x 10^20 cm^-2
Excess significance: 7.1 sigma
Photon index:      1.83 (+0.21, -0.20)

If the light curve continues to decay with a power-law decay index of
1.0, the count rate at T+24 hours will be 0.029 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.4 x
10^-12 (2.1 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/00630714.

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


GRB_name: GRB150211A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17443
SUBJECT: GRB 150211A: Mondy optical upper limit
DATE:    15/02/11 19:32:58 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), A. Volnova (IKI), E. Klunko (ISTP), I. Korobtsev 
(ISTP), M. Eselevich (ISTP), A. Pozanenko (IKI) report on behalf of 
larger GRB follow-up collaboration:

We observed the field of GRB 150211A (Starling, et al., GCN 17434) with 
AZT-33IK telescope of Sayan observatory (Mondy). We obtained several 
images in R-filter on Feb., 11,  starting (UT) 12:02:35. Within XRT 
error cirvle (Campana, et al.,GCN 17435)  we do not detect any optical 
source. Upper limit is following

Date       UT start   t-T0     Filter   Exp.  UL(3sigma)
                       (mid, days)       (s)

2015-02-11 12:02:35   0.03091  R       1800   21.9


The photometry   is based on nearby USNO-B1.0 stars:
USNO-B1.0_id     R2
1453-0255559    18.45
1453-0255560    18.27
1453-0255536    18.49


GRB_name: GRB150211A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17444
SUBJECT: GRB 150211A: KAIT Optical Upper Limit
DATE:    15/02/11 19:46:58 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 150211A (Starling al.,
GCN 17434) starting at 11:54:12 UT, 121 s after the burst.
Observations were performed with an automatic sequence in the
clear (roughly R), V, and I filters, and the exposure time was
20 s per image. We do not detect any new source in our
images within the refined XRT error circle (Starling et al.,
GCN 17442). The typical limiting magnitude of our single clear
image is about 18.0 calibrated to USNO B1.0.


GRB_name: GRB150211A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17445
SUBJECT: GRB 150211A: Swift-BAT refined analysis
DATE:    15/02/11 20:35:19 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), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), R. L. C. Starling (U Leicester), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(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 150211A (trigger #630714)
(Starling, et al., GCN Circ. 17434).  The BAT ground-calculated position is
RA, Dec = 254.846, 55.390 deg, which is 
   RA(J2000)  =  16h 59m 23.0s 
   Dec(J2000) = +55d 23' 23.2" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 16%.
 
The mask-weighted light curve shows several overlapping peaks starting
at ~T-10 sec, peaking at ~T+5 sec, and ending at ~T+30 sec.
T90 (15-350 keV) is 13.6 +- 2.0 sec (estimated error including systematics).
 
The time-averaged spectrum from T-11.24 to T+9.18 sec is best fit
by a Double Blackbody.  This fit gives a kT1 = 7.99 +2.8/-2.1 keV,
kT2 = 24.7 +7.5/-3.2 keV, and (R1/D10)^2 = 6.0 +9.1/-3.3 and
R2/D10)^2 = 0.22 +0.11/-0.15.  (chi squared 74.8 for 59 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 9.9 +- 1.2 x 10^-7 erg/cm2
and the 1-sec peak flux measured from T+4.36 sec in the 15-150 keV band is
12 +- 1 ph/cm2/sec.  A Cutoff PL has an Epeak of 123.4 +- 27.5 keV
(chi squared 81.8 for 56 d.o.f.).  And for completeness, the fit to a
simple power law gives a photon index of 1.28 +- 0.05
(chi squared 107 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/630714/BA/


GRB_name: GRB150210A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17446
SUBJECT: GRB 150210A: MASTER SN detection during LAT error box inspection
DATE:    15/02/11 21:09:24 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

O. Gres ,K.Ivanov, S.Yazev, N.M.Budnev, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University

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

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University, Blagoveschensk

K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University

V.Krushinski, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory


Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

Claudio Mallamaci, Carlos Lopez and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)



MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Kislovodsk was pointed to the  GRB150210A 22 sec after notice 
time and 1364 sec after trigger time at 2015-02-10 22:49:09 UT by FERMI 
GBM coordinates  (ra=07 31 23 dec=+12 21 33 r=2.200000) (Burns et. al . 
GCN 17432). We cover a 70% part of FERMI LAT (Zhu et al. GCN 17438) error 
box with upper limit 17.5

MASTER II  robotic telescope  located in Tunka was pointed to the 
GRB150210A 3444 sec after  the LAT notice time and 60443 sec after trigger 
time at 2015-02-11 15:13:47 UT.

During LAT error box inspectoion MASTER-Tunka auto-detection system 
discovered OT source at (RA, Dec) = 07h 29m 40.10s +14d 14m 25.5s on 
2015-02-11.64502 UT (Gres et al. ATel 17446).

The OT unfiltered magnitude is 17.4m (the limit is 20.0m). OT is located 
at a distance 0.2W 2.8N from a center on unknown galaxy.
It seems that this supernova was found by chance during the LAT error box 
inspection.
OT image available here 
http://master.sai.msu.ru/static/OT/MASTERJ072940.10+141425.5.jpg
The OT is seen in 31 images. There is no minor planet at this place.
We have reference image without OT on 2012-02-18.58510 UT with unfiltered 
magnitude limit 19.8m.

The message may be cited.


GRB_name: GRB150211A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17447
SUBJECT: GRB 150211A: Swift/UVOT Upper Limits
DATE:    15/02/12 02:35:34 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

M. M. Chester (Penn State) and R. L. C. Starling (U Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150211A
2116 s after the BAT trigger (Starling et al., GCN Circ. 17434).
No optical afterglow consistent with the XRT position (Starling 
GCN Circ. 17442) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC          2116         2266          147         >21.3
white             2116         3123          383         >21.8
v                 2272         8220          255         >20.4
b                 2371         2918          236         >20.1
u                 2346         2713           58         >19.7
w1                2321         2688           58         >19.4
m2                8225         8421          193         >20.4
w2                3129         3243          112         >19.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150211A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17448
SUBJECT: GRB 150211A iTelescope observation
DATE:    15/02/12 07:54:47 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

D. Kawamura, T. Sakamoto, A. Yoshida (AGU) 

We observed the field of GRB 150211A detected by Swift (trigger #630714; 
Starling et al., GCN Circ. 17434) with the iTelescope.Net (http://www.itelescope.net) 
T11 (0.50 m Plane Wave) telescope located at the New Mexico Skies Observatory (NM, USA).  
20 images of 60 sec exposures were taken in the R filter starting from February 11 12:06:11 (UT) 
about 14.3 minutes after the trigger and stopped on February 11 12:32:17 (UT).  
We do not detect the optical afterglow both in the individual images and the stacked image 
at the enhanced X-ray afterglow position (Starling et al., GCN Circ. 17442).  The estimated 
five sigma upper limit of the combined image (total exposure of 1200 sec) is ~19.1 using 
the USNO-B1 catalog.


GRB_name: GRB150212A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17449
SUBJECT: GRB 150212A: Swift detection of a burst
DATE:    15/02/12 11:19:00 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

K. L. Page (U Leicester), A. Amaral-Rogers (U Leicester),
S. D. Barthelmy (GSFC), M. M. Chester (PSU),
P. A. Evans (U Leicester), F. E. Marshall (NASA/GSFC),
C. J. Mountford (U Leicester) and P. T. O'Brien (U Leicester) report
on behalf of the Swift Team:

At 10:57:19 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150212A (trigger=630876).  The Swift slew was delayed by 4.7 min
due to an observing constraint.  The BAT on-board calculated location is 
RA, Dec 285.521, +47.407 which is 
   RA(J2000)  =  19h 02m 05s
   Dec(J2000) = +47d 24' 27"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single FRED peak
with a duration of about 10 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to an observing constraint, Swift did not slew until T0+4.7
minutes. By this time Swift had entered the South Atlantic Anomaly,
from which it will emerge at 11:26 UT. There will be no XRT or UVOT
data until this time. 

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


GRB_name: GRB150211A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17450
SUBJECT: Konus-Wind observation of GRB 150211A
DATE:    15/02/12 11:45:42 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long-duration GRB 150211A (Swift-BAT trigger #630714:
Starling et al., GCN 17434)
triggered Konus-Wind at T0=42728.740 s UT (11:52:08.740).

The KW light curve shows a single multi-peaked emission episode
with a duration of ~13 s.
The emission is visible up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB150211_T42728/

As observed by Konus-Wind, the burst had a fluence
of 2.4(-0.3,+0.3)x10^-5 erg/cm2, and a 64-ms peak flux,
measured from T0+7.808 s, of 5.6(-0.7,+0.7)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+16.128 s)
is best fit in the 20 keV - 15 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.62 (-0.20,+0.25),
the high energy photon index beta = -2.07 (-0.15,+0.10),
the peak energy Ep = 145 (-24,+30) keV,
chi2 = 114/97 dof.

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


GRB_name: GRB150212A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17451
SUBJECT: GRB150212A: P60 Afterglow Candidate
DATE:    15/02/12 11:47:36 GMT
FROM:    S. Bradley Cenko at NASA/GSFC  <brad.cenko@nasa.gov>

S. B. Cenko (NASA/GSFC) reports on behalf of a larger collaboration:

We have imaged the field of the Swift GRB150212A (Page et al., GCN 17449) with the robotic Palomar 60 inch telescope.  Observations were obtained in the Sloan riz filters beginning at 11:12 UT (~ 15 min after the Swift trigger).  We identify a bright source in the BAT error circle not present in archival DSS imaging of the field in all 3 filters:

   RA: 19:01:53.92
   Dec: +47:26:10.7

We measure a preliminary magnitude of r = 16.8 at ~ 15 min after the Swift trigger (calibration performed with respect to nearby point sources from the APASS catalog).  While we have not yet confirmed fading, we consider this source to be the likely optical afterglow of GRB150212A.


GRB_name: GRB150212A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17452
SUBJECT: GRB 150212A: Swift-XRT afterglow detection
DATE:    15/02/12 11:58:35 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

The XRT began observing the field at 11:03:12.7 UT, 353.7 seconds after
the BAT trigger. Due to passage of the spacecraft through the South 
Atlantic Anomaly, no XRT data were collected until T0+1805 s.

Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 285.48092, 47.36602 which is equivalent
to:
    RA(J2000)  = 19h 01m 55.42s
    Dec(J2000) = +47d 21' 57.7"
with an uncertainty of 4.3 arcseconds (radius, 90% containment). This
location is 176 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 5.20
x 10^20 cm^-2 (Willingale et al. 2013).

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


GRB_name: GRB150210A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17453
SUBJECT: GRB 150210A: Swift-XRT observations
DATE:    15/02/12 12:12:53 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

V. Mangano (PSU), M.C. Stroh (PSU), B.P. Gompertz (U. Leicester), J.P.
Osborne (U. Leicester), V. D'Elia (ASDC), M. de Pasquale (INAF-IASFPA),
A. Maselli  (INAF-IASFPA), D.N. Burrows (PSU) and P.A. Evans (U.
Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 150210A (Zhu et al. GCN Circ. 17438) in a
series of observations tiled on the sky. The total exposure time is 7.3
ks, distributed over 4 tiles; the maximum exposure at a single sky
location was 4.3 ks. The data were collected between T0+66.9 ks and
T0+95.4 ks, and are entirely in Photon Counting (PC) mode. 

No uncatalogued X-ray sources have been detected. The 3-sigma upper
limit in the field (not including the regions where the tiles overlap)
ranges from ~0.004 to ~0.008 ct s^-1, corresponding to a 0.3-10 keV
observed flux of 1.5e-13 to 3.3e-13 erg cm^-2 s^-1 (assuming a typical
GRB spectrum).

A previously-catalogued X-ray source has been detected, however because
it is a catalogued object it is unlikely to be the afterglow.

The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at http://www.swift.ac.uk/xrt_products/TILED_GRB00040.

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


GRB_name: GRB150212A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17454
SUBJECT: GRB 150212A: P60 Afterglow Retraction
DATE:    15/02/12 12:22:19 GMT
FROM:    S. Bradley Cenko at NASA/GSFC  <brad.cenko@nasa.gov>

S. B. Cenko (NASA/GSFC) reports on behalf of a larger collaboration:

We have obtained further imaging of the field the Swift GRB 150212A (Page et al., 17449) with the robotic Palomar 60 inch telescope.  The candidate afterglow we previously identified (GCN 17451) has remained at a constant brightness over the course of the last hour, and is well offset from the candidate XRT afterglow (Evans et al., GCN 17452).  Further inspection of archival catalogs indicates this object is likely to be a high proper motion star.  We apologize for any inconvenience this may have caused.


GRB_name: GRB150212A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17455
SUBJECT: GRB 150212A:  No Swift/UVOT detection in initial observation 
DATE:    15/02/12 12:30:39 GMT
FROM:    Margaret Chester at PSU  <chester@swift.psu.edu>

M. M. Chester (Penn State), K. L. Page (U Leicester), and A. Amaral-Rogers 
(U Leicester) report on behalf of the Swift/UVOT team:


UVOT took a finding chart exposure of 150 seconds with the White filter
starting 1811 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 0.06.


GRB_name: GRB150212A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17456
SUBJECT: GRB 150212A: MASTER optical observations
DATE:    15/02/12 13:22:42 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University, Blagoveschensk

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

V.Krushinsky, I.Zalozhnih,  A. Popov
Ural Federal University, Yekaterinburg, Kourovka

D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory

Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

Claudio Mallamaci, Carlos Lopez and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)



MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Tunka was pointed to the  GRB150212A (Page et. al. GCN 17449) 
32 sec after notice time and 47 sec after trigger time at 2015-02-12 
10:58:06 UT in two polarization. Unfortunately we were unable to obtain 
satisfactory data on the first images due to clouds and high zenith 
distance (z~75 d).

In the process of further observations we do not see the optical transient 
and obtained the following upper limits:

T_start   T-Tmid Expt.   Mlimit
11:08:50  761     140      11.5
11:11:52  958     170      11.5
11:15:26  1177    180      12.5
11:26:34  1845    180     12.6
11:32:12  2183    180      15.0
11:32:12  3447   1800      16.7
11:35:58  2641    540      16.1

So weak upper limits associated with the observation through clouds and 
large zenith distance of the object.


GRB_name: GRB150212A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17457
SUBJECT: GRB 150212A: Swift-BAT refined analysis
DATE:    15/02/12 14:28:38 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), A. Amaral-Rogers (U Leicester), S. D. Barthelmy (GSFC), 
W. H. Baumgartner (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 150212A (trigger #630876)
(Page, et al., GCN Circ. 17449).  The BAT ground-calculated position is
RA, Dec = 285.497, 47.389 deg, which is 
   RA(J2000)  =  19h 01m 59.2s 
   Dec(J2000) = +47d 23' 19.1" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 71%.
 
The mask-weighted light curve is FRED peak starting at ~T-1 sec, peaking
at ~T+1 sec, and ending at ~T+25 sec.  T90 (15-350 keV) is 11.4 +- 4.1 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-0.20 to T+19.66 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.50 +- 0.11.  The fluence in the 15-150 keV band is 8.9 +- 0.6 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.82 sec in the 15-150 keV band
is 1.9 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/630876/BA/


GRB_name: GRB150212A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17458
SUBJECT: GRB 150212A: Skynet DSO14/GORT observations
DATE:    15/02/12 20:27:47 GMT
FROM:    Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet  <atrotter@physics.unc.edu>

A. Trotter, D. Reichart, A. LaCluyze, J. Haislip, A. Smith, D. Caton, L. Hawkins, K. McLin, L. Cominsky, A. Aji, T. Berger, A. Dow, A. Foster, N. Frank, K. Ivarsen, M. Maples, J. Moore, M. Nysewander, C. Salemi, and J. A. Crain report:

Skynet observed the Swift BAT/XRT localization of GRB 150212A (Page et al., GCN 17449, Swift trigger=630876) with the 14" telescope at the Appalachian State University Dark Sky Observatory (DSO14) in NC, USA, and with the 14" GLAST Optical Robotic Telescope (GORT) at the Hume Observatory in CA, USA. DSO14 obtained exposures of the field starting at 2015-02-12 10:58:05 (t=46s post-trigger); GORT was delayed until 48m post-trigger due to clouds. Skynet took a total of 29 exposures ranging from 5s to 160s in the R and I bands. We do not detect any optical source at the XRT afterglow position reported by Evans (GCN 17452).

Our early-time DSO14 limiting magnitudes are:
==============================================
tmid    scope   band    exposures   lim mag
----------------------------------------------
48s     DSO14    I      1 x 5s      >15.2
102s    DSO14    I      2 x 10s     >16.4
108s    DSO14    R      1 x 5s      >16.0
==============================================

Stacked subsets of those images that maximize the S/N ratio give limiting magnitudes:
==============================================
tmid    scope   band    exposures   lim mag
----------------------------------------------
15.4m   DSO14    R      1 x 80s      >18.4
                        1 x 160s
16.1m   DSO14    I      1 x 80s      >18.4
                        1 x 160s                       
74m     GORT     R      4 x 160s     >17.2
84m     GORT     I      3 x 160s     >16.8
==============================================

Magnitudes are in the Vega System, calibrated to 10 APASS stars in the field.  Magnitudes have not been corrected for line-of-sight Milky Way dust extinction, with expected E(B-V)=0.051 (Schlafly & Finkbeiner 2011).

No further Skynet observations are scheduled.


GRB_name: GRB150212A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17459
SUBJECT: GRB 150212A: Khureltogot optical upper limit
DATE:    15/02/12 20:37:01 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), S. Schmalz (AIP), N. Tungalag (Research Center of 
Astronomy and Geophysics MAS), A. Volnova (IKI), I.Molotov (KIAM), A. 
Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of 150212A (Page et al., GCN 17449) with ORI-40 
telescope of Khureltogot observatory on Feb., 12 starting on (UT) 
11:32:28. We obtained 24 unfiltered images of 15 s exposure. We did not 
detect any optical counterpart in XRT error circle (Evans et al. GCN 
17452). Details of the photometry are following:

Date        UT start  t-T0    Filter Exp.  uplim (3 sigma)
                       (mid, days) (s)

2015-02-12  11:32:28  0.02739 none  24*15  15.8

The star mentioned by Cenko et al. (GCNs 17451, 17454) is visible in our 
combined image and have a brightness of 15.85 +/- 0.25.

The photometry is based on R magnitudes of nearby USNO-B1.0 stars

USNO-B1_id    R2
1374-0373548  15.39
1374-0373502  14.41


GRB_name: GRB150212A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17460
SUBJECT: GRB 150212A: RATIR Optical and NIR Observations
DATE:    15/02/12 22:41:55 GMT
FROM:    Nat Butler at Az State U  <natbutler@asu.edu>

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), Jos A. de Diego (UNAM), Leonid Georgiev (UNAM), Jess
Gonzlez (UNAM), Carlos Romn-Ziga (UNAM), Neil Gehrels (GSFC), and
Harvey Moseley (GSFC) report:

We observed the field of GRB 150212A (Page, et al., GCN 17449) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronmico Nacional on
Sierra San Pedro Mrtir from 2015/02 12.51 to 2015/02 12.55 UTC (1.29 to
2.31 hours after the BAT trigger), obtaining a total of 0.89 hours exposure
in the r, i, and z bands.

We find one uncatalogued source within the Swift XRT error circle (Evans,
et al., GCN 17452) at a position RA, Dec = 285.48273,  47.36637 (+/- 0.5",
J2000) with magnitudes r = 23.1 +/- 0.4 and i = 21.4 +/- 0.1.  This source
does not appear to fade in time during our observation.  For other
potential sources within the XRT error circle, in comparison with USNO-B1
and 2MASS, we obtain the following upper limits (3-sigma):

  r > 23.1
  i > 23.3
  z > 19.6

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio Astronmico Nacional in San Pedro
Mrtir.


GRB_name: GRB150211A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17461
SUBJECT: GRB 150211A: ROTSE-III Upper Optical Limit
DATE:    15/02/12 22:49:20 GMT
FROM:    Farley V. Ferrante at Southern Methodist U/ROTSE  <fferrante@smu.edu>

F. V. Ferrante (SMU), T. Guver (Istanbul U), G. Dhungana (SMU), R. Staten (SMU)

and R. Kehoe (SMU) report on behalf of the ROTSE GRB team:

The 0.45-m ROTSE-IIIb telescope, located at McDonald Observatory, Texas,

responded to GRB 150211A (Swift trigger 630714; Starling, et al.,GCN 17434) with

imaging beginning 3.8 s after the GCN notice time. An automated response recorded

the first image at 11:52:43.8 UT, 30.7 s after the burst, under fair observing conditions.

The unfiltered images are calibrated relative to USNO A2.0 (R). We do not detect an

optical source within the refined Swift-XRT error circle (Starling et al., GCN 17442).

We set the following upper limit:


start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
-----------------------------------------------------------------------------------------------
11:52:43.8   11:53:43.8      60       17.6           30.7               N


GRB_name: GRB150212A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17462
SUBJECT: GRB 150212A: Swift-XRT refined Analysis
DATE:    15/02/13 08:30:07 GMT
FROM:    Alex Amaral-Rogers at U.of Leicester  <aar14@leicester.ac.uk>

A. Amaral-Rogers (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page
(U. Leicester), M. de Pasquale (INAF-IASFPA), A. Maselli 
(INAF-IASFPA), A. Melandri (INAF-OAB), D.N. Burrows (PSU), J.A. Kennea
(PSU) and K. L. Page (U Leicester) report on behalf of the Swift-XRT
team:

We have analysed 4.1 ks of XRT data for GRB 150212A (Page et al. GCN
Circ. 17449), from 1.8 ks to 54.6 ks after the BAT trigger. The data
are entirely in Photon Counting (PC) mode. The refined XRT position is
RA, Dec = 285.4799, +47.3656 which is equivalent to:

RA (J2000): 19 01 55.16
Dec(J2000): +47 21 56.3

with an uncertainty of 3.7 arcsec (radius, 90% confidence).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.56 (+0.15, -0.14).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.3 (+/-0.4). The
best-fitting absorption column is  1.7 (+1.2, -1.0) x 10^21 cm^-2, in
excess of the Galactic value of 5.2 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.0 x 10^-11 (4.4 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.7 (+1.2, -1.0) x 10^21 cm^-2
Galactic foreground: 5.2 x 10^20 cm^-2
Excess significance: 2.0 sigma
Photon index:      2.3 (+/-0.4)

If the light curve continues to decay with a power-law decay index of
0.56, the count rate at T+24 hours will be 0.012 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.5 x
10^-13 (5.2 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/00630876.

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


GRB_name: GRB150213A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17463
SUBJECT: GRB 150213A: Fermi GBM detection
DATE:    15/02/13 16:09:01 GMT
FROM:    Binbin Zhang at UAH  <binbin.zhang@uah.edu>

Bin-Bin Zhang (UAH) reports on behalf of the Fermi GBM Team:

"At 00:01:48.70 UT on 13 February 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150213A (trigger 445478511 / 150213001).

The on-ground calculated location, using the GBM trigger data, is RA = 95.29,
DEC = -4.85 (J2000 degrees), with an uncertainty of 1.0 degrees (radius,
1-sigma containment,statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees). This trigger
resulted in an Autonomous Repoint Request (ARR) that was accepted and the
spacecraft slewed to the GBM in-flight location. The angle from the Fermi
LAT boresight at trigger time is 77 degrees.


The GBM light curve consists of a single main FRED-like peak
with a duration (T90) of about 4.1 s (50-300 keV).

The time-averaged spectrum from T0+0.5 s to T0+4.6 s is
best fit by a a Band function with Epeak = 57.8 +/- 0.6 keV,
alpha = -1.1+/- 0.02, and beta = -2.6 +/- 0.03. The event fluence
(10-1000 keV) in this time interval is (2.78 +/- 0.02)E-05 erg/cm^2.
The 1-sec peak photon flux measured starting from T0+1.76 s in the
10-1000 keV band is 189.0 +/- 1.1 ph/s/cm^2.

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


GRB_name: GRB150213B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17464
SUBJECT: GRB 150213B: Swift detection of a burst with an optical afterglow
DATE:    15/02/13 22:47:24 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

C. Pagani (U Leicester), S. D. Barthelmy (GSFC),
N. Gehrels (NASA/GSFC), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL),
F. E. Marshall (NASA/GSFC), C. J. Mountford (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL) and
B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:

At 22:31:30 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150213B (trigger=631051).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 253.425, +34.179 which is 
   RA(J2000)  =  16h 53m 42s
   Dec(J2000) = +34d 10' 43"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty). As is typical for image triggers (64 sec),
the realtime TDRSS light curve does not show anything significant. 

The XRT began observing the field at 22:33:54.1 UT, 143.3 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 253.4532, 34.1886 which is equivalent to:
   RA(J2000)  = +16h 53m 48.77s
   Dec(J2000) = +34d 11' 19.0"
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This
location is 90 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 2.84e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 152 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 16:53:48.65 = 253.45271
  DEC(J2000) = +34:11:19.4  =  34.18872
with a 90%-confidence error radius of about 0.63 arc sec. This position is 1.5
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.46 with a 1-sigma error of about  0.15. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02. 

Burst Advocate for this burst is C. Pagani (cp232 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB150213B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17465
SUBJECT: GRB 150213B: Tautenburg Afterglow Detection
DATE:    15/02/14 01:22:21 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, B. Stecklum, and F. Ludwig (TLS Tautenburg) report:

We began observations of GRB 150213B (Swift trigger 631051, Pagani et al.,
GCN 17464) with the 1.34m Tautenburg Schmidt telescope about 80 min after
the GRB, at airmass 2.9.

At the UVOT position given by Pagani et al., we detect the optical
afterglow in multiple Rc band exposures of 600 sec exposure time each. Due
to the PSF wings of a nearby bright star, no magnitude can be determined
at this time, but the source has clearly faded compared to the early Swift
detection.

Observations are ongoing.


GRB_name: GRB150212A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17466
SUBJECT: GRB 150212A: Swift/UVOT Observations
DATE:    15/02/14 01:30:43 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel@swift.psu.edu>

M. H. Siegel, M. M. Chester (PSU), A. Amaral-Rogers (U Leicester)
and D. Malesani (DARK/NBI) report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150212A
1812 s after the BAT trigger (Page et al. GCN Circ. 17449; Chester et al.
GCN Circ. 17455).  A cataloged optical source is detected
within the XRT error circle (Evans GCN Circ. 17452).  The measured
magnitudes are consistent with the cataloged values and no fading is
evident.


GRB_name: GRB150213B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17467
SUBJECT: GRB 150213B: optical detection from the NOT
DATE:    15/02/14 06:11:29 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

D. Malesani (DARK/NBI), D. Xu (DARK/NBI), A. de Ugarte Postigo (IAA/CSIC and DARK/NBI), P. 
Jakobsson (Univ. Iceland), and J. Telting (NOT) report on behalf of a 
larger collaboration:

We observed the field of GRB 150213B (Pagani et al., GCN 17464) with the 
Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. 
Observations started on Feb 14.22 UT (6.86 hr after the GRB), and 
consisted of 4x300 s exposures in the SDSS r filter.

The optical afterglow (Pagani et al., GCN 17464; Kann et al., GCN 17465) 
is well detected in our images. A preliminary analysis yields a 
magnitude r = 22.10 +- 0.05 (AB), calibrated against nearby SDSS stars.

[GCN OPS NOTE(14feb15):  Per author's request, DX was added to the author list.]


GRB_name: GRB150213B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17468
SUBJECT: GRB 150213B: AAO optical observations
DATE:    15/02/14 07:06:15 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Pozanenko (IKI), R. Inasaridze (AAO), E. Mazaeva (IKI), A. Volnova (IKI), 
Molotov (KIAM), report on behalf of larger GRB follow-up collaboration:

We observed the field of the Swift GRB 150213B (Pagani et al., GCN 17464) 
with AS-32 (0.7m) telescope of Abastumani Observatory.   We obtained several 
unfiltered images starting on Feb. 13 (UT) 23:24:58 and ending Feb. 14 (UT) 
01:06:30. In the first single images of 120 s exposure we clearly detect 
the optical afterglow (Pagani et al., GCN 17464; Kann et al., GCN 17465; 
Malesani et al., GCN 17467).   Preliminary photometry of the afterglow is 
19.7m (at  54 minutes after burst trigger) in comparison with nearby 
USNO-B1.0 stars (R2 mags).

Data receiving and reduction is ongoing.


GRB_name: GRB150213B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17469
SUBJECT: GRB 150213B: Swift-XRT refined Analysis
DATE:    15/02/14 10:47:06 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. Maselli 
(INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), D.N.
Burrows (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU) and C.
Pagani report on behalf of the Swift-XRT team:

We have analysed 8.5 ks of XRT data for GRB 150213B (Pagani et al. GCN
Circ. 17464), from 133 s to 23.5 ks after the  BAT trigger. The data
comprise 414 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 refined XRT position is RA, Dec = 253.4520, +34.1884 which is
equivalent to:

RA (J2000): 16 53 48.49
Dec(J2000): +34 11 18.4

with an uncertainty of 3.6 arcsec (radius, 90% confidence).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=1.18 (+0.09, -0.10). At T+310 s  the decay
steepens to an alpha of 2.46 (+0.26, -0.23) before breaking again at
T+2218 s to a final decay with index alpha=1.33 (+0.24, -0.21).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.86 (+0.05, -0.04). The
best-fitting absorption column is  5.1 (+/-1.0) x 10^20 cm^-2, in
excess of the Galactic value of 1.9 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.74 (+0.29, -0.26)
and a best-fitting absorption column of 6.7 (+7.9, -4.8) x 10^20 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.7 x 10^-11 (4.2 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      6.7 (+7.9, -4.8) x 10^20 cm^-2
Galactic foreground: 1.9 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.74 (+0.29, -0.26)

If the light curve continues to decay with a power-law decay index of
1.33, the count rate at T+24 hours will be 1.6 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.9 x
10^-14 (6.6 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/00631051.

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


GRB_name: GRB150213B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17470
SUBJECT: GRB 150213B: RATIR Optical and NIR Observations
DATE:    15/02/14 15:42:07 GMT
FROM:    Nat Butler at Az State U  <natbutler@asu.edu>

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), Jos A. de Diego (UNAM), Leonid Georgiev (UNAM), Jess
Gonzlez (UNAM), Carlos Romn-Ziga (UNAM), Neil Gehrels (GSFC), and
Harvey Moseley (GSFC) report:

We observed the field of GRB 150213B (Pagani, et al., GCN 17464) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronmico Nacional on
Sierra San Pedro Mrtir from 2015/02 14.41 to 2015/02 14.55 UTC (11.27 to
14.72 hours after the BAT trigger), obtaining a total of 2.58 hours
exposure in the r, i, and z bands.

For a source within the Swift-UVOT error circle, in comparison with the
SDSS DR9, we obtain the following detections and upper limit (3-sigma):

  r = 22.4 +/- 0.6
  i = 22.1 +/- 0.1
  z > 20.50

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio Astronmico Nacional in San
Pedro Mrtir.


GRB_name: GRB150213B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17471
SUBJECT: GRB 150213B: Swift-BAT refined analysis
DATE:    15/02/14 16:02:52 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), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), C. Pagani (U Leicester), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL)
(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 150213B (trigger #631051)
(Pagani, et al., GCN Circ. 17464).  The BAT ground-calculated position is
RA, Dec = 253.448, 34.165 deg, which is 
   RA(J2000)  =  16h 53m 47.4s 
   Dec(J2000) = +34d 09' 54.5" 
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 13%.
 
The mask-weighted light curve shows a FRED peak with a few little peaks
starting at ~T+0, peaking at ~T+18, and returning to baseline at ~T+300 sec.
T90 (15-350 keV) is 181 +- 60 sec (estimated error including systematics).
 
The time-averaged spectrum from T+2.09 to T+249.78 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.80 +- 0.79, 
and Epeak of 54.8 +- 20.6 keV (chi squared 57.4 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 3.0 +- 0.4 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+18.08 sec in the 15-150 keV band is
1.1 +- 0.4 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.77 +- 0.15 (chi squared 63.4 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/631051/BA/


GRB_name: GRB150213B
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17472
SUBJECT: GRB 150213B: Swift/UVOT Detection
DATE:    15/02/14 18:21:33 GMT
FROM:    Frank Marshall at GSFC  <femarsha@khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and C. Pagani (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150213B
153 s after the BAT trigger (Pagani et al., GCN Circ. 17464).
A source consistent with the XRT position
(Osborne et al. GCN Circ. 17469)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  16:53:48.67 = 253.45278 (deg.)
    Dec (J2000) = +34:11:19.3  =  34.18869 (deg.)
with an estimated uncertainty of 0.46 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:

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

white              153          302          147         18.61 +/- 0.07
v                 4498        23548          966        >20.3
b                 3883        12039          961        >20.7
u                  310          532          218         18.76 +/- 0.15
w1                4910        10539         1082         20.76 +/- 0.21
m2                4703        16622         1224         21.25 +/- 0.32
w2                4293        22956         1279         21.48 +/- 0.31

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB150212A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17473
SUBJECT: GRB 150212A, the review of the sky area in plate archives
DATE:    15/02/14 18:49:48 GMT
FROM:    Valentyna Golovnya at Main Astro Obs,Kyiv  <golov_v@ukr.net>

V.V. Golovnya (Main Astro Obs., Kyiv)
report: 
We have undertaken the review of the sky area of GRB 150212A (P.A. Evans
GCN Circ. 17452) on astronegatives, collected in Ukrainian plate archive
(1976-1996). All the plates with the possible object appearance are
digitized using Epson Expression 10000XL flatbed scanner and the images
have been placed into Golosiiv Plate Archive database DBGPA with open
access to them. The list of plates is given in the table:

yyyymmdd/TimeUT   ---Plates----- Exp. -Mag- --USNO-B1--
19840720/21:19:40 GUA040C000430A 22.5 15.93 1373-0374987
19770622/22:14:06 GUA040C000535B 60.0 17.17 1374-0373547
19860716/21:18:54 GUA040C000961  16.0 17.42 1373-0374984
19870701/22:16:16 GUA040C001064  16.0 17.42 1373-0374984
19870822/19:11:46 GUA040C001078A 16.0 16.33 1373-0374866

Plates:â€“the plates archive identifier of DWA D/F=400/2000, M=103"/mm
(Marsden's number - 83) the plate number [1].
Exp. - Duration of the maximum exposures (minutes).
Mag - Limited Bmag, derived in the 7 minutes area around the location
given in Evans GCN Circ. 17452:
RA(J2000): 19h 01m 55.27s, Dec(J2000): +47d 21' 57.6".
USNO-B1 - Comparison star.
  The preview images of 5 areas together with the 7 min. of arc area
from Aladin can be found in
"http://gua.db.ukr-vo.org/img/grb/150212A/index.html".
The images with full resolution are available via e-mail on demand.

References:
1.L.Pakuliak DATABASE of GOLOSIIV PLATE ARCHIVE (DBGPA V2.0),
"http://gua.db.ukr-vo.org".


GRB_name: GRB150213B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17474
SUBJECT: GRB 150213B: P60 Observations
DATE:    15/02/14 20:16:02 GMT
FROM:    S. Bradley Cenko at NASA/GSFC  <brad.cenko@nasa.gov>

S. B. Cenko (NASA/GSFC) and D. A. Perley (Caltech) report on behalf of a larger collaboration:

We have imaged the location of GRB150213B (Pagani et al., GCN 17464) with the robotic Palomar 60 inch telescope.  Observations began at 10:15 UT on 2015 Feb 14 (dt ~ 11.7 hr after the Swift trigger) and were obtained in the SDSS g, r, i, and z filters.  We marginally detect the optical afterglow (Kann et al., GCN 17465; Malesani et al., GCN 17467; Pozanenko et al., GCN 17468; Butler et al., GCN 17470).  Using nearby point sources from SDSS for reference, we measure an r-band magnitude of r' = 22.65 +/- 0.33 - however we caution that the photometry is likely affected by the presence of the nearby bright star (e.g., Kann et al., GCN 17465).


GRB_name: GRB150213B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17475
SUBJECT: GRB 150213B: Enhanced Swift-XRT position
DATE:    15/02/16 07:39:45 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 5563 s of XRT Photon Counting mode data and 8 UVOT
images for GRB 150213B, 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 = 253.45234, +34.18876 which is equivalent
to:

RA (J2000): 16h 53m 48.56s
Dec (J2000): +34d 11' 19.5"

with an uncertainty of 1.6 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: GRB150219A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17476
SUBJECT: GRB 150219A: A long GRB detected by INTEGRAL
DATE:    15/02/19 13:30:46 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

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

a gamma ray burst lasting about 60 s has been detected by IBAS in the 
IBIS/ISGRI data at 12:31:14 UT of February 19

The refined coordinates (J2000) are:

R.A.= 271.2664  deg
DEC.=  -41.5849 deg

with an uncertainty of 2 arcmin (90% c.l.).

The burst had a peak flux of 1.4 counts/cm2/s (20-200 keV, 1-s integration 
time) and a fluence in the same energy range of about 4e-6 erg/cmq.

A plot of the light curve will  be posted at
http://ibas.iasf-milano.inaf.it/IBAS_Results.html


GRB_name: GRB150219A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17477
SUBJECT: GRB 150219A: Swift ToO observations
DATE:    15/02/19 15:04:27 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the INTEGRAL GRB 150219A. 
Automated analysis of the XRT data will be presented online at
http://www.swift.ac.uk/ToO_GRBs/00020483

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the INTEGRAL event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a 
GCN Circular after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

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


GRB_name: GRB150213B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17478
SUBJECT: GRB 150213B: AAO photometry
DATE:    15/02/19 16:49:54 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (IKI), A. Pozanenko (IKI), E. Mazaeva (IKI), R. Inasaridze 
(AAO), Sh. Makandarashvili (AAO),  Molotov (KIAM), report on behalf of 
larger GRB follow-up collaboration:

We report photometry of our observation (GCN 17468) of the field of the 
Swift GRB 150213B (Pagani et al., GCN 17464) with AS-32 (0.7m) telescope 
of Abastumani Observatory.  The optical afterglow (Pagani et al., GCN 
17464; Kann et al., GCN 17465; Malesani et al., GCN 17467) is visible on 
single images. The photometry of the afterglow  is following

Date       UT start   t-T0     Filter   Exp.    OT   Err.
                       (mid, days)       (s)
2015-02-13  23:22:23 0.03696   none     2*120  18.98 0.14
2015-02-13  23:27:43 0.04345   none     5*120  19.15 0.10
2015-02-13  23:41:05 0.05273   none     5*120  19.56 0.13
2015-02-13  23:54:27 0.06201   none     5*120  19.12 0.13
2015-02-13  24:07:49 0.07593   none     10*120 19.12 0.06
2015-02-13  24:34:32 0.09634   none     12*120 19.20 0.08

The photometry might be affected by the presence of the nearby bright 
star (e.g., Kann et al., GCN 17465). The photometry is based on nearby 
SDSS DR9 stars:

SDSS9_id            R(Lupton)
J165343,83+341043,0 16,49
J165348,15+341040,4 15,99
J165354,27+341137,8 17,87
J165339,38+341103,1 17,14
J165341,19+341135,8 14,53


GRB_name: GRB150219A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17480
SUBJECT: GRB 150219A: Swift-XRT afterglow detection
DATE:    15/02/19 23:34:23 GMT
FROM:    Valerio D'Elia at ASDC  <delia@asdc.asi.it>

K.L. Page (U. Leicester), C. Pagani (U. Leicester), A. Melandri
(INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), J.A. Kennea
(PSU), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), A.P. Beardmore
(U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

Swift-XRT has performed follow-up observations of the INTEGRAL-detected
burst GRB 150219A (Mereghetti et al. GCN Circ. 17476), collecting 2.6
ks of Photon Counting (PC) mode data between T0+10.5 ks and T0+23.4 ks.


An uncatalogued X-ray source is detected inside the INTEGRAL error
region and is fading with 3-sigma significance, and is therefore likely
the GRB afterglow.  The position of this source is RA, Dec=271.2507,
-41.5942 which is equivalent to:

RA (J2000): 18:05:0.18
Dec(J2000): -41:35:39.0

with an uncertainty of 3.7 arcsec (radius, 90% confidence).  This
position is 53 arcsec from the INTEGRAL position. 

The light curve can be modelled with a power-law decay with a decay
index of alpha=2.8 (+0.9, -0.7).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.8 (+/-0.4). The
best-fitting absorption column is  1.6 (+0.6, -0.5) x 10^22 cm^-2, in
excess of the Galactic value of 1.4 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 6.3 x 10^-11 (1.1 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.6 (+0.6, -0.5) x 10^22 cm^-2
Galactic foreground: 1.4 x 10^21 cm^-2
Excess significance: 4.6 sigma
Photon index:      1.8 (+/-0.4)

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 5.8 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.6 x
10^-14 (6.2 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis of the likely afterglow
are at http://www.swift.ac.uk/ToO_GRBs/00020483/index_1.php.
The results of the full analysis of the XRT observations are available
at http://www.swift.ac.uk/ToO_GRBs/00020483.

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


GRB_name: GRB150219A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17481
SUBJECT: GRB 150219A: Fermi GBM observation
DATE:    15/02/20 10:02:13 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) and C. Meegan (UAH) 
report on behalf of the Fermi GBM Team:

"At 12:31:12.26 UT on 19 February 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150219A (trigger 446041875 / 150219522), which
was also detected by INTEGRAL/IBIS (Mereghetti  et al. 2015, GCN 17476).
The GBM on-ground location is consistent with the INTEGRAL position.

The angle from the Fermi LAT boresight is 105 degrees.

The GBM light curve shows a structured pulse
with a duration (T90) of about 36 s (50-300 keV).
The time-averaged spectrum from T0-2.304 s to T0+38.657 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.92 (+0.08/-0.07)  and
the cutoff energy, parameterized as Epeak, is 202.7(+23.2/-19.1) keV.

The event fluence (10-1000 keV) in this time interval is
(1.00 +/- 0.05)E-05 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0+9.664 s in the 10-1000 keV band
is 4.2 +/- 0.3 ph/s/cm^2.

A Band function fits the spectrum equally well with Epeak=
166.7(+24.3/-17.3) keV, 
alpha = -0.82 +/- 0.10 and beta = -2.17 (+0.13/-0.24).

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


GRB_name: GRB150213B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17484
SUBJECT: GRB 150213B, the review of the sky area in plate archives
DATE:    15/02/21 16:24:17 GMT
FROM:    Valentyna Golovnya at Main Astro Obs,Kyiv  <golov_v@ukr.net>

V.V. Golovnya (Main Astro Obs., Kyiv)
report: 
We have undertaken the review of the sky area of GRB 150213B (J.P. Osborne
et al. GCN Circ. 17475) on astronegatives, collected in Ukrainian plate 
archive (1976-1996). All the plates with the possible object appearance are
digitized using Epson Expression 10000XL flatbed scanner and the images
have been placed into Golosiiv Plate Archive database DBGPA with open
access to them. The list of plates is given in the table:

yyyymmdd/TimeUT   ---Plates----- Exp. -Mag- --USNO-B1--
19770616/20:26:55 GUA040C000526B 60.1 17.26 1241-0248873
19770622/20:59:18 GUA040C000533B 60.0 17.26 1241-0248873
19770707/20:05:18 GUA040D000569A 29.7 17.20 1241-0248872
19770713/20:16:28 GUA040C000578B 30.0 17.20 1241-0248872
19770713/20:16:29 GUA040D000579  30.0 17.20 1241-0248872

Plates -the plates archive identifier of DWA D/F=400/2000, M=103"/mm
(Marsden's number - 083) the plate number [1].
Exp. - Duration of the maximum exposures (minutes).
Mag - Limited Bmag, derived in the 9 minutes area around the location
given in J.P. Osborne et al. GCN Circ. 17475:
RA(J2000): 16h 53m 48.56s, Dec(J2000): +34d 11' 19.5".
USNO-B1 - Comparison star.
  The preview images of 5 areas together with the 9 min. of arc area
from Aladin can be found in
â€œhttp://gua.db.ukr-vo.org/img/grb/150213B/index.htmlâ€.
The images with full resolution are available via e-mail on demand.

References:
1.L.Pakuliak DATABASE of GOLOSIIV PLATE ARCHIVE (DBGPA V2.0),
â€œhttp://gua.db.ukr-vo.orgâ€.


GRB_name: GRB150222A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  17486
SUBJECT: GRB 150222A: Swift detection of a burst
DATE:    15/02/22 17:11:54 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

M. G. Bernardini (INAF-OAB), S. D. Barthelmy (GSFC),
P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC),
J. A. Kennea (PSU), A. Melandri (INAF-OAB), D. M. Palmer (LANL) and
B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:

At 16:56:40 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150222A (trigger=632180).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 198.774, -12.137 which is 
   RA(J2000) = 13h 15m 06s
   Dec(J2000) = -12d 08' 11"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multiple-peaked
structure with a duration of about 15 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at ~6 sec after the trigger. 

The XRT began observing the field at 16:58:13.6 UT, 92.8 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 198.7865,
-12.1517 which is equivalent to:
   RA(J2000)  = 13h 15m 08.76s
   Dec(J2000) = -12d 09' 06.3"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 68 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 (3.31 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.9
(+2.52/-2.21) x 10^21 cm^-2 (90% confidence). 

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
0.05. 

Burst Advocate for this burst is M. G. Bernardini (grazia.bernardini 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.)


