# GCN_circulars

GRB_name: GRB091024A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10086
SUBJECT: GRB 091024: Burst was outside the Swift-BAT FOV after T0(BAT)+460sec
DATE:    09/10/26 21:20:21 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <takanori@milkyway.gsfc.nasa.gov>

T. Sakamoto (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), 
on behalf of the Swift-BAT team:

We reported the BAT refined analysis based on the event-by-event 
data only up to T+483 sec (T. Sakamoto et al., GCN Circ. GCN 10072).  
Since the Swift spacecraft slewed to the pre-planned target (GRB 091020) 
at T+415 sec, GRB 091024 became <5% coding by BAT at T+461 sec.  This 
is the reason why we only have the mask-weighted light curve data up 
to T+483 sec.  

However, we do see the 2nd and 3rd episodes reported by Fermi-GBM 
(Bissaldi et al., GCN Circ. 10070) and by Konus-Wind and Konus-RF 
(Golenetskii et al., GCN Circ. 10083) in the BAT raw light curve data.  
Although we can not confirm whether these 2nd and 3rd episodes are 
associated with GRB 091024 by the BAT imaging capability, the BAT 
observations are consistent with the later peaks being part of GRB 091024.  


GRB_name: GRB091026A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10087
SUBJECT: GRB 091026: Swift/UVOT Upper Limits
DATE:    09/10/26 22:38:01 GMT
FROM:    Peter Curran at MSSL  <pac@mssl.ucl.ac.uk>

P.A. Curran (MSSL-UCL) and C.B. Markwardt (CRESST/GSFC/UMD)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 091026 87 s 
after the BAT trigger (Markwardt et al., GCN 10081). No optical afterglow 
consistent with the enhanced XRT position (Evans et al., GCN 10084) is 
detected in the initial UVOT exposures. Preliminary 3-sigma upper limits 
using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for 
the first finding chart (FC) exposures and subsequent exposures are:


Filter          T_start(s)   T_stop(s)    Exp(s)    Mag
-----------------------------------------------------------
white (FC)      87           237          147       >21.00
u (FC)          300          550          246       >20.36

white           87           12292        950       >22.09
v               629          5959         236       >19.63
b               555          6778         235       >20.62
u               300          6573         462       >20.72
w1              678          6369         236       >20.09
m2              826          6164         216       >19.85
w2              605          16097        561       >20.70

The values quoted above are not corrected for the Galactic extinction due 
to the reddening of E(B-V) = 0.13 in the direction of the burst (Schlegel 
et al. 1998).


GRB_name: GRB091020A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10088
SUBJECT: Radio afterglow detection from GRB 091020
DATE:    09/10/26 23:00:25 GMT
FROM:    Dale A. Frail at NRAO  <dfrail@nrao.edu>

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

"We used the Very Large Array (VLA) to observe the field of view
towards the Swift burst GRB 091020A (GCN 10048, 10050, 10051) at a
frequency of 8.46 GHz. Data has been taken at 6 different epochs:
October 21.66, 22.54, 22.77, 22.99, 24.60 and 26.71 UT. The average
flux density of the source during the first 4 epochs was 108 +/- 25
uJy. The source has since increased in flux, rising to 230 +/- 42 uJy
on Oct 24.60 UT and 436 +/- 42 uJy on Oct. 26.71 UT. Our current
best-fit position is (J2000) R.A.=11:42:55.268, Dec.=+50:58:41.36 with
a conservative error of +/-0.6". Further observations are planned.

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


GRB_name: GRB091026A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10089
SUBJECT: GRB 091026: Swift-BAT refined analysis
DATE:    09/10/26 23:31:38 GMT
FROM:    Craig Markwardt at NASA/GSFC/UMD  <craigm@milkyway.gsfc.nasa.gov>

T. N. Ukwatta (GWU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
(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 091026 (trigger #373871)
(Markwardt, et al., GCN Circ. 10081).  The BAT ground-calculated position is
RA, Dec = 276.657, -86.113 deg which is 
   RA(J2000)  =  18h 26m 37.7s 
   Dec(J2000) = -86d 06' 47.2" 
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 36%.
 
The mask-weighted light curve shows a single FRED-like peak which starts
to rise around T-5 sec, peaks near T+0 sec, and has a long tail extending 
to about T+120 sec.  T90 (15-350 keV) is 41.6 +- 7.2 sec (estimated error 
including systematics).
 
The time-averaged spectrum from T-3.7 to T+47.9 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.53 +- 0.11.  The fluence in the 15-150 keV band is 1.8 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.18 sec in the 15-150 keV band
is 2.2 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/373871/BA/


GRB_name: GRB091020A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10090
SUBJECT: GRB 091020: Late TLS detection
DATE:    09/10/27 02:31:21 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, U. Laux, M. Roeder & H. Meusinger (TLS Tautenburg) report:

We observed again the afterglow of the Swift GRB 091020 (Racusin et al., 
GCN 10048) with the 1.34m Schmidt telescope of the Thueringer 
Landessternwarte Tautenburg, Germany, on the 26th of October, 5.2 days 
after the GRB. We obtained 11 x 600 sec images in Rc before clouds shut us 
down again. At the position of the afterglow, we detect a faint source in 
the stacked image.

We derive the following afterglow magnitudes using the same comparison 
star as Kann et al., GCN 10076:

dt  Filter mag dmag
____________________________________
5.213357 Rc 23.62 0.31


Kann et al., GCN 10076, found a single power-law decay with alpha = 1.12 
+/- 0.06. Compared to the extrapolation of this fit, there is no 
significant evidence for a break yet.

No further observations are possible due to an instrument change.

This message may be cited.


GRB_name: GRB091026A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10091
SUBJECT: GRB 091026: GROND Upper Limits
DATE:    09/10/27 05:38:20 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Robert Filgas (Tautenburg Obs.), Adria Updike (Clemson University), Arne
Rau, and Jochen Greiner (both MPE Garching) report on behalf of the GROND
team:

We observed the field of GRB 091026 (Swift trigger 373871; Markwardt et
al., GCN #10081) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla
Observatory (Chile).

Observations started at 00:48 UT on Oct 27, 2009, 11.6 hours after the GRB
trigger.  They were performed at an average seeing of 2" and at an average
airmass of 1.94.

We do not detect a source within the Swift-XRT error circle reported by
Evans et al. (GCN #10084) down to

g' > 24.8 mag,

r' > 24.2 mag,

i' > 23.9 mag,

z' > 23.7 mag,

J > 22.2 mag,

H > 21.3 mag and

K > 20.2 mag.

Magnitudes are given in the AB system and calibrated against USNO as well
as 2MASS field stars, and are not corrected for the expected Galactic
foreground extinction corresponding to a reddening of E_(B-V) = 0.13 mag
in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB091024A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10092
SUBJECT: GRB 091024: YNAO-GMG observations
DATE:    09/10/27 12:12:05 GMT
FROM:    Jirong Mao at Yunnan Obs  <jirongmao@ynao.ac.cn>

J. Mao (YNAO & INAF-OAB), S. Li and J. Bai (YNAO) report on behalf of the GMG group:

We observed the optical afterglow of GRB 091024 (Marshall et al., GCN 10062) using one 2.4-m telescope located at Gao-Mei-Gu (GMG, Yunnan Observatory) about 3 hours after the trigger. Some preliminary results are shown below:

Start UT   Filter  mag   err
-------------------------------------
11:52:13     R    19.66  0.02 
12:54:35     R    20.18  0.03  
15:11:33     R    21.03  0.05


All the calibrations were processed by nearby USNO stars in the images and without extinction correction. The detailed analysis is ongoing.
 
This message might be cited.


GRB_name: GRB091024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10093
SUBJECT: GRB 091024: Keck/LRIS Spectroscopy
DATE:    09/10/27 19:12:10 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. B. Cenko (UC Berkeley), M. M. Kasliwal and S. R. Kulkarni (Caltech)
report on behalf of a larger collaboration:

We have obtained optical spectra of the afterglow of GRB091024 (Marshall
et al., GCN 10062) with the Low Resolution Imaging Spectrometer mounted on
the 10-m Keck I telescope.  Observations began at 11:01 UT on 24 October
2009 (~ 2.1 hours after the burst) and covered the wavelength range from ~
3500 - 10000 A.

In addition to the features identified by Cucchiara, Fox, and Tanvir (CaII
H & K, Mg I), we also find strong absorption features we identify as Mg
II (2796 / 2803) and Fe II (2344, 2374, 2382, 2586, and 2600) at a common
redshift of z = 1.091.  The lack of Lyman-alpha absorption places an upper
limit of z <~ 1.9 on the redshift of GRB091024.


GRB_name: GRB091026A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10094
SUBJECT: GRB 091026: Suzaku WAM observation of the prompt emission
DATE:    09/10/28 07:03:39 GMT
FROM:    Norisuke Ohmori at Miyazaki U  <ohmori@astro.miyazaki-u.ac.jp>

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

The long GRB 091026 (Swift-BAT trigger #373871; Markwardt et al.,
GCN Circ. 10081) triggered the Suzaku Wide-band All-sky 
Monitor (WAM) which covers an energy range of 50 keV - 5 MeV
at 13:11:29.812 UT (=T0).

The observed light curve shows a multi-peaked structure, starting at
T0-1 s and ending at T0+13 s, with a total duration (T90) of about 9 s.
The fluence in 100 - 1000 keV was 1.47 (-0.40, +0.29) x 10^6 erg/cm^2.
The 1-s peak flux measured from T0+1.5 s was 0.59 (-0.30, +0.19)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0-1 s to T0+13 s is well fitted by a single power-law with 
 a photon index of 1.86 (-0.25, +0.33) (chi^2/d.o.f. = 77/50).
 
All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

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


GRB_name: GRB091020A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10095
SUBJECT: GRB 091020: Fermi GBM observation
DATE:    09/10/28 14:27:17 GMT
FROM:    Vandiver Chaplin at UAH/Fermi-GBM  <chapliv@email.uah.edu>

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

"At 21:36:43.82 UT on 20 October 2009, the Fermi
Gamma-Ray Burst Monitor triggered on GRB 091020
(trigger 277767405 / 091020900), which was also detected by
the Swift-BAT (Racusin et al., GCN 10048).
The angle from the Fermi LAT boresight of the Swift-XRT position
(Beardmore et al., GCN 10050) is 118 degrees.

The GBM light curve consists of a single pulse
with a duration (T90) of about 37 s (8-1000 keV).
The time-averaged spectrum from T0-7.7 s to T0+21 s is
best fit by a Band function with Epeak = 47.9 +/- 7.1 keV,
alpha = 0.2 +/- 0.4, and beta = -1.7 +/- .02.

The event fluence (8-1000 keV) in this time interval is
(1.0 +/- 0.2)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.5 s in the 8-1000 keV band
is 7.4 +/- 0.5 ph/s/cm^2.

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


GRB_name: GRB091029A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10097
SUBJECT: GRB 091029: Swift detection of a burst with an optical counterpart
DATE:    09/10/29 04:05:12 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

D. Grupe (PSU), J. R. Cummings (NASA/UMBC),
F. E. Marshall (NASA/GSFC), C. Pagani (PSU), D. M. Palmer (LANL),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 03:53:22 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091029 (trigger=374210).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 60.183, -55.994 which is 
   RA(J2000) = 04h 00m 44s
   Dec(J2000) = -55d 59' 37"
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 50 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~18 sec after the trigger. 

The XRT began observing the field at 03:54:41.9 UT, 79.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 60.17774, -55.95574 which
is equivalent to:
   RA(J2000)  = 04h 00m 42.66s
   Dec(J2000) = -55d 57' 20.7"
with an uncertainty of 4.4 arcseconds (radius, 90% containment). This
location is 138 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.14e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 1.80e-09 erg cm^-2 s^-1 (0.2-10
keV). 


UVOT took a finding chart exposure of 150 seconds with the White filter
starting 90 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 04:00:42.58 = 60.17742
  DEC(J2000) = -55:57:20.0  = -55.95555
with a 90%-confidence error radius of about 0.70 arc sec. This position is 2.3
arc sec. from the center of the XRT error circle. The estimated magnitude is
20.31 with a 1-sigma error of about 0.18. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02. 




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


GRB_name: GRB091029A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10098
SUBJECT: GRB 091029: GROND Detection of the Optical/NIR Afterglow
DATE:    09/10/29 04:42:35 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Robert Filgas (MPE Garching), Adria Updike (Clemson University), and
Jochen Greiner (MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 091029 (Swift trigger 374210; Grupe et al.,
GCN #10097) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla
Observatory (Chile).

Observations started at 03:57 UT on Oct 29, 4.5 min after the GRB trigger,
and are continuing. They were performed at an average seeing of 1.6" and
at an average airmass of 1.22.

We found a single point source within the 4.8 Swift-XRT error circle
reported by Grupe et al. (GCN #10097) at

RA (J2000) = 04h 00m 42.7 s

DEC (J2000) = -55d 57' 19

with an uncertainty of 0.5".

Based on the first 5.3 min of total exposures in g'r'i'z' and 6.7 min in
JHK, we estimate preliminary magnitudes (all in AB system) of

g' = 17.72 +- 0.1 mag,

r' = 17.45 +- 0.1 mag,

J = 17.00 +- 0.08 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: GRB091029A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10099
SUBJECT: GRB 091029: Skynet/PROMPT Observations of Peak and Fading
DATE:    09/10/29 06:56:42 GMT
FROM:    Aaron LaCluyze at U.North Carolina  <lacluyze@physics.unc.edu>

A. LaCluyze, D. Reichart, K. Ivarsen, J. Haislip, R. Egger, A. Foster, J. 
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. 
Nysewander report:

Skynet observed the Swift/BAT localization of GRB 091029 (Grupe et al., GCN 
10097) with three of the 16" PROMPT telescopes at CTIO beginning 46 seconds 
after the trigger in BRI through variable winds.

We detect the afterglow (Grupe et al., GCN 10097) in all filters.

The afterglow peaked in brightness approximately 5 - 6 minutes after the 
trigger, after which it has been fading with a power-law index of about 
-0.5.


GRB_name: GRB091029A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10100
SUBJECT: GRB 091029: Gemini-South Redshift
DATE:    09/10/29 07:49:19 GMT
FROM:    Ryan Chornock at UC Berkeley  <chornock@astro.berkeley.edu>

R. Chornock, D. A. Perley, and B. E. Cobb (UC Berkeley) report on behalf of a
larger collaboration:

We obtained optical spectra of the afterglow of GRB 091029 (Grupe et al., GCN
10097; Filgas et al., GCN 10098; LaCluyze et al., GCN 10099) using GMOS on
Gemini-South.  Our spectra cover the wavelength range of 3900-8100 angstroms
with the R400 grating.  Our first 600s exposure, starting at 06:06 UT on Oct. 29
(2.2 hr after the BAT trigger) reveals absorption lines from Lyman-alpha, C II,
C IV, Si II, and Si IV at a common redshift of 2.752, which we identify as
the redshift of the GRB.  The afterglow is still quite bright (R~17.8 mag at
t=2.02 hr) in the acquisition image.

We would like to thank German Gimeno and the Gemini staff for their assistance.


GRB_name: GRB091024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10101
SUBJECT: GRB091024 optical observations
DATE:    09/10/29 08:33:52 GMT
FROM:    Vladimir Sokolov at SAO RAS  <sokolov@sao.ru>

A. Moskvitin, T. Fatkhullin (SAO-RAS Niznijh Arkhyz, Russia),
on behalf of a larger colaboration, report:

We observed the field of the GRB 091024 afterglow (Marshall et al., GCN
10062) with the Zeiss-1000 telescope of SAO RAS, Russia. The observations
were carried out starting from October, 24.651 (15:37 UT) till October,
24.976 (23:26 UT). In total 29 * 300 sec. exposures in the Rc-band and
29 * 300 sec. exposures in the V-band were obtained. During the observations
we detected a faint fading object at the position reported by Mundell et al.
(GCN 10063) as well as a small extended object with R~20.8 in ~2 arcseconds
to the North-West from the afterglow (see also Kann and Laux GCN 10077).
The brightness of the OT in the first stacked R-band images (the mean epoch
is 16:52 UT) is R = 20.7 +/- 0.2 (we admit some contribution in flux from
the extended object). It is not clear at this stage if the extended object
is a host galaxy or a foreground galaxy responsible for the absorption line
system reported by Cucchiara et al. (GCN 10065) and Cenko et al.
(GCN 10093). The data analysis is in progress. Photometry was carried out
using nearby USNO B1.0 stars (R2 magnitudes).

This message may be cited.


GRB_name: GRB091029A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10102
SUBJECT: GRB 091029: Enhanced Swift-XRT position
DATE:    09/10/29 09:22:39 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 4524 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 091029, 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 = 60.17793, -55.95556 which is equivalent
to:

RA (J2000): 04h 00m 42.70s
Dec (J2000): -55d 57' 20.0"

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: GRB091029A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10103
SUBJECT: GRB 091029: Swift-BAT refined analysis
DATE:    09/10/29 13:30:45 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091029 (trigger #374210)
(Grupe, et al., GCN Circ. 10097).  The BAT ground-calculated position is
RA, Dec = 60.166, -55.954 deg, which is 
   RA(J2000)  =  04h 00m 40.0s 
   Dec(J2000) = -55d 57' 12.7" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 99%.
 
The mask-weighted light curve shows three overlapping peaks, the first starting
at ~T-10 sec, peaking at T+2, +20, and +26 sec, and ending at ~T+70 sec.
T90 (15-350 keV) is 39.2 +- 5 sec (estimated error including systematics).
 
The time-averaged spectrum from T-1.8 to T+60.2 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.46 +- 0.27, 
and Epeak of 61.4 +- 17.5 keV (chi squared 49.9 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.4 +- 0.1 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+19.12 sec in the 15-150 keV band is
1.8 +- 0.1 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.88 +- 0.06 (chi squared 57.4 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/374210/BA/


GRB_name: GRB091029A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10104
SUBJECT: GRB 091029: BOOTES-3 observations
DATE:    09/10/29 15:07:01 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

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

We have observed the afterglow of GRB 091029 (Grupe et
al. GCN 10097) using the 0.6m Yock-Allen robotic telescope
(BOOTES-3). A 24x60s combined unfiltered exposure with
mid epoch October 29.450 UT (6.9 h after the burst) shows the
afterglow at a magnitude of R = 18.5 +/- 0.2 as compared to
USNO-B1 star n. 0340-0030266 (RA, Dec = 04:00:39.53,
-55:56:55.17, R2 = 16.66).

A finding chart can be found at:
http://www.brera.inaf.it/utenti/deugarte/GRB/091029/b3_091029.jpg

Further analysis is ongoing.

[GCN OPS NOTE(30oct09):  Per author's request, "B.A. Allen"
was changed to "W.H. Allen".]


GRB_name: GRB091029A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10106
SUBJECT: GRB 091029: Swift XRT refined analysis
DATE:    09/10/29 19:46:14 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

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

We have analyzed the first 7 orbits of  XRT data of GRB 091029
(Grupe et al. GCN Circ.  10097). The data comprise 69 s in Windowed
Timing (WT) mode and 15727 s in Photon Counting (PC) mode. The
enhanced XRT position has already been determined by Goad et al.
(GCN circ. 10102).

A spectrum formed from the WT mode data can be fitted with an
absorbed  power-law with a photon spectral index of 2.30+/-0.08
with an  absorption column density consistent with the Galactic
value of 1.14 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode
spectrum (excluding the flare around 300 s after the burst) results
in a slightly flatter X-ray spectrum with Gamma = 2.00+/-0.07.

The light curve (excluding the flares) can be modelled with a
double broken power-law decay with an initial decay slope
alpha-1 = 3.76+0.21-0.19 with the first break at 358+48-31 s
after the trigger followed by a plateau phase with a decay slope
alpha-2 = -0.17+/-0.22 and a second break at 3640+3450-1270 s.
After this break the decay slope is alpha-3 = 0.76+0.06-0.05.
If the afterglow continues to decay with a slope of 0.76, the
predicted count rates 24, 48, and 72  hours after the trigger are
0.033 counts s^-1 or 1.12e-12 ergs s^-1 cm^-2,
0.020 counts s^-1 or 6.80e-13 ergs s^-1 cm^-2,
0.014 counts s^-1 or 4.76e-13 ergs s^-1 cm^-2, respectively.



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


GRB_name: GRB091029A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10107
SUBJECT: GRB 091029: Skynet/PROMPT Continued Observations of Fading
DATE:    09/10/29 20:37:05 GMT
FROM:    Aaron LaCluyze at U.North Carolina  <lacluyze@physics.unc.edu>

A. LaCluyze, D. Reichart, J. Haislip, K. Ivarsen, R. Egger, A. Foster, J. 
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. 
Nysewander report:

Skynet continued to observe the afterglow (Grupe et al., GCN 10097) of GRB 
091029 (Grupe et al., GCN 10097) with three of the 16" PROMPT telescopes at 
CTIO in BRI.

After peaking in brightness 5 - 6 minutes after the trigger (LaCluyze et 
al., GCN 10099) the afterglow continued to fade as a power-law of index 
approximately -0.5 (LaCluyze et al., GCN 10099) until at least 4.7 hours 
after the trigger.

At 4.7 hours after the trigger, the afterglow's magnitude was I = 18.52 +/- 
0.06 (statistical) +/- 0.41 (systematic; calibrated to 125 USNO B1 stars).

Skynet's most recent BRI light curve, calibrated to USNO B1 stars, can be 
found here:

http://skynet.unc.edu/grb/grb091029.png


GRB_name: GRB091029A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10108
SUBJECT: GRB091029: Swift/UVOT observations
DATE:    09/10/29 21:13:14 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F. E. Marshall (GSFC) and D. Grupe (PSU) report on  
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 091029
91 sec. after the BAT trigger (Grupe et al., GCN Circ. 10097). 
We detect the optical afterglow at the refined UVOT position
RA, Dec 60.17745, -55.95557, which is

     RA  (J2000)  04:00:42.59
     Dec (J2000) -55:57:20.0

with an estimated uncertainty of 0.55 arcsec (radius, 90% confidence).
This position is consistent with the enhanced XRT position (Goad
et al., GCN 10102). The detection in the white, v, b and u filters and
not in the UV filters is consistent with the redshift
of 2.752 (Chornock et al., GCN 10053).

The afterglow brightened by a factor of 4 between the first two
observations in the white filter, which had mean observing times
of T+166 s. and T+594s. The afterglow then decayed following
an approximately power law form with a decay index of -0.45.
This decay form lasted until at least T+8231 s.
A similar optical light curve was reported by LaCluze et al.
(GCN Circ. 10099 and 10107).

Preliminary magnitudes and 3 sigma upper limits are reported below.

Filter    T_start(s) T_stop(s)  Exposure(s)   Mag  Err
------------------------------------------------------------------------
white        91        240       147          20.22 +/- 0.13
white       584        603        19          18.75 +/- 0.14
v           635        654        19          17.81 +/- 0.26
b           559        578        19          19.04 +/- 0.28
u           303        552        19          18.42 +/- 0.08
uvw1        684       1280        58          > 19.32
uvm2       1930       1949        19          > 18.74
uvw2        611       1206        58          > 20.45
-------------------------------------------------------------------------

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.02 mag (Schlegel et al.,
1998, ApJS, 500, 525).  The photometry is on the UVOT photometric system
described in Poole et al. (2008, MNRAS, 383,627).


GRB_name: GRB090920A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10109
SUBJECT: GRB 090920: Skynet/DSO Detection
DATE:    09/10/29 21:38:15 GMT
FROM:    Aaron LaCluyze at U.North Carolina  <lacluyze@physics.unc.edu>

LaCluyze, A., D. Reichart, A. Smith, D. Caton, L. Hawkins, J. Haislip, K. 
Ivarsen, R. Egger, A. Foster, J. Moore, A. Oza, M. Schubel, J. Styblova, A. 
Trotter, J. A. Crain, and M. Nysewander report:

Skynet observed the Swift/BAT localization of GRB 090920 (Racusin et al., 
GCN 10048) with the 14" Dark Sky Observatory telescope in North Carolina 
beginning 12.0 hours after the trigger in I.

We detect the afterglow (Racusin et al., GCN 10048).  Stacking only images 
that increase the limiting magnitude yields:

mean                                                         1-sig.  1-sig.
time                                                         sys.    stat.
since                                             cal.       cal.    cal.
trig.  tel.    exp.      fil.  magnitude          stars*     unc.    unc.
(h)            (# x s)                                       (mag)   (mag)

12.6   DSO-14  18 x 160  I     19.75 +0.26 -0.21  13 SDSS 7  0.020   0.001

* Transformed using Jester et al., 2005, ApJ, 130, 873.


GRB_name: GRB091018A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10110
SUBJECT: GRB 091018, SMARTS optical/IR afterglow observations
DATE:    09/10/29 21:47:42 GMT
FROM:    Bethany Cobb at UC Berkeley  <bcobb@astro.berkeley.edu>

B. E. Cobb (UC Berkeley) reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained 
optical/IR imaging of the error region of GRB 091018 (GCN 10034, 
Stamatikos et al.) over several epochs, starting ~3.9 hours post-burst. 
For the first epoch, several dithered images were obtained in each filter,
with total summed exposure times of 180s in each of BRIJK and 120s in each 
of H and V.  For later epochs, total summed exposure times amounted to 15 
minutes in I and V and 12 minutes in J and K.

At a mid-exposure time of 2009-10-19 00:57 UT (4.1 hrs post-burst), the 
GRB afterglow (e.g. GCN 10034, Stamatikos et al., GCN 10036, Schaefer et 
al., GCN 10039, Filgas et al.) is detected with the following magnitudes:

B = 19.59 +/- 0.04
V = 19.27 +/- 0.05
R = 18.88 +/- 0.04
I = 18.44 +/- 0.04
J = 18.0 +/- 0.2
H = 17.1 +/- 0.2
K = 16.1 +/- 0.2

Between 4.1 hrs and 33.0 hrs post-burst, the GRB afterglow fades with a 
decay rate of approximately alpha = -1.3 (where afterglow flux is 
proportional to t^alpha).

time
post-burst      I-band magnitude
4.1 hrs         18.44 +/- 0.04
5.5 hrs         18.82 +/- 0.04
8.0 hrs         19.26 +/- 0.04
9.7 hrs         19.49 +/- 0.05
28.6 hrs        21.04 +/- 0.06
33.0 hrs        21.27 +/- 0.08

(Optical photometry is calibrated against Landolt standard stars
and IR photometry is calibrated against 2MASS stars in the field.)


GRB_name: GRB091029A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10111
SUBJECT: GRB 091029, SMARTS optical/IR afterglow observations
DATE:    09/10/29 23:30:19 GMT
FROM:    Bethany Cobb at UC Berkeley  <bcobb@astro.berkeley.edu>

B. E. Cobb (UC Berkeley) reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained 
optical/IR imaging of the error region of GRB 091029 (GCN 10097, Grupe et 
al.) with a mid-exposure time of 50 minutes post-burst (2009-10-29 04:43 
UT). Total summed exposure times amounted to 36 minutes in I and 30 
minutes in J. Imaging was done under poor (2.5") seeing conditions.

The afterglow of GRB 091029 (e.g. GCN 10097, Grupe et al.; GCN 10098, 
Filgas et al.; GCN 10099, LaCluyze et al.) is detected in our images. 
Preliminary comparison to USNO-B1.0 stars in I and 2MASS stars in J 
indicates the following afterglow magnitudes:

time post-burst         I mag           J mag
50 minutes              17.9+/-0.1      17.6+/-0.1

In individual I-band images, the afterglow fades by ~0.4 magnitudes 
between 30 and 69 minutes post-burst. During this time, the afterglow 
exhibits a shallow decay rate of alpha ~ -0.4+/-0.1 (where afterglow flux 
is proportional to t^alpha), which is consistent with the decay rate 
measured by LaCluyze et al. (GCN 10099).


GRB_name: GRB091018A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10112
SUBJECT: GRB 091018: Skynet/PROMPT Observations of Possible Host Galaxy
DATE:    09/10/30 04:17:19 GMT
FROM:    Aaron LaCluyze at U.North Carolina  <lacluyze@physics.unc.edu>

A. LaCluyze, D. Reichart, J. Haislip, K. Ivarsen, R. Egger, A. Foster, J. 
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. 
Nysewander report:

Skynet has continued to observed the afterglow (Stamatikos et al., GCN 
10034) of GRB 091018 (Stamatikos et al., GCN 10034) with two of the 16" 
PROMPT telescopes at CTIO in RI (LaCluyze et al., GCNs 10046, 10061).

Between 3.2 and 7.5 days after the trigger, the light curve is consistent 
with constant emission, which suggests that we are observing the host 
galaxy.

If so, we measure its brightness to be:

R = 22.30 +/- 0.11 (statistical) +/- 0.56 (systematic; calibrated to 115 
USNO B1 stars).

and

I = 21.78 +/- 0.16 (statistical) +/- 0.54 (systematic; calibrated to 67 
USNO B1 stars).


GRB_name: GRB090926A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10113
SUBJECT: GRB 090926a, SMARTS optical/IR afterglow observations
DATE:    09/10/30 07:27:25 GMT
FROM:    Bethany Cobb at UC Berkeley  <bcobb@astro.berkeley.edu>

B. E. Cobb (UC Berkeley) reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 090926a
(GCN 9933, Bissaldi et al.) over several epochs.  For each epoch,
total summed exposure times amounted to 36 minutes in I and
30 minutes in J.

The afterglow of GRB 090926a (e.g. GCN 9937, Haislip et al.;
GCN 9938, Gronwall et al.) is detected in our images with
the following magnitudes (calibrated using Landolt standard stars
in the optical and 2MASS stars in the IR):

time
post-burst      I mag           J mag
20.60 hrs       18.17+/-0.06    17.28+/-0.07
71.74 hrs       19.53+/-0.07    18.35+/-0.09
119.18 hrs      20.33+/-0.10    19.16+/-0.13

Between ~21 and 119 hours post-burst, the afterglow fades
with a rate of alpha ~ -1.1+/-0.1 (where afterglow flux is
proportional to t^alpha).


GRB_name: GRB091024A
Detection_method: Fermi LAT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10114
SUBJECT: GRB 091024: Fermi LAT upper limits
DATE:    09/10/30 19:29:08 GMT
FROM:    Aurelien Bouvier at Stanford  <bouvier@slac.stanford.edu>

Aurelien Bouvier (SLAC), Julie McEnery (NASA/GSFC), Jim Chiang  
(SLAC), Dan Kocevski (SLAC), Elena Moretti (INFN Trieste), Vlasios  
Vasileiou (NASA/GSFC & UMBC) and Frederic Piron (LPTA) report on  
behalf of the Fermi LAT team:

We present the flux and fluence upper limits based on the non- 
detection of GRB 091024 (trigger 278067360 / 091024372) by the Fermi  
Large Area Telescope (Fermi LAT) in the 0.1-300 GeV energy range.  
This burst was detected by Swift (GCN 10062) and the Fermi Gamma-ray  
Burst Monitor with a first emission interval lasting ~50 sec and a  
second emission interval starting ~630 sec after trigger and lasting  
more than 400 sec (GCN 10070). The spacecraft performed a repointing  
maneuver for this burst which resulted in pointed observation for 5  
hours starting ~350 sec after trigger.
No significant emission was detected in the LAT energy range during  
any of the time intervals in which the burst was in the LAT field of  
view. We computed the 95% CL upper limits using a bayesian method  
(Helene O., 1983, N.I.M. 212, 319) and our background estimation tool  
(described in Abdo et al. 2009: arXiv:0910.4192) on the LAT energy  
flux and fluence for the time interval T0+350 to T0+2000 sec with  
respect to the GRB trigger time T0 (08:55:58.47 UT, October 24th  
2009) and with an assumed spectral index of -2.2:
- 95% Energy Flux Upper Limit = 9.4e-10 erg/cm^2/sec
- 95% Energy Fluence Upper Limit = 1.5e-6 erg/cm^2
The upper limit results presented above are preliminary; final  
results will be published in the Fermi LAT GRB Catalog. 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: GRB091031A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10115
SUBJECT: GRB 091031: Fermi GBM detection
DATE:    09/11/01 17:36:50 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

S. McBreen (UCD/MPE) and V. Chaplin (UAH)
report on behalf of the Fermi GBM Team:

"At 12:00:28.85 UT on 31 October 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091031 (trigger 278683230 / 091031500).

The on-ground calculated location, using the GBM trigger
data, is RA = 70.6, DEC = -59.1 (J2000 degrees,
equivalent to 04 h 42 m, -59 d 06 '), with an uncertainty
of 1 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 22 degrees.

The GBM light curve consists of a number of pulses with
sub-structure and has a duration (T90) of about 35 s (8-1000 keV).
The time-averaged spectrum from T0-0.003 s to T0+36.609 s is
best fit by a Band function with Epeak = 503.10 (+47.30/-46.60) keV,
alpha = -0.91 +/- 0.04, and beta = -2.34 (+0.19/-0.31)
(CSTAT 674 for 602 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(2.05 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+6.9 s in the 8-1000 keV band
is 7.5 +/- 0.3 ph/s/cm^2.

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

[GCN OPS NOTE(01nov09): Per author's request, the missing minus sign
to the value for alpha was added.]


GRB_name: GRB091024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10116
SUBJECT: GRB 091024: optical observations
DATE:    09/11/01 22:00:15 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of  the Swift GRB 091024 (Marshall  et al., GCN 10062) 
with ZTE telescope of  Crimean branch of SAI MSU in  R-filter on Oct.24 
between  (UT) 16:18:50 - 00:04:47 and Oct.25 19:07:19 - 19:48:19 under 
moderate seeing of about 3". In initial images we detect fading afterglow 
(Mundell et al., GCN 10063). In a combined image of the Oct. 24 the 
afterglow looks like extended due to the nearby NW object reported by 
Moskvitin et al. (GCN 10101).

In a preliminary data reduction we do not separate afterglow and nearby 
object. The astrometry of the afterglow + nearby object is following

Oct.24
RA(J2000):  22 36 59.61
Dc(J2000): +56 53 23.1
with uncertainty of  0.5 arcsec

Oct.25
RA(J2000):  22 36 59.33
Dc(J2000): +56 53 24.5
with uncertainty of  0.5 arcsec

The coordinates of Oct. 24 consistent with afterglow coordinates (Mundell et 
al., GCN 10063, Henden et al. GCN 10073, Chornock et al. GCN 10075). The 
angular distance between astrometry results is 2.7"  suggests a prevalence 
of the afterglow on Oct.24 and nearby object on Oct.25. Taking into account 
the redshift of z = 1.091 (Cucchiara et al. GCN 10065, Cenko et al. GCN 
10093) one can estimate the distance between afterglow and object as 22 kpc 
and the nearby object could be the host galaxy of GRB 091024 as suggested 
early (Moskvitin et al. GCN 10101).

A preliminary photometry of the afterglow+nearby object is based on 
reference star  USNO B1.0 1468-0448529 (22 36 55.66 +56 53 04.2) assuming 
R=17.30:

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

0.3210  R       600  18.31 +/-0.07
0.3283  R       600  18.56 +/-0.08
0.3356  R       600  18.72 +/-0.08
0.3429  R       600  18.56 +/-0.08
0.3522  R       600  18.73 +/-0.08
0.3595  R       600  18.80 +/-0.09
0.3668  R       600  18.89 +/-0.11
0.3741  R       600  18.70 +/-0.08
0.3814  R       600  19.20 +/-0.16
0.3887  R       600  19.16 +/-0.16
0.3960  R       600  18.86 +/-0.15
0.4076  R       780  19.44 +/-0.34
0.5706  R       1260 19.11 +/-0.08
0.5873  R       1320 19.15 +/-0.09
1.4386   R      2340  20.7  +/- 0.2

We caution that afterglow photometry above is contaminated by the nearby 
object which we suggest as a candidate of host galaxy. The combined image 
can be found at http://grb.rssi.ru/GRB091024/GRB091024a_091024_R_ZTE.gif
where vertical tick points out the afterglow and horizontal one points out 
the nearby object. 


GRB_name: GRB091102A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10117
SUBJECT: GRB 091102: Swift detection of a burst
DATE:    09/11/02 14:43:58 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

E. A. Hoversten (PSU), A. P. Beardmore (U Leicester),
D. N. Burrows (PSU), P.A. Curran (MSSL-UCL), C. Guidorzi (U Ferrara),
J. A. Kennea (PSU), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB),
P. T. O'Brien (U Leicester), C. Pagani (PSU),
K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU),
M. A. Stark (PSU), M. C. Stroh (PSU), T. N. Ukwatta (GSFC/GWU) and
L. Vetere (PSU) report on behalf of the Swift Team:

At 14:34:38 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091102 (trigger=374598).  Swift did not slew immediately 
to the burst due to an observing constraint. 
The BAT on-board calculated location is 
RA, Dec 72.674, -72.510 which is 
   RA(J2000) = 04h 50m 42s
   Dec(J2000) = -72d 30' 34"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 10 sec.  The peak count rate
was ~5000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

Due to an observing constraint, Swift will not slew until 
T0+13.6 minutes. There will be no XRT or UVOT data until
this time.  We will issue another circular at when those 
data are available. 

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


GRB_name: GRB091102A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10118
SUBJECT: GRB 091102: Swift/UVOT Finding Chart Observation
DATE:    09/11/02 15:09:46 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) reports on behalf of the Swift/UVOT team:

UVOT observed GRB 091102 (Hoversten et al., GCN Circ 10117) with a
finding chart exposure of 150 seconds with the White filter starting
985 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 8'x8' region for the list of
sources generated on-board covers 100% of the BAT 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 expected extinction
corresponding to E(B-V) of 0.07.


GRB_name: GRB091102A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10119
SUBJECT: GRB 091102: ROTSE-III Optical Limits
DATE:    09/11/02 15:34:52 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

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

ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to
GRB 091102 (Swift trigger 374598; Hoversten et al., GCN 10117), producing
images beginning 5.8 s after the GCN notice time. An automated response
took the first image at 14:35:04.8 UT, 26.5 s after the burst, under fair
conditions with occassional thin clouds and a bright Full Moon 96 degrees
away. We took 10 5-sec, 10 20-sec and 100 60-sec exposures. These
unfiltered images are calibrated relative to USNO A2.0 (R). Imaging is on
going.

Comparison to the DSS (second epoch) reveals no new sources within the
3-sigma Swift/BAT error circle, for both single images and coadding into
sets of 10.  No XRT position is available.  Individual images have
limiting magnitudes ranging from 13.7-16.0; we set the following specific
limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
14:35:04.8   14:35:09.8         5     14.6           26.5       N
14:35:04.8   14:37:16.8        50     15.5           26.5       Y
14:37:25.9   14:42:08.0       282     16.6          167.6       Y


GRB_name: GRB091102A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10120
SUBJECT: GRB 091102: Swift/XRT localization
DATE:    09/11/02 18:42:23 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>

J.A. Kennea, C. Pagani, E.A. Hoversten (PSU), P.A. Evans and M.R. Goad (U.
Leicester) report on behalf of the Swift-XRT team:

Using 289 s of XRT Photon Counting mode data and 1 UVOT images, we find a
possible afterglow candidate with an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources to
the USNO-B1 catalogue): RA, Dec = 72.61610, -72.51970 which is equivalent
to:

RA (J2000):  04 50 27.87
Dec (J2000): -72 31 10.9

with an uncertainty of 2.2 arcsec (radius, 90% confidence), 72 arcseconds
from the BAT position reported by Hoversten et al. (GCN #10117).

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).

Currently we cannot confirm any fading in this afterglow candidate.
Observations are on-going.

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


GRB_name: GRB091102A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10121
SUBJECT: GRB 091102: Swift-BAT refined analysis
DATE:    09/11/02 22:06:25 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), E. A. Hoversten (PSU),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091102 (trigger #374598)
(Hoversten, et al., GCN Circ. 10117).  The BAT ground-calculated position is
RA, Dec = 72.622, -72.527 deg which is 
   RA(J2000)  =  04h 50m 29.3s 
   Dec(J2000) = -72d 31' 37.9" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 80%.
 
Because the s/c slewed for an observing constraint, the burst location
went out of the BAT FOV at T+160 sec, and then came back into the FOV
at T+900 sec.  The mask-weighted light curve shows a couple slightly overlapping
peaks starting at ~T-2 sec, and ending at ~T+20 sec.  There is now measurable
flux at T+900 sec when the location comes back into the FOV.  T90 (15-350 keV)
is 6.6 +- 0.5 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.8 to T+6.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.08 +- 0.12.  The fluence in the 15-150 keV band is 5.2 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.26 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/374598/BA/


GRB_name: GRB091102A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10122
SUBJECT: GRB 091102: BOOTES-3 observations
DATE:    09/11/02 23:26:42 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

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

"We have observed the field of GRB 091102 (Hoversten et al.
GCN 10117) with the 0.6m Yock-Allen robotic telescope
(BOOTES-3) in Bleinheim, New Zealand. The observations were
obtained with clear filter and began at 14:35:04 UT (26
seconds after the burst). As stated by Schaefer et al.
(GCN 10119) using ROTSE-III data, there is no obvious
counterpart within the BAT error box. Inspection of the XRT
error circle shows a source at the South-Western edge that
is present both in the DSS and in 2MASS. Combining early
images we detect a further low signal source, with
coordinates (J2000) 04:50:27.22, -72:31:10.3. We note
however, that this is a preliminary reduction and that the
detection cannot be secure at this point. In the following
address we provide a finding chart indicating the location
of the source:

http://www.iaa.es/~mates/091102_BOOTES3.jpg

t-t0(s)   Exp(s)   Mag
===============================
72        39x2     19.07+/-0.35
406       107x2    19.36+/-0.35
530       60x5     > 19.96
83        19x30    > 19.25
2708      47x60    > 20.30
===============================

For the photometry we have used the star located at the
coordinates (J2000) 04 50 26.58, -72 31 35.3, assuming a
magnitude of 16.14."

[GCN OPS NOTE(02nov09):  The Subject-line was changed from 091103
to 091102.]


GRB_name: GRB091102A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10123
SUBJECT: GRB 091102: GROND Upper Limits
DATE:    09/11/03 04:21:46 GMT
FROM:    Felipe Olivares Estay at MPE  <felipe@mpe.mpg.de>

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

We observed the field of GRB 091102 (Swift trigger 374598; Hoversten
et al., GCN #10117) simultaneously in g'r'i'z'JHK with GROND (Greiner
et al. 2008, PASP, 120, 405) mounted at the 2.2 m ESO/MPI telescope at
La Silla Observatory (Chile). Observations started on November 3 at
00:02 UT, 9.5 hours after the GRB trigger. They were performed from
the beginning of the astronomical twilight at an average seeing of 2"
and at an average airmass of 2.15.

Although the source at the South-Western edge of the 2.2" Swift/XRT
error circle (Kennea et al., GCN #10120) reported by De Ugarte Postigo
et al. (GCN #10122) is clearly seen, we do not detect the afterglow
candidate in co-added images of 49.2 min integration time in g'r'i'z'
and 40 min in JHK down to the following limiting magnitudes (all in
the AB system):

r' > 23.1 mag,
i' > 22.9 mag,
z' > 23.1 mag,
J > 20.6 mag,
H > 20.5 mag, and
K > 19.0 mag,

calibrated against GROND zeropoints and 2MASS field stars. No
corrections for the expected Galactic foreground extinction were made,
which correspond to a reddening of E(B-V)=0.14 mag in the direction of
the burst (Schlegel et al. 1998).


GRB_name: GRB091102A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10124
SUBJECT: GRB 091102: Swift/UVOT Upper Limits
DATE:    09/11/03 05:23:32 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 091102
986s after the BAT trigger (Hoversten et al., GCN 10117). We do not
detect any source at the enhanced Swift XRT position (Kennea et
al. GCN 10120). UVOT magnitude 3-sigma upper limits are reported in
the following table:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
WHITE       986     1136     147          > 20.05
v          1267     1287      19          > 17.18
b          1193     1213      19          > 18.09
u          1168     1188      19          > 17.70
uvw1       1144     1164      19          > 17.70
uvm2       1292     1301       9          > 16.61
uvw2       1243     1263      19          > 17.79

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.07 mag
(Schlegel et al. 1998). All photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB091102A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10125
SUBJECT: GRB 091102: Swift-XRT refined analysis
DATE:    09/11/03 06:23:30 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

L. Vetere and E. A. Hoversten (PSU) report on behalf of the Swift-XRT  
team:

We have analysed 1.4 ks of XRT data for GRB 091102 (Hoversten et al.  
GCN Circ.
10117), from 988 s to 19 ks after the BAT trigger. The data are  
entirely in
Photon Counting (PC) mode. The enhanced XRT position has already been  
determined
by Kennea et al. (GCN Circ. 10120).

The PC light curve shows a steep drop at 1.3 ks after the BAT trigger  
with a
decay index of alpha=2.9 +/- 0.6.

A spectrum formed from the PC mode data can be fitted with an absorbed  
power-law
with a photon spectral index of 2.0 (+0.8, -0.6). The best-fitting  
absorption
column is 2.4 (+2.5, -1.3) x 10^21 cm^-2, consistent with the Galactic  
value of
1.1 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed  
(unabsorbed)
0.3-10 keV flux conversion factor deduced from this spectrum is 4.2 x  
10^-11
(6.3 x 10^-11) erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00374598.

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


GRB_name: GRB091102A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10126
SUBJECT: GRB 091102A: Fermi GBM observation
DATE:    09/11/03 09:40:50 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

Arne Rau (MPE) reports on behalf of the Fermi GBM Team:

"At 14:34:38.36 UT on 2 November 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091102A (trigger 278865280  / 091102607) which
was also detected by the Swift-BAT (Hoversten et al. 2009, GCN 10117).
The GBM on-ground location is consistent with the Swift/XRT position
(Kennea et al. 2009, GCN 10120).
 
The angle from the Fermi LAT boresight is 94 degrees.

The GBM light curve consists of two peaks with a duration (T90)
of about 7.3 +/- 0.4 s (8-1000 keV). The time-averaged spectrum
from T0-1.792 s to T0+3.328 s is adequately by a simple power
law function with index -1.24 +/- 0.03 (C-stat 478 for 387 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(2.1 +/- 0.1)E-06 erg/cm^2. The 1.273-sec peak photon flux measured
starting from T0+0.003 s in the 8-1000 keV band
is 2.9 +/- 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: GRB091102A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10127
SUBJECT: GRB 091102 : Faulkes Telescope South Upper Limits
DATE:    09/11/03 12:07:11 GMT
FROM:    Zach Cano at ARI/John Moores Liverpool  <zec@astro.livjm.ac.uk>

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

Following Swift detection of GRB 091102 (Hoversten et al. GCN Circ.
10117), Faulkes Telescope South (Australia) reacted automatically and
began observing at 14:37:06 UT in BVRi.  We detect no new source within
the XRT error circle (Baumgartner et al., GCN 10121).

In our first R-band image, which is contemporaneous with the images taken
by A. de Ugarte Postigo et al. (GCN 10122), we do not detect their
afterglow candidate.

We have attached a finder chart of the GCN field (taken at T-To=186s):

http://www.fe.infn.it/u/guidorzi/GRB091102/091102_FTS_DM.jpg

We find the following upper limits, as calibrated against nearby USNO
object 0174-0110239:

T_exp     T-T0(mid exposure)    mag_limit
-----------------------------------------
30s             186 s           R2 > 19.7
120s            2.07 hrs        B2 > 18.7
120s            2.18 hrs        I2 > 20.7
120s            2.12 hrs        R2 > 20.2


GRB_name: GRB091010A
Detection_method: Fermi LAT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10128
SUBJECT: Fermi LAT Upper Limits on GRB 091010
DATE:    09/11/03 17:12:28 GMT
FROM:    Daniel Kocevski at UC Berkeley  <kocevski@berkeley.edu>

Daniel Kocevski (SLAC), Aurelien Bouvier (SLAC), Julie McEnery
(NASA/GSFC), Jim Chiang  (SLAC), Elena Moretti (INFN Trieste), Vlasios
Vasileiou (NASA/GSFC & UMBC) and Frederic Piron (LPTA) report on
behalf of the Fermi LAT team:

We present the flux and fluence upper limits based on the
non-detection of GRB 091010 (trigger 276835391 / 091010113) (GCN
10004, GCN 10018) by the Fermi Large Area Telescope (Fermi LAT) in the
0.1-300 GeV band. As reported by Kienlin et al. 2009, GCN 10018, GRB
091010 was well detected by the Fermi Gamma-ray Burst Monitor with a
1-sec peak photon flux in the 8-1000 keV band of 40.9 +/- 0.5
ph/s/cm^2 and was sufficiently bright to trigger a spacecraft
repointing maneuver. The burst occurred 55.7 degrees off axis with
respect to the LAT boresight. The subsequent repoint maneuver resulted
in pointed observations starting 200 seconds post trigger and lasting
for approximately 5 hours.

No significant emission was detected in the LAT band during any of the
time intervals in which the burst was in the LAT field of view. We use
a Bayesian method (as described in Abdo et al. 2009: arXiv:0910.4192)
to determine the 95% CL upper limits on the LAT energy flux and
fluence for several time intervals with respect to the GRB trigger
time (02:43:09.32 UT, October 10th 2009):

Prompt Emission (T0 to T0+8.1s):
95% Energy Flux Upper Limit = 1.94e-7 erg/s/cm^2
95% Energy Fluence Upper Limit = 1.57e-06 erg/cm^2

Extended Emission Interval 1 (T0-200s to T0+200s):
95% Energy Flux Upper Limit = 4.35e-9 erg/s/cm^2
95% Energy Fluence Upper Limit = 1.74e-06 erg/cm^2

Extended Emission Interval 2 (T0 to T0+400s):
95% Energy Flux Upper Limit = 4.13e-9 erg/s/cm^2
95% Energy Fluence Upper Limit = 1.65e-066 erg/cm^2

Furthermore, the upper limit on the ratio between the 0.1-300 GeV to
8-1000 keV fluence (HE/LE) for the T0 to T0+8.1s interval is 0.14.

The upper limit results presented above are preliminary. 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: GRB091102A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10129
SUBJECT: GRB 091102: LABOCA/APEX submm observations
DATE:    09/11/03 23:08:08 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (INAF-OAB), A. Lundgren,
C. de Breuck (ESO), A.J. Castro-Tirado, M. Jelinek
(IAA-CSIC) report on behalf of a larger collaboration:

We have observed the field of GRB 091102 (Hoversten et al.,
GCN 10117) with using LABOCA/APEX from Chajnantor
(Chile) at 870 um, under non optimal conditions
(PWV~2.5mm). The observation consisted of 3 hours on target,
with a total integration time of 2.2 hours and mean epoch 14.0
hours after the burst. The r.m.s of the image is 6.3 mJy and
covers the complete BAT error box. In particular, we do not
detect any new source at the location of the XRT position
(Baumgartner et al., GCN 10121).

We acknowledge excellent support from APEX staff, in particular
we thank Francisco Montenegro and Claudio Agurto.


GRB_name: GRB091104A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10130
SUBJECT: GRB 091104: Swift detection of a burst
DATE:    09/11/04 09:08:23 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

P.A. Curran (MSSL-UCL), W. H. Baumgartner (GSFC/UMBC),
A. P. Beardmore (U Leicester), S. Campana (INAF-OAB),
P. A. Evans (U Leicester), C. Guidorzi (U Ferrara),
J. A. Kennea (PSU), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB),
P. T. O'Brien (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL), A. Rowlinson (U Leicester) and M. H. Siegel (PSU)
report on behalf of the Swift Team:

At 08:49:22 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091104 (trigger=374875).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 208.742, +47.398 which is 
   RA(J2000) = 13h 54m 58s
   Dec(J2000) = +47d 23' 55"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is usual for an image trigger, there
is no obvious variation in the immediately available light curve. 

The XRT began observing the field at 08:51:34.2 UT, 131.5 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 208.75600, 47.41126 which
is equivalent to:
   RA(J2000)  = 13h 55m 1.44s
   Dec(J2000) = +47d 24' 40.5"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 58 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.72e+20 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 1.85e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with
the White filter starting 139 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 P.A. Curran (pac AT mssl.ucl.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB091104A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10131
SUBJECT: GRB 091104: Enhanced Swift-XRT position
DATE:    09/11/04 15:56:13 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 677 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 091104, 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 = 208.75624, +47.41054 which is equivalent
to:

RA (J2000): 13h 55m 1.50s
Dec (J2000): +47d 24' 37.9"

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: GRB091102A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10132
SUBJECT: GRB091102 : MOA optical upper limit
DATE:    09/11/04 16:05:21 GMT
FROM:    Kenta Nishimoto at Nagoya U/MOA-II  <nishimo@stelab.nagoya-u.ac.jp>

K. Nishimoto, D. Suzuki, T. Sako, and F. Abe (STE Lab, Nagoya Univ.)
on behalf of the MOA Collabration report:

We searched for an optical afterglow of GRB091102 (Hoversten et al. GCN
10117) starting from 14:57:07.8 UT on 2009 Nov 2 (22.5 minuts after the
burst) with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand.
In a single image of a 60sec exposure with a wideband Red filter (center
wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object within
the error circle of the Swift XRT source position (GCN 10120), except a
star reported by BOOTES-3 (De Ugarte Postigo et al. GCN 10122) and GROND
(R. Filgas et al. GCN 10123), which has I mag=19.15 and the separation
of 1.6 arcsec from the center of the position.
A 5 sigma upper limit is set in the I magnitude at 20.8 mag.

This photometry was done by using the DoPhot and calibrated against the
USNO-B1.0 cataloged stars, and not corrected for the Galactic extinction.


GRB_name: GRB091026A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10133
SUBJECT: GRB091026 : IRSF NIR upper limit
DATE:    09/11/04 16:35:22 GMT
FROM:    Kenta Nishimoto at Nagoya U/MOA-II  <nishimo@stelab.nagoya-u.ac.jp>

K. Nishimoto, T. Sako (Nagoya Univ.) on behalf of the MOA Collaboration,
M. Kurita, T. Nagayama (Nagoya Univ.) on behalf of the IRSF Collabration
report:

We searched for a NIR afterglow of GRB091026 (Markwardt et al., GCN
10081) starting from 18:43:32.3 UT on 2009 Oct 26 (5.5 hours after the
burst) with the SIRIUS on the IRSF 1.4m telescope at SAAO in South Africa.
In images of a 300sec exposure with J, H and Ks filter, we did not find
any object within the error circle of the Swift XRT source position
(Evans. et al., GCN 10084).

A 5 sigma upper limits are the followings.

J > 18.35
H > 17.39
K > 16.70

This photometry was done by using the DoPhot and calibrated against the
2MASS cataloged stars


GRB_name: GRB091104A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10134
SUBJECT: GRB 091104: Swift/UVOT Upper Limits
DATE:    09/11/04 17:13:20 GMT
FROM:    Peter Curran at MSSL  <pac@mssl.ucl.ac.uk>

P.A. Curran (MSSL-UCL) reports on behalf of the Swift/UVOT team:


The Swift/UVOT began settled observations of the field of GRB 091104 139s 
after the BAT trigger (Curran et al., GCN 10130). No optical afterglow 
consistent with the enhanched XRT position (Osborne et al., GCN 10131) is 
detected in the initial UVOT exposures. Preliminary 3-sigma upper limits 
using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for 
the finding charts (FC) and subsequent exposures are:


Filter    T_start(s)   T_stop(s)    Exp(s)    Mag
-------------------------------------------------------
white     139          289          147       >20.56 (FC)
u         297          547          246       >19.69 (FC)
white     139          993          301       >20.84
v         628          6155         87        >18.53
b         553          746          39        >18.88
u         297          721          265       >19.74
w1        677          870          39        >18.45
m2        652          845          39        >18.26
w2        776          4636         151       >19.71

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


GRB_name: GRB091104A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10135
SUBJECT: GRB 091104: Swift XRT Refined Analysis
DATE:    09/11/04 20:04:49 GMT
FROM:    Antonia Rowlinson at U.of Leicester  <bar7@star.le.ac.uk>

A. Rowlinson (U Leicester) and P.A. Curran (MSSL-UCL) report on behalf
of the Swift-XRT team:

We have analysed 2.7 ks of XRT data for GRB 091104 (Curran et al. GCN
Circ. 10130), from 137 s to 16.5 ks after the BAT trigger. The data
comprise 162 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. The enhanced XRT position for this burst was given
by Osborne et al. (GCN. Circ 10131). The light curve can be modelled
with a series of power-law decays. The initial decay index is alpha=0.55
(+0.24, -0.27). At T+226.54 s the decay steepens to an alpha of 4.86
(+0.35, -0.29) before breaking again at T+524.02 s to a final decay with
index alpha=1.48 (+1.19, -0.29).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.298 (+0.103, -0.096). The
best-fitting absorption column is 1.09 (+0.20, -0.19) x 10^21 cm^-2, in
excess of the Galactic value of 1.7 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 2.31 (+0.22, -0.15)
and a best-fitting absorption column consistent with the Galactic value.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 3.1 x 10^-11 (3.4 x 10^-11) erg cm^-2
count^-1.

If the light curve continues to decay with a power-law decay index of
1.48, the count rate at T+24 hours will be 1.9 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.9 x
10^-11 (6.5 x 10^-11) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00374875.
This circular is an official product of the Swift-XRT team.


GRB_name: GRB091104A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10136
SUBJECT: GRB 091104: Swift-BAT refined analysis
DATE:    09/11/04 20:26:56 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
P.A. Curran (MSSL-UCL), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+903 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091104 (trigger #374875)
(Curran, et al., GCN Circ. 10130).  The BAT ground-calculated position is
RA, Dec = 208.723, 47.391 deg, which is 
   RA(J2000)  =  13h 54m 53.6s 
   Dec(J2000) = +47d 23' 25.8" 
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 82%.
 
The mask-weighted light curve shows a sharp rise at ~T+2, a rather flat top,
and ending at ~T+120 sec.  T90 (15-350 keV) is 99.3 +- 20 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-1.5 to T+120.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.74 +- 0.24.  The fluence in the 15-150 keV band is 7.7 +- 1.2 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+83.34 sec in the 15-150 keV band
is 0.4 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/374875/BA/


GRB_name: GRB091029A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10137
SUBJECT: GRB 091029: Observations from Stardome Observatory
DATE:    09/11/05 08:44:38 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

G. W. Christie (Stardome Obs., New Zealand),
S. Dong (IAS, Princeton), A. de Ugarte
Postigo (INAF-OAB, Italy) and T. Natusch
(Stardome Obs., New Zealand) report:

We observed the field of GRB 091029 (Swift
trigger 372210, Grupe et al. GCN 10097) with
the Stardome 0.4m telescope located in
Auckland (New Zealand) starting at 07:55UT,
3.90 hours after BAT trigger. We used a SG530
filter that transmits wavelengths above 5300
Angstroms and a SBIG ST-L-6303E CCD (KAF-6303E
detector).

A nearly continuous series of 300s images was
taken until 16:30UT under mostly clear
conditions (seeing: 1.6-2.5"). These were
co-added making 15 stacks of 6 images (1800s
exposure each).

The fading afterglow (Filgas et al., GCN 10098;
LaCluyze et al., GCN 10099; de Ugarte Postigo
et al., GCN 10104; Marshall et al. GCN 10108)
was clearly detected in all images over the
observing period, yielding the following psf
photometry(DOPHOT):

UT (mid)    delT      R1      Err (statistical)
29.32713    3.901    19.34    0.09
29.34906    4.428    19.32    0.08
29.37120    4.959    19.43    0.08
29.39311    5.485    19.46    0.08
29.41503    6.011    19.67    0.08
29.43360    6.456    19.57    0.08
29.45862    7.057    19.73    0.08
29.50946    8.277    19.93    0.12
29.53164    8.809    19.94    0.09
29.56044    9.501    20.16    0.09
29.59390   10.304    20.21    0.11
29.61620   10.839    20.21    0.13
29.63853   11.375    20.36    0.16
29.66081   11.910    20.41    0.17

where delT is the mid-exposure time in hours
since trigger. Photometric calibration was
done against USNOB1 0340-0030262 RA (J2000):
04h 00m 38.61s,  DEC( J2000): -55d 55' 37.3"
assuming R1=16.40.

The mean power-law index over this interval
was -0.94 (+/-0.05). Astrometry of the images
gave the afterglow position (UCAC2) as:

RA (J2000) = 04h 00m 42.62s
DEC (J2000) = -55d 57' 20.2"

with an uncertainty of 0.18"

This position is in agreement with Marshall et
al. (GCN 10108) and Grupe et al. (GCN 10097).


GRB_name: GRB091109A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10138
SUBJECT: GRB 091109: Swift detection of a burst with optical afterglow
DATE:    09/11/09 05:11:55 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), N. Gehrels (NASA/GSFC),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
C. B. Markwardt (CRESST/GSFC/UMD), K. L. Page (U Leicester),
D. M. Palmer (LANL), M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC)
and L. Vetere (PSU) report on behalf of the Swift Team:

At 04:57:43 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091109 (trigger=375246).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 309.265, -44.176 which is 
   RA(J2000) = 20h 37m 04s
   Dec(J2000) = -44d 10' 34"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a spiky
structure with a duration of about 25 sec.  The peak count rate
was ~800 counts/sec (15-350 keV), at ~20 sec after the trigger. 

The XRT began observing the field at 05:00:14.1 UT, 150.7 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source located at RA, Dec 309.25854, -44.15853 which
is equivalent to:
   RA(J2000)  = 20h 37m 2.05s
   Dec(J2000) = -44d 09' 30.7"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 65 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 (2.99e+20
cm^-2, Kalberla et al. 2005), with an excess column of 3 (+1.84/-1.63)
x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 155 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 20:37:01.81 = 309.25755
  DEC(J2000) = -44:09:29.6  = -44.15821
with a 90%-confidence error radius of about 0.69 arc sec. This position is 2.7
arc sec. from the center of the XRT error circle. The estimated magnitude is
19.92 with a 1-sigma error of about 0.18. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.03. 

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


GRB_name: GRB091109A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10139
SUBJECT: GRB091109: REM detection of the NIR afterglow
DATE:    09/11/09 06:14:55 GMT
FROM:    Angelo Antonelli at Obs. Astro. di Roma  <a.antonelli@oa-roma.inaf.it>

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

 "The robotic 60-cm REM telescope located at La Silla (Chile) observed
automatically the field of the GRB 091109 (Oates et al. GCN10138) starting about
77 s after the burst. We detect a faint object in the XRT error circle in our
first H-band images at H~14.8 at coordinates: RA(J2000) 20:37:02.2; Dec(J2000)
-44:09:30.4 with 1 arcsec error.

This message can be cited"



-------------------------------------------------
This mail sent through IMP: http://horde.org/imp/


GRB_name: GRB091109A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10140
SUBJECT: GRB 091109: Enhanced Swift-XRT position
DATE:    09/11/09 09:42:18 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 3018 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 091109, 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 = 309.25767, -44.15872 which is equivalent
to:

RA (J2000): 20h 37m 1.84s
Dec (J2000): -44d 09' 31.4"

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

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB091109A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10141
SUBJECT: GRB 091109: Swift-BAT refined analysis
DATE:    09/11/09 11:34:40 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
C. B. Markwardt (GSFC/UMD), S. R. Oates (UCL-MSSL), D. M. Palmer (LANL),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091109 (trigger #375246)
(Oates, et al., GCN Circ. 10138).  The BAT ground-calculated position is
RA, Dec = 309.252, -44.177 deg, which is 
   RA(J2000)  =  20h 37m 00.5s 
   Dec(J2000) = -44d 10' 36.0" 
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 19%.
 
The mask-weighted light curve shows a couple overlapping peaks. The first starts
at ~T-15 sec, peaks at ~T+10 sec.  The second (weaker) peaks at ~T+40 sec and
ends at ~T+60 sec.  T90 (15-350 keV) is 48 +- 17 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-0.8 to T+51.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.31 +- 0.25.  The fluence in the 15-150 keV band is 1.6 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+8.20 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/375246/BA/


GRB_name: GRB091109A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10142
SUBJECT: GRB 091109: Faulkes Telescope South observations
DATE:    09/11/09 12:12:49 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

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

On 2009 November 9 at 09:26:10 UT the 2-m Faulkes Telescope South
began observing GRB 091109 (Oates et al., GCN Circ. 10138) using
the R and i' filters.

We detect the UVOT optical afterglow candidate at a position
consistent with that reported by Oates et al. (but not consistent
with the object reported by REM Antonelli et al., GCN Circ. 10139),
with the following magnitudes:

Mid Time from GRB   Total Exp  Filter   Magnitude
(hours)             (s)
-----------------------------------------------------
4.74                600         i'      21.7  +- 0.3
5.29                600         R       21.95 +- 0.25
-----------------------------------------------------

Magnitudes have been calibrated from the nearby USNOB-1 star
20:37:02.508, -44:09:33.68, using R2=17.52 and I=17.61.


GRB_name: GRB091109A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10143
SUBJECT: GRB 091109: Swift/UVOT observations
DATE:    09/11/09 12:24:27 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

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

The Swift/UVOT began observerving the field of GRB 091109 156s
after the BAT trigger (Oates et al., GCN Circ. 10138). We detect the
optical afterglow in the white filter only, which faded rapidly.
The refined UVOT position is:

     RA (J2000)  20:37:01.80
    Dec (J2000) -44: 9:29.6

with an estimated uncertainty of 0.7 arcsec (radius, 90% confidence).
This position is consistent with the XRT refined position (Beardmore
et al., GCN Circ 10140).

Preliminary magnitudes and the 3 sigma upper limits are reported below.

Filter    T_start(s)  T_stop(s)  Exposure      Mag  Err
###########################################################
white        156        306         147     19.88 +\- 0.14
white      5371       5571        197        > 21.26
v      4345       5981        393        > 19.94
b      5166       5365        197        > 20.49
u      314        6572        615        > 20.97
uvw1      4755       6392        393        > 20.59
uvm2      4550       6186        393        > 20.46
uvw2      4140       5777        393        > 20.68
###########################################################

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.03 mag (Schlegel et al.,
1998, ApJS, 500, 525).  The photometry is on the UVOT photometric system
described in Poole et al. (2008, MNRAS, 383,627).


GRB_name: GRB091109A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10144
SUBJECT: GRB 091109: BOOTES-3 observations
DATE:    09/11/09 13:41:34 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

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

We have observed the field of GRB 091109 (Oates et al. GCN 10138)
using the 0.6 Yock-Allen robotic telescope (BOOTES-3) located in
Bleinheim, New Zealand. Due to bad weather conditions, observations
did not start until 11:03 UT (6.1h after the burst). A combination of  
the
first 30x60s unfiltered exposures does not show any source at the
UVOT postion down to a 3-sigma limiting magnitude of R~20.0,
consistent with the limits given by UVOT (Oates et al. GCN 10143) and
the fainter detection by Faulkes Telescope South (Guidorzi et al. GCN
10142).

Further observations are ongoing.


GRB_name: GRB091109A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10145
SUBJECT: GRB 091109: Swift-XRT refined analysis
DATE:    09/11/09 16:10:35 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A. P. Beardmore (U. Leicester) and S. R. Oates (UCL-MSSL) report on
behalf of the Swift-XRT team:

We have analysed 7.9 ks of Swift-XRT data for GRB 091109 (Oates et al. 
GCN Circ. 10138), from 154 s to 18.1 ks after the BAT trigger. The data
span four orbits, comprising 37 s in Windowed Timing (WT) mode with
the remainder in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Beardmore et al. (GCN. Circ 10140).

The light curve can be modelled by a broken power-law with an initial
decay slope of 2.9 +0.5 -0.4, breaking at T+358 s to a shallower decay
of 0.86 +0.07 -0.08.

A spectrum formed from the PC mode data (from 175 s to 18.1 ks after
the trigger) can be fitted with an absorbed power-law, giving a photon
index of 2.10 +/- 0.19. The best-fitting absorption column is (9.9
+2.1 -4.4) x 10^20 cm^-2, in excess of the Galactic value of 3.0 x
10^20 cm^-2 (Kalberla et al. 2005) in the direction of the burst. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 3.6 x 10^-11 (4.8 x 10^-11) erg cm^-2
count^-1.

If the light curve continues to decay with a power-law decay index of
0.86, the count rate at T+24 hours will be 4.7 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x
10^-13 (2.3 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/00375246.

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


GRB_name: GRB091030A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10146
SUBJECT: GRB 091030: Fermi GBM detection
DATE:    09/11/09 16:25:41 GMT
FROM:    Michael Burgess at UAH  <james.burgess@uah.edu>

J. Michael Burgess (UAH) and Sylvain Guiriec (UAH)
report on behalf of the Fermi GBM Team:

"At 19:52:26.86 UT on 30 October 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091030 (trigger 278625148 / 091030828).


The on-ground calculated location, using the GBM trigger
data, is RA = 41.67, DEC = 21.54 (J2000 degrees,
equivalent to 17h 40m 12, 21d 32'), with an uncertainty
of 1.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 100 degrees.

The GBM light curve consists of 2 bright peaks followed
by 2 dimmer peaks.
with a duration (T90) of about 160 s (8-1000 keV).
The time-averaged spectrum from T0-1.7 s to T0+40 s is
best fit by a Band function with Epeak = 507 +/- 30 keV,
alpha = -0.88 +/- 0.02, and beta = -2.2 +/- 0.1 (castor C-stat 626 for  
478 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(3.03 +/- 0.043) E-5 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+17.54 s in the 8-1000 keV band
is 9.58 +/- 0.23 ph/s/cm^2.

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


GRB_name: GRB091109A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10147
SUBJECT: GRB091109: Correction to GCN 10139
DATE:    09/11/09 19:08:33 GMT
FROM:    Angelo Antonelli at Obs. Astro. di Roma  <a.antonelli@oa-roma.inaf.it>

L.A. Antonelli, S. Covino, P. D'Avanzo, report on behalf of the REM team:

"We have to correct the position of the object reported in our previous GCN
10139: due to a typo the R.A. position of the putative NIR afterglow of
GRB091109 reported is RA(J2000) 20:37:02.02 instead of RA(J2000) 20:37:02.2.

However, we note that the correct position is still about 2" far away from the
UVOT position (Oates, GCN 10143). The observed source in the REM H band early
images is very faint and close to the detection limit of our images. So due to
the misplacement with the UVOT position the observed object may be a background
fluctuation not related to GRB091109. A detailed analysis is in progress."




-------------------------------------------------
This mail sent through IMP: http://horde.org/imp/


GRB_name: GRB091109B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10148
SUBJECT: GRB 091109B: Swift detection of a short burst
DATE:    09/11/09 22:10:18 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), C. B. Markwardt (CRESST/GSFC/UMD),
F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL),
A. Rowlinson (U Leicester), T. Sakamoto (NASA/UMBC),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC), M. A. Stark (PSU),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 21:49:03 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091109B (trigger=375409).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 112.717, -54.080 which is 
   RA(J2000)  =  07h 30m 52s
   Dec(J2000) = -54d 04' 48"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single spike
with a duration of about 0.4 sec.  The peak count rate
was ~30,000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 21:50:21.1 UT, 78.1 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 112.7349, -54.0896
which is equivalent to:
   RA(J2000)  = 07h 30m 56.39s
   Dec(J2000) = -54d 05' 22.7"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 51 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
9.23e+20 cm^-2 (Kalberla et al. 2005). 

UVOT took a finding chart exposure of 250 seconds with the U filter starting
296 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the
XRT error circle. The 3-sigma upper limit is 20.3 mag. The
coverage of the XRT error circle by the 8'x8' region for the list of sources
generated on-board is uncertain because the large number of sources filled the
available telemetry. No correction has been made for the expected extinction
corresponding to E(B-V) of 0.17. 

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


GRB_name: GRB091109B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10149
SUBJECT: GRB 091109B: ROTSE-III Optical Limits 
DATE:    09/11/09 22:25:08 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

B. E. Schaefer (Louisiana State), E.S. Rykoff (UCSB), T. Guver (U 
Arizona), H. Flewelling (IfA/Hawaii), S. B. Pandey (U Mich), report on 
behalf of the ROTSE collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, 
responded to GRB 091109B (Swift trigger 375409; S. R. Oates et al., GCN 
10148), producing images beginning 9.4 s after the GCN notice time. An 
automated response took the first image at 21:49:24.5 UT, 21.6 s after the 
burst, under excellent conditions. We took 10 5-sec, 10 20-sec and 10 
60-sec exposures. These unfiltered images are calibrated relative to USNO 
A2.0 (R). Imaging is on going.

Comparison to the DSS (second epoch) reveals no new sources within the 
3-sigma Swift/BAT error circle or the XRT error circle, for both single 
images and coadding into sets of 10; the field is not crowded. Individual 
images have limiting magnitudes ranging from 15.9-17.0; we set the 
following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
21:49:24.5   21:49:29.5         5     16.0           21.6       N
21:49:24.4   21:50:40.5        76     16.9           21.5       Y


GRB_name: GRB091109B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10150
SUBJECT: GRB 091109B: Optical limits from Watcher
DATE:    09/11/09 23:47:07 GMT
FROM:    Petr Kubanek at AIO  <petr@lascaux.asu.cas.cz>

M. JelÄ‚Â­nek (IAA-CSIC), A. de Ugarte Postigo (INAF-OAB), R. Felletti, L.
Hanlon (UCD Dublin), H. Van Heerden (UOVS, Bloemfontein), P. KubÄ‚Ä„nek
(IPL UV, IAA-CSIC) reports on behalf of a large collaboration:

Watcher telescope, located at Boyden Observatory, South Africa,
observed autonomously GRB 091109B (S. R. Oates et al., GCN 10148). We
obtained a set of 5s exposures in clear filter, starting 78s after the
GRB (65s after the notice). We see no new sources in the XRT error box
down to the single-image limiting magnitude of 16.5. Coaddition of
first 120s (mean exposure time 153s after the GRB) of imaging data
improves this limit to ~17.7 calibrated against field USNO-A2.0 R-band
stars. Those results are consistent with ROTSE-III non-detection
(Schaefer et al. GCN 10149).

We note that there is a R~15.3 galaxy 8" North-West of the XRT position,
posibly the host of this short GRB.

Further observations are ongoing. This message can be quoted.


GRB_name: GRB091109B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10151
SUBJECT: GRB 091109B: Enhanced Swift-XRT position
DATE:    09/11/10 03:10:55 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 1173 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 091109B, 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 = 112.73603, -54.08983 which is equivalent
to:

RA (J2000): 07h 30m 56.65s
Dec (J2000): -54d 05' 23.4"

with an uncertainty of 2.8 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: GRB091109B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10152
SUBJECT: GRB 091109B: Swift-BAT refined analysis
DATE:    09/11/10 03:19:30 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

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

Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091109B (trigger #375409)
(Oates, et al., GCN Circ. 10148).  The BAT ground-calculated position is
RA, Dec = 112.750, -54.092 deg which is
    RA(J2000)  =  07h 30m 59.9s
    Dec(J2000) = -54d 05' 30.6"
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 76%.

The mask-weighted light curve shows a single symmetrical peak of duration 0.32 
seconds.  There is no sign of extended emission.
T90 (15-350 keV) is 0.3 +- 0.03 sec (estimated error including systematics).

The time-averaged spectrum from T-0.0 to T+0.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
0.71 +- 0.13.  The fluence in the 15-150 keV band is 1.9 +- 0.2 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.33 sec in the 15-150 keV band
is 5.4 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/375409/BA/

[GCN OPS NOTE(09nov09):  Per author's request, the "B" was added to the
GRB name and the reference was filled in.]


GRB_name: GRB091109B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10153
SUBJECT: GRB 091109b:  Magellan Observations
DATE:    09/11/10 05:28:28 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard), K. Covey (Cornell), A. A. West, J. M. Andersen 
(BU), and M. McDonald (U. Maryland, College Park) report:

"We observed the XRT error circle (GCN #10151) of the short GRB 091109b 
(GCN #10152) with IMACS on the Magellan/Baade 6.5-m telescope starting 
on 2009 Nov. 10.167 UT (6.2 hours after the burst).  In a 1200-sec 
stacked R-band image we find no optical sources within the XRT error
circle to a 3-sigma limit of R~23 mag in comparison to several nearby 
stars in the USNO-B catalog.  We further note that the object claimed to 
be a galaxy north-west of the XRT position (GCN #10150) appears to be 
resolved into two point sources in our image (with a seeing of about
1.1 arcsec)."


GRB_name: GRB091109B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10154
SUBJECT: GRB 091109B: VLT observations
DATE:    09/11/10 05:33:34 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (Warwick), N.R. Tanvir (Leicester),  J. Hjorth, D. Malesani (DARK/NBI),
A. de Ugarte Postigo, P. D'Avanzo (INAF-OAB) report on behalf of a larger collaboration:

We observed the location of the short GRB 091109B (Oates et al. GCNC 10148), with
the VLT/FORS2. Observations began at 03:34 UT, approximately 5.7 hours after the burst.
Within the X-ray localisation (Evans et al. GCNC 10151)  we identify a faint source 
(Source A) at:

RA: 07:30:56.61
Dec: -54:05:22.85

We also identify a second, fainter source (Source B) just outside the X-ray localisation, 
at:

RA: 07:30:56.46
Dec: -54:05:25.56

Both positions have errors of ~0.5" in each axis.

Source A has R~25, and appears pointlike. At this stage we cannot make any claim of 
variability in either source A or B, although further observation are planned.

Additionally, we note that the apparently extended object to the NW is actually a blend
of two stars, and a possible galaxy, rather than a single object, and hence its relation
to GRB 091109B is currently unclear.

We thank P. Lyman and the staff of VLT for their assistance with these observations.


GRB_name: GRB091109B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10155
SUBJECT: GRB 091109B: Swift-XRT Team refined analysis 
DATE:    09/11/10 07:33:26 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page (U. Leicester) and S.R. Oates (UCL-MSSL) report on behalf of 
the Swift-XRT team:

We have analysed 9.7 ks of XRT data for GRB 091109B (Oates et al. GCN 
Circ. 10148), from 86 s to 22.9 ks after the BAT trigger. The data are 
entirely in Photon Counting (PC) mode. The enhanced XRT position for this 
burst was given by Evans et al. (GCN. Circ 10151).

The light curve can be modelled with a power-law decay with a decay index 
of alpha=0.62 (+0.11, -0.10). Although there is some evidence that there 
may be a steep, shallow, normal trend in the light-curve, as is often 
seen, there are not enough data points to warrant such additional 
modelling at this time.

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, -0.4). The 
best-fitting absorption column is 1.2 (+1.4, -0.1) x 10^21 cm^-2, in 
excess of the Galactic value of 9.2 x 10^20 cm^-2 (Kalberla et al. 2005). 
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor 
deduced from this spectrum is 3.8 x 10^-11 (5.3 x 10^-11) erg cm^-2 
count^-1.

If the light curve continues to decay with a power-law decay index of 
0.62, the count rate at T+24 hours will be 2.4 x 10^-3 count s^-1, 
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.1 x 10^-14 
(1.2 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/00375409.

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


GRB_name: GRB091109B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10156
SUBJECT: GRB 091109B: VLT afterglow confirmation
DATE:    09/11/10 10:00:29 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@astro.ku.dk>

D. Malesani (DARK/NBI), A. de Ugarte Postigo (INAF/OABr), A. J. Levan 
(Univ. Warwick), N. R. Tanvir (Univ. Leicester), J. Hjorth (DARK/NBI), 
P. D'Avanzo (INAF/Brera), report on behalf of a larger collaboration:

Following the observations of GRB 091109B (Oates et al., GCN 10148) with 
the VLT reported by Levan et al. (GCN 10154), we obtained a further 
epoch of R-band imaging with mean time Nov 10.33 UT (10.22 hr after the 
burst), using the same instrument and configuration.

Source "A" by Levan et al. (GCN 10154) is still detected, and decayed by 
1.0+-0.3 mag during this time interval, implying a decay index of alpha 
= 1.7+-0.5. We hence conclude that the source is indeed the afterglow of 
GRB 091109B.

We acknowledge excellent support from the ESO staff at Paranal, in 
particular Alain Smette and Paul Lynam.


GRB_name: GRB091109B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10157
SUBJECT: GRB 091109B: Swift/UVOT Upper Limits
DATE:    09/11/10 12:35:35 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

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

The Swift/UVOT began settled observations of the field of
GRB 091109B 84s after the BAT trigger (Oates et al., GCN 10148).
We do not detect any source at the enhanced Swift XRT position
(Evans et al. GCN 10151) and at the location of source A detected
by the VLT (Levan et al. GCN 10154, Malesani et al. GCN 10156)

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

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white (FC)  84     234       147         > 21.25
u     (FC)  296    546       246         > 20.29
white       577    18629     1313        > 22.09
v           627    11274     1172        > 20.96
b           553    17890     1337        > 21.78
u           701    23171     1761        > 21.61
uvw1        677    22710     1988        > 21.44
uvm2        652    12179     1160        > 20.87
uvw2        603    7050      471         > 20.52
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.17 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).


GRB_name: GRB091109A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10158
SUBJECT: GRB 091109A: GROND and VLT observations
DATE:    09/11/10 14:59:13 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

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


GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m ESO/MPI 
telescope at La Silla Observatory (Chile), observed the field of GRB 
091109A (Oates et al., GCN #10138) simultaneously in the g'r'i'z'JHK bands.

Observations were done under clear sky conditions, starting on Nov 10 at 
00:07 UTC, 19.1 h after the burst and lasted for 1.8 hours.

In stacked images corresponding to a total integration time of 60 min in 
JHK and 75 min in g'r'i'z', we detect the optical afterglow (Oates et 
al., GCN #10138, Guidorzi et. al, GCN #10142) in the g'r'i'z' bands and 
obtain the following preliminary magnitudes and upper limits (all in the 
AB system):

g' = 24.5 +/- 0.1
r' = 23.6 +/- 0.1
i' = 23.4 +/- 0.1
z' = 23.3 +/- 0.2
J > 22.2
H > 21.8
K > 21.2

which were derived using the GROND zero points and 2MASS catalog field 
stars as reference. No correction has been made for the expected 
extinction corresponding to a reddening of E(B-V) = 0.03 mag in the 
direction of the burst (Schlegel et al. 1998).

Associating the blue g'-r' color with Lyman-alpha absorption in the host 
of the GRB, we obtain a photometric redshift of z = 3.5 +/- 0.4 assuming 
no intrinsic dust.

In addition, we triggered VLT/FORS2 spectroscopy, that started Nov 10 at 
02:23 UTC, 21.5 h post-burst. Two integrations of 1800 s each at a mean 
airmass of 2.1 were obtained using the 600RI grism that covers the 
wavelength range from 5300 to 8700 A.  In the low S/N spectrum we find a 
tentative ~60A EW broad absorption feature around a wavelength of 5700A. 
If associated with Lyman-alpha absorption, the corresponding redshift of 
~3.5 would be in agreement with the GROND photo-z.

We note, however, that all observations are also consistent with a host 
galaxy at a redshift of z ~ 0.44. Given the absence of information about 
a possible host galaxy contribution we cannot distinguish these two 
possibilities at this point.

We thank A. Smette and P. Lynam at Paranal for excellent support.


GRB_name: GRB091111A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10159
SUBJECT: GRB 091111: a faint long GRB detected with INTEGRAL
DATE:    09/11/12 10:43:53 GMT
FROM:    Diego Gotz at CEA  <diego.gotz@cea.fr>

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

a long faint and soft gamma-ray burst has been detected by the  
INTEGRAL Burst Alert System in IBIS/ISGRI data on November 11 2009.  
Due to its faintness no automatic alert has been issued and the GRB  
has been identified through the routine off-line analysis of the low  
significance triggers. The GRB starts at 15:21:59 U.T. and lasts for  
about 100 s.

The GRB coordinates (J2000) are

R.A. : 137.8133 [degrees] ,  Dec.: -45.9093 [degrees]

with a 90% c.l. radius unercainty of 2.5 arcmin.

Even if no known X-ray source is present in the IBAS error circle, we  
note that the low galactic latitude of the object and its soft X-ray  
spectrum may indicate also a Galactic transient origin.
The light curve of the GRB will be posted at http://ibas.iasf-milano.inaf.it/IBAS_Results.html

This message can be cited.

[GCN OPS NOTE(12nov09):  Per author's request, CB was added
to the author list.]


GRB_name: GRB091111A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10160
SUBJECT: GRB 091111: BOOTES-3 observations
DATE:    09/11/12 14:22:09 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

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

"We have observed the field of the INTEGRAL GRB  091111 (Gotz et al.  
GCNC 10159) using the 0.6m Yock-Allen robotic telescope (BOOTES-3)  
located in Bleinheim, New  Zealand.  The observations were carried out  
between Nov. 12.45208 UT and 12.47379 UT, with a total exposure time  
of 88 min (starting 19.5 h after the burst).  Visual comparison with  
the DSS does not show any new source in our combined unfiltered image  
of the INTEGRAL error box down a limiting magnitude (3 sigma) of R~19.6.

Further observations are ongoing."


GRB_name: GRB091111A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10161
SUBJECT: GRB 091111: BOOTES-3 contemporaneous imaging
DATE:    09/11/12 14:53:11 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A.  de  Ugarte  Postigo (INAF-OAB), J.  Gorosabel,  A.J. Castro-Tirado,
M.  Jelinek (IAA-CSIC), P.  Kubanek (IPL UV, IAA-CSIC) and W.H. Allen
(Vintage  Lane Obs.), on behalf of a larger collaboration, report:

"During regular monitoring, the all-sky camera located at BOOTES-3
observatory in Blenheim, New Zealand observed the field of the
INTEGRAL GRB 091111 (Gotz et al. GCN 10159) before during and
after the burst onset. We have examined the images obtained at the
time of the GRB and we do not detect any new source within the
INTEGRAL error box. In the following table we give time ranges and
3-sigma limiting magnitudes of the observations that overlap with the
gamma-ray emission.

T-T0(start-->end)  Lim
=================
-31s --> +5s           9.3
+24s --> +60s        9.3
+79 --> +115s        9.3

This GCNC can be quoted."


GRB_name: GRB091112A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10162
SUBJECT: GRB 091112: Swift detection of a possible burst
DATE:    09/11/12 17:57:24 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

V. Mangano (INAF-IASFPA), W. H. Baumgartner (GSFC/UMBC),
S. Campana (INAF-OAB), P.A. Curran (MSSL-UCL),
C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC),
E. A. Hoversten (PSU), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), J. Mao (INAF-OAB),
R. Margutti (Univ Bicocca&OAB), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU),
M. Stamatikos (OSU/NASA/GSFC), M. A. Stark (PSU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 17:41:21 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091112 (trigger=375659).  Swift could not slew to the
burst due to the Sun constraint.  The BAT on-board calculated location is 
RA, Dec 257.728, -36.715 which is 
   RA(J2000) = 17h 10m 55s
   Dec(J2000) = -36d 42' 53"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a symmetrical peak
structure with a duration of about 20 sec.  The peak count rate
was ~2000 counts/sec (15-350 keV), at ~5 sec after the trigger. 

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

Because this location is about 10 degrees from the Galactic center,
we cannot rule out the possibility of this being a Galactic source. 
However, there are no known Galactic sources at this location. 

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


GRB_name: GRB091031A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10163
SUBJECT: GRB 091031: Fermi LAT detection of a faint burst
DATE:    09/11/12 22:41:27 GMT
FROM:    Francesco de Palma at U of INFN Bari  <francesco.depalma@ba.infn.it>

F. de Palma (University and INFN Bari), N. Omodei (INFN Pisa), Julie 
McEnery (NASA/GSFC) and
V. Vasileiou (NASA GSFC/UMBC) report on behalf of the Fermi LAT team:

At 12:00:28 (UT) on 31 October 2009 , the Fermi Large Area Telescope 
(LAT) detected gamma rays
from the long GRB 091031, which was triggered and located by the Fermi 
Gamma-ray Burst Monitor
(GBM) (trigger 278683230 / 091031500,GCN 10115). The angle of the GBM 
best position (RA, Dec=
70.58, -59.08) with respect to the LAT boresight was ~22 degrees at the 
time of the trigger,
which is well inside our field of view.

The Fermi LAT events after the GBM trigger are spatially and temporally 
correlated with the
emission measured by GBM. In the time interval T0-T0+100s using 
likelihood methods
on photons above 100 MeV this burst has a significance of more than 3 
sigma; using counting
methods the significance is well over 6 sigma in the full energy band 
(20 MeV - 300 GeV).
More than 30 photons above 100 Mev and 2 photons above 1 GeV were 
observed in the same
time interval in an energy dependent ROI centered on the GBM position.
The best LAT on-ground localization is found to be (RA, Dec = 71.7, 
-57.5) with a 90%
containment radius of 0.3 deg (statistical; 68% containment radius: 0.2 
deg, preliminary
systematic error is less than 0.1 deg) which is consistent with the GBM 
localization.

Further analysis is ongoing.

The point of contact for this burst is
Francesco de Palma : francesco.depalma@ba.infn.it

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

This message can be cited.


GRB_name: GRB091112A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10164
SUBJECT: GRB 091112: Fermi GBM observation
DATE:    09/11/13 00:30:38 GMT
FROM:    Michael S. Briggs at UAH and MSFC  <michael.briggs@nasa.gov>

M. S. Briggs (UAH) reports on behalf of the Fermi GBM Team:

"At 17:41:15.82 UT on 12 Nov 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091112 (trigger 279740477 / 091112.737),
which was also detected by the SWIFT-BAT (V. Mangano et al., GCN 10162)
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 82 degrees.

The GBM light curve consists primarily of a broad peak, and
has a duration of about 40 seconds.  
 
The time-averaged spectrum from T0-0.512 s to T0+24.064 s is
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.13 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 750 +/- 120 keV.
C-Stat = 717 for 483 degrees of freedom.

The event fluence (10-1000 keV) in this time interval is
(9.7 +/- 0.3)E-6 erg/cm^2.

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


GRB_name: GRB091112A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10165
SUBJECT: GRB 091112: Swift-BAT refined analysis
DATE:    09/11/13 04:20:04 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), V. Mangano (INAF-IASFPA), C. B. Markwardt (GSFC/UMD),
A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+483 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091112 (trigger #375659)
(Mangano, et al., GCN Circ. 10162).  The BAT ground-calculated position is
RA, Dec = 257.751, -36.729 deg, which is 
   RA(J2000)  =  17h 11m 00.2s 
   Dec(J2000) = -36d 43' 43.4" 
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 40%.
 
The mask-weighted light curve shows a roughly symmetric peak starting
at ~T-15 sec, peaking at ~T+2 sec, and ending at ~T+40 sec.
T90 (15-350 keV) is 17 +- 4 sec (estimated error including systematics).
 
The time-averaged spectrum from T-10.0 to T+14.7 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.03 +- 0.14.  The fluence in the 15-150 keV band is 2.1 +- 0.4 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.56 sec in the 15-150 keV band
is 1.9 +- 0.5 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/375659/BA/


GRB_name: GRB091031A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10166
SUBJECT: Konus-Wind and Konus-RF observations of GRB 091031
DATE:    09/11/13 12:14:19 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 091031 (Fermi-GBM trigger 278683230/091031500,
McBreen and Chaplin, 10115) localized by Fermi-LAT
(de Palma et al., GCN 10163) triggered
Konus-Wind at T0=43232.687s UT (12:00:32.687) and
Konus-RF onboard Coronas-Photon s/c at T0=43230.291s UT (12:00:30.291).

The burst light curve shows a complex structure with a total
duration of ~40 s. The Konus-Wind light curve of this GRB
is available at http://www.ioffe.ru/LEA/GRBs/GRB091031_T43232/

As observed by Konus-Wind the burst had a fluence
of (1.94  0.2)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0 + 4.608s
of (2.74  0.35)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst (from T0 to T0+41.216 s)
is well fitted in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which:
alpha = 0.93 (-0.08, +0.09), and
Epeak = 477 (-91, +138)  keV, Chi2 = 31/58 dof.

Fitting by a GRB (Band) model yiels the same alpha and Epeak
values with high energy spectral index beta of -9.4 (<-2.4)

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


GRB_name: GRB091111A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10167
SUBJECT: GRB091111: Swift XRT refined analysis
DATE:    09/11/13 14:19:06 GMT
FROM:    Vanessa Mangano at INAF-IASFPA  <vanessa@ifc.inaf.it>

V. Mangano, B. Sbarufatti (INAF-IASF PA),
H. A. Krimm (CRESST/GSFC/USRA) and D. M. Palmer (LANL)
report on behalf of the Swift-XRT team:

The INTEGRAL burst GRB091111 (Gotz et al. GCN Circ. 10159)
has been observed by Swift on 2009 11 12 with a 5 ks ToO started
at 19:00 UT (trigger 020120).
We have analysed 5.4 ks of XRT data in PC mode, from 100361 s
to 115.3 ks after the INTEGRAL trigger.

An X-ray source is detected at
RA, Dec 137.82427, -45.92541 which is equivalent to:
   RA(J2000)  = 09h 11m 17.82s
   Dec(J2000) = -45d 55' 31.5"
with an uncertainty of 5.1 arcseconds (radius, 90% containment).

The light curve is probably decaying but more data are needed
to estimate the decay slope.

A spectrum formed from the PC mode data (30 counts within a
circular region of 15 pixel radius) can be fitted with an absorbed
power-law with a photon spectral index of 2.5 (+5, -3.4)
The best-fitting absorption column is < 5 x 10^22 cm-2, consistent
with the Galactic value of 6.2 x 10^21 cm-2 (Kalberla et al.
2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 7.0 x 10^-11 (2.7 x 10^-10) erg
cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020120.

At the time of GRB 091111, the Swift/BAT was active, sensitive and pointing
such that the burst was in the BAT field of view with 25% mask coding.
There is no count rate increase detected in any of the four BAT energy bands

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

[GCN OPS NOTE(30dec12): In response to S.Mereghetti's communication,
this Subject-line was changed from "09111" to "091111".] 


GRB_name: GRB091109B
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10168
SUBJECT: GRB 091109B: Suzaku WAM observation of the prompt emission
DATE:    09/11/14 09:30:39 GMT
FROM:    Masanori Ohno at ISAS/JAXA  <ohno@astro.isas.jaxa.jp>

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


The short GRB 091109B (Swift/BAT trigger #375409 ; Oates et al., GCN  
10148)
triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers an
  energy range of 50 keV - 5 MeV at 2009-11-09 21:49:02.83 UT (=T0).

The observed light curve shows a single peak starting at T0+0.3s, ending
  at T0+0.6s with a duration (T90) of about 0.19 seconds.
The fluence in 100 - 1000 keV was 9.98(-3.69,+0.72) x 10^-7 erg/cm^2.
  The 1-s peak flux measured from T0 was 1.75(-0.59,+0.14) photons/ 
cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0s to T0+1s is well fitted by a power-law with exponential cutoff  
model:
   dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
   alpha       0.91(-0.78,+0.42), and
   Epeak       1330(-610,+1120) keV (chi^2/d.o.f. = 24.6/24).

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

The light curves for this burst are available at:

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


GRB_name: GRB091102A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10169
SUBJECT: GRB 091102A: Suzaku WAM observation of the prompt emission
DATE:    09/11/14 13:39:04 GMT
FROM:    Yuji Urata at Nat. Central U.  <urata@astro.ncu.edu.tw>

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

"The GRB 091102A (Swift-BAT trigger #374598,GCN Circ. 10117; Fermi-GBM
trigger #278865280, GCN Circ. 10126) triggered the Suzaku Wide-band
All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV
on 2009-11-02 14:34:37.863 UT (=T0).

The observed light curve shows a two-peaked structure, starting at
T0-0.5 s and ending at T0+7.5 s, with a total duration (T90) of 6.6 s.          
The fluence in 100 - 1000 keV was 2.31 (-0.61, +0.39) x 10^-6 erg/cm^2.
The 1-s peak flux measured from T0+0.5 s was 1.07 (-0.44, +0.24)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0-0.5 s to T0+7.5 s is well fitted by a single power-law with 
a photon index of 1.56 (-0.22, +0.24) (chi^2/d.o.f. = 15.2/14).

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

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


GRB_name: GRB091112A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10170
SUBJECT: GRB 091112: Suzaku WAM observation of the prompt emission
DATE:    09/11/17 10:15:40 GMT
FROM:    Masanori Ohno at ISAS/JAXA  <ohno@astro.isas.jaxa.jp>

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

The long GRB 091112 (Swift/BAT trigger #375659 ; Palmer et al., GCN  
10165;
Fermi/GBM trigger #279740477 ; Briggs et al., GCN 10164)
triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an
energy range of 50 keV - 5 MeV at 2009-11-12 17:41:16.31 UT (=T0).

The observed light curve shows a multi-peaked structure starting at
T0-4s, ending at T0+16s with a duration (T90) of about 15 seconds.
The fluence in 100-1000 keV was 7.85(-2.91,+0.37)x10^-6  erg/cm2.
The 1-s peak flux measured from T0+7s was 1.25(-0.89,+0.09) photons/ 
cm2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0-4s to T0+16s is well fitted by a power-law with exponential cutoff  
model:
dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha 1.19(-0.76,+0.45), and
Epeak 628(-192,+607)keV (chi2/d.o.f. = 23.9/24).

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

The light curves for this burst are available at:

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


GRB_name: GRB091117A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10171
SUBJECT: GRB 091117A Detected in ground analysis of BAT data and IPN triangulation
DATE:    09/11/18 20:41:05 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

J. R. Cummings (GSFC/CRESST),
V. Pal'shin (Ioffe Inst.),
K. Yamaoka (Aoyama Gakuin U.),
P. Evans (U. Leicester)
on behalf of the Swift-BAT, Konus-Wind, and Suzaku-WAM teams


The Suzaku WAM alerted the IPN to a short hard burst that occurred at
17:44:29 UT on November 17th.  The burst was seen in detector rates
with Suzaku, Konus-Wind, INTEGRAL SPI ACS, and Swift-BAT.  A source
was found in ground analysis of BAT data (trigger 376211) at 12% coding.
The BAT ground position was RA, Dec 30.945, -16.944, which is

RA (J2000) 02h 03m 46.9s
Dec (J2000) -16d 56' 38.0"

with an estimated 90% containment radius of 2.6 arcmin.

As seen in BAT, the burst had a weak precursor at T0, and the main spike
at T+2.7 sec. The precursor was about 0.12 sec and the main spike was
about 0.4 seconds long. The BAT peak count rate was about
700 counts/0.064 sec in the 15-350 keV band.

There is an AGN 2.5 arcmin from this position, 2MASX J02035665-1656585
at z = 0.092.

The BAT position is inside the error box of a triangulation performed
using Konus-Wind, BAT, Suzaku-WAM, and INTEGRAL-SPI-ACS data.

A Swift TOO observation has been requested and approved.


GRB_name: GRB091117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10172
SUBJECT: GRB 091117: OSN I-band observations
DATE:    09/11/18 23:37:29 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

V. Casanova (OSN), A.J. Castro-Tirado (IAA-CSIC), A. de Ugarte Postigo  
(INAF/OAB), J. Gorosabel (IAA-CSIC), report on behalf of a larger  
collaboration:

"We carried out I-band observations of the GRB 091117 error box  
(Cummings et al., GCNC 10171) with the 1.5m OSN telescope. The  
observations were performed on Nov 18.895-18.958 UT (27.7-29.3 hours  
post GRB). Visual comparison with the DSS does not reveal any new  
source in the error box brighter than I~20.5."


GRB_name: GRB091117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10173
SUBJECT: GRB 091117:  XRT source coincident with a DSS galaxy
DATE:    09/11/19 04:56:34 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) reports:

"Inspection of Swift/XRT observations of the short GRB 091117 (GCN 
#10171) reveals an X-ray source coincident with an extended object in 
DSS images.  The DSS object (APMUKS B020129.84-171252.3) is located at 
the following coordinates (J2000):
 RA = 02:03:53.35
 DEC = -16:58:30.6
Optical observations are in progress."


GRB_name: GRB091117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10174
SUBJECT: GRB 091117:  Magellan optical observations
DATE:    09/11/19 06:06:15 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) and J. Mulchaey (OCIW) report:

"We obtained optical r-band observations of the BAT error circle of GRB 
091117 (GCN #10171) with IMACS on the Magellan/Baade 6.5-m telescope 
starting on 2009 Nov 19.06 UT.  A comparison to DSS images reveals no 
new sources brighter than the DSS limit of about 21 mag.

The galaxy coincident with the XRT source within the BAT error circle 
(GCN #10173) has a face-on spiral morphology.  We find a single apparent 
point source coincident with one of the spiral arms.  This object may be 
the optical afterglow of GRB091117 or an unrelated bright HII region. 
Additional observations are planned to determine if the source exhibits 
fading behavior.

An image of the galaxy is available from:
 http://www.cfa.harvard.edu/~eberger/GRB091117_Magellan.gif


GRB_name: GRB091117A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10175
SUBJECT: Konus-Wind observations of GRB 091117A
DATE:    09/11/19 11:00:48 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The short hard GRB 091117A (localized by Swift-BAT and IPN,
Cummings et al., GCN 10171) triggered Konus-Wind
at T0=63869.513 s UT (17:44:29.513).

The burst light curve consists of a single peak with a total
duration of ~0.3 s. The Konus-Wind light curve of this GRB
is available at http://www.ioffe.ru/LEA/GRBs/GRB091117_T63869/

As observed by Konus-Wind the burst
had a fluence of 1.9(-0.5, +0.7)x10-6 erg/cm2,
and a 16-ms peak flux measured from T0
of 1.4(-0.4. +0.7)x10-5 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+0.256 s) can be fitted
(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 = -0.42(-0.41, +0.64),
and Ep = 663(-225, +396) keV (chi2 = 29/23 dof).

Fitting by GRB (Band) model yields the same alpha
and Ep values with the high energy photon index
beta = -9.4 (< -1.9).

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


GRB_name: GRB091117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10176
SUBJECT: GRB 091117: Gemini-North spectroscopy of DSS galaxy
DATE:    09/11/19 11:01:41 GMT
FROM:    Ryan Chornock at UC Berkeley  <chornock@astro.berkeley.edu>

R. Chornock and E. Berger (Harvard) report:

We obtained spectra of the DSS galaxy coincident with the XRT source (GCN 10173)
seen in the Swift observations of the short GRB 091117 (GCN 10171) using GMOS on
Gemini-North.  A pair of 1800s exposures using the R400 grating were taken
starting at 07:27 UT on Nov. 19.  Numerous emission lines are present at
z=0.096.  The slit was aligned through both the nucleus and the point source on
the spiral arm (GCN 10174).  The off-nuclear point source exhibits the
high-equivalent-width nebular emission lines expected of an H II region and is
therefore unlikely to be related to the afterglow of GRB 091117.  In addition,
the nuclear spectrum shows a broad component to the H-alpha line (FWHM ~ 1670
km/sec), indicative of an AGN.  The AGN could also be responsible for the
observed X-ray emission.


GRB_name: GRB091117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10177
SUBJECT: GRB 091117: Swift XRT refined analysis
DATE:    09/11/19 15:58:16 GMT
FROM:    Valerio D'Elia at INAF-OAR  <delia@mporzio.astro.it>

V. D'Elia, G. Stratta, M. Perri (ASDC), P.A. Evans and M.R. Goad (U.  
Leicester),
J. Cummings (GSFC/CRESST), S. Campana (INAF-OAB) report on behalf of  
the Swift-XRT team:

We have analysed 3.85 ks of XRT data for GRB 091117 (Cummings et al.  
et al.
GCN Circ. 10171), from 96765 s to 119.4 ks after the Suzaku trigger. The
data are entirely in Photon Counting (PC) mode. Two sources are detected
at the edge of the BAT error circle.

Source #1:
using 722 s of XRT Photon Counting mode data and 1 UVOT
images, we find an astrometrically corrected X-ray position (using the
XRT-UVOT alignment and matching UVOT field sources to the USNO-B1
catalogue): RA, Dec = 30.97240, -16.97490 deg which is equivalent to:

RA (J2000):  02 03 53.38
Dec (J2000): -16 58 29.8

with an uncertainty of 3.6 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).

The source is at a count rate level of (4.8+/-1.4)e-3 counts/s.
The light curve does not allow us to assess if the source is fading.

This source has been reported by Berger et al. (GCN Circ. 10173)
to be coincident with the DSS galaxy APMUKS B020129.84-171252.3
at redshift z=0.096 (Chornock & Berger 2009, GCN Circ. 10176)
We can't distinguish if this is nuclear emission from the AGN
discussed by Berger et al. (GCN Circ. 10176)

Source #2:
the other source has a count rate level of
(2.7+/-1.1)e-3 counts/s and is at RA, Dec= 30.988333, -16.948583 deg
which is equivalent to

RA (J2000): 02 03 57.2
Dec(J2000): -16 56 54.9

with an uncertainty of 7.7 arcsec (radius, 90% confidence).

The light curve does not allow us to assess if the source is fading.

We note that there is a known source (2MASX J02035665-1656585 at  
z=0.096220)
located 8.8 arcsec from Source #2.

Further observations are planned for this field.

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


GRB_name: GRB091117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10178
SUBJECT: GRB091117: Gemini South Observations
DATE:    09/11/19 16:17:09 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

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

We have imaged the field of GRB091117 (Cummings et al., GCN 10171) with
the Gemini Multi-Object Spectrograph on the 8 m Gemini South telescope
beginning at 7:07 UT on 19 November (~ 37 hours after the burst trigger
time).  Observations were conducted in the Sloan g', r', and i' filters
under poor seeing conditions (~ 2" FWHM).

We find no new point sources at the location of either candidate X-ray
afterglow (Berger, GCN 10173; D'Elia et al., GCN 10177).  The limiting
magnitude of our images is g' >~ 24 mag for isolated point sources;
however we note that both XRT positions fall close to nearby galaxies and
are contaminated by galaxy light.

The galaxy system near source 2 appears to be highly disturbed, possibly
indicative of recent merger activity.


GRB_name: GRB091117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10179
SUBJECT: GRB 091117:  Evidence for Variability of XRT Source #1
DATE:    09/11/19 16:49:49 GMT
FROM:    Derek Fox at PSU  <dfox@astro.psu.edu>

D. B. Fox (Penn State) reports:

"Analysis of the first 3.85 ks of Swift XRT exposure (D'Elia et al.,
GCN 10177) on the field of GRB 091117 (Cummings et al., GCN 10171), as
reduced via standard XRT pipeline processing, yields a total of 13
photons from Source #1 (Berger, GCN 10173) and 7 photons from Source
#2 (D'Elia et al., GCN 10177).

The resulting distribution of photon arrival times for Source #1 is
inconsistent with a constant count rate at roughly 93% confidence,
according to a single-sample KS test, suggesting fading or variable
behavior of this X-ray source.  The maximum deviation from a constant
count rate model occurs after 35% of the integrated exposure, when 9
of 13 photons (70% of total counts) have been collected.

The same test applied to the arrival times for Source #2 indicates
consistency with a constant count rate (p-value of 0.90), however, the
sensitivity of the test is more strongly limited by photon statistics
in this case, such that we would not expect fading/variability at the
level suggested in Source #1 to be apparent in Source #2, even if
present."


GRB_name: GRB091117A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10180
SUBJECT: GRB 091117 BAT refined analysis
DATE:    09/11/19 19:18:16 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), A. M. Parsons (GSFC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-0.16 to T+10 sec, we report further analysis
of BAT/IPN GRB 091117 (trigger #376211) (Cummings, et al.,
GCN Circ.# 10171).  The BAT ground-calculated position is as reported
before, RA, Dec = 30.945, -16.944, which is
RA (J2000) 02h 03m 46.9s
Dec (J2000) -16d 56' 38.0"
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 12%.
 
The mask-weighted light curve shows two peaks. The first is a weak spike
at T+0 lasting for 0.15 sec. The second is the main spike at T+2.7
lasting for 0.4 sec.  T90 (15-350 keV) is 0.43 +- 0.05 sec (estimated
error including systematics).  There is an indication of possible
extended-time soft emission in the mask-weighted image covering ~1 minute
in the 15-50 keV band following the burst (2.6 sigma).  There is no
indication of a persistent source in the BAT energy band at this position
at other times.
 
The time-averaged spectrum from T-2.5 to T+3.2 sec is best fit by a
simple power-law model.  The power law index of the time-averaged
spectrum is 0.8 +- 0.3.  The fluence in the 15-150 keV band is
3.5 +- 1.2 x 10-7 erg/cm2**.  The 1-sec peak photon flux measured from
T+2.3 sec in the 15-150 keV band is 2.5 +- 0.5 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.

Because of the ground-detected nature of this burst, the usual automated
data products are not currently available.


GRB_name: GRB091117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10181
SUBJECT: GRB 091117: Swift-XRT observations
DATE:    09/11/19 23:47:45 GMT
FROM:    Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>

V. D'Elia, M. Perri (ASDC), J. Cummings (GSFC/CRESST)  report
on behalf of the Swift-XRT team:

We have analysed further 4.0 ks of XRT data for GRB 091117 (Cummings
et al. GCN Circ. 10171), from 161.3 ks to 172.4 ks after the trigger.
The data are entirely in Photon Counting (PC) mode.

We found that Source #1 (Berger, GCN Circ. 10173; D'Elia et al.,
GCN Circ. 10177; Fox, GCN Circ. 10179) is detected with a count rate of
(1.9+/-0.9)e-3 cts/s, thus showing some evidence of fading with respect
to the first Swift follow-up observation (errors are given at the
1-sigma level). We note that the photon statistics is low and further
observations are needed to firmly assess that this source is the X-ray
afterglow of the burst.

Source #2 (D'Elia et al., GCN Circ. 10177; Fox, GCN Circ. 10179) is
instead
not detected. The derived 3-sigma upper limit value on its count rate,
~3.3e-3 cts/s, does not allow to constrain the temporal behavior of this
source.

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


GRB_name: GRB091117A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10182
SUBJECT: GRB 091117: VLA radio observations
DATE:    09/11/20 04:08:09 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger and W. Fong (Harvard) report:

"We imaged the BAT error circle of the short GRB 091117 (GCN #10171) 
with the VLA at a frequency of 8.46 GHz starting on 2009 Nov 20.07 UT. 
In the 1 hour observation only a single source is detected within the 
BAT error circle, in coincidence with the galaxy near XRT Source #2 
(GCNs #10177,10178).  However, inspection of the NRAO VLA Sky Survey 
(NVSS) reveals a coincident archival source, indicating that this is not 
the afterglow of GRB 091117.  No other sources are detected within the 
BAT error circle to a 3-sigma limit of about 120 microJy."


GRB_name: GRB091117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10183
SUBJECT: GRB 091117:  2nd epoch of Magellan optical observations
DATE:    09/11/20 06:00:05 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard) and I. Momcheva (OCIW) report:

"We obtained a second set of optical r-band observations of the BAT 
error circle of GRB 091117 (GCN #10171) with IMACS on the Magellan/Baade 
6.5-m telescope starting on 2009 Nov 20.03 UT.  A comparison to our 
first epoch of Magellan observations (GCN #10174) reveals no variable 
sources within the BAT error circle or in coincidence with the two XRT 
sources (GCNs #10173,10177,10181) to a limit of r~24 mag.  The point 
source identified as an HII region (GCN #10176) has not varied in 
brightness.  Further analysis is in progress."


GRB_name: GRB091117A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10184
SUBJECT: GRB 091117A: Swift/UVOT followup observations
DATE:    09/11/20 11:32:17 GMT
FROM:    Alice Breeveld at MSSL-UCL  <aab@mssl.ucl.ac.uk>

A. Breeveld (MSSL/UCL), M. De Pasquale (MSSL/UCL) and J. R. Cummings 
(GSFC/UMBC) report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 091117A 
96767s (~27 hours) after the BAT trigger (Cummings et al., GCN Circ. 
10171). The galaxy described by Berger and Mulchaey (GCN Circ. 10174) 
as being a possible host, is clearly seen as an extended object in the 
UVOT data. There is no evidence of a fading source at either of the 
two XRT source positions (D'Elia et al., GCN Circ. 10177) when 
compared with data taken ~47 hours after the burst. In the case of 
source 1, which is coincident with the spiral galaxy, we checked for 
fading using an aperture of 2" at the refined XRT position as well as 
using an aperture of 8" to contain the whole galaxy.

Magnitudes measured with a non-standard 8" aperture to include the 
whole galaxy, using the UVOT photometric system (Poole et al. 2008, 
MNRAS, 383, 627), for the initial summed exposures are:

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

white            97197       113850          875         17.56  0.01
v               109296       109642          340         17.05  0.06
u                96767       119064         2614         17.60  0.02

Upper limits (3 sigma) obtained at the position of source 2 (D'Elia et 
al., GCN Circ. 10181) are as follows:

white            97197       113850          875         21.89 (UL)
v               109296       109642          340         19.72 (UL)
u                96767       119064         2614         21.52 (UL)


None of the values quoted above are 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: GRB091117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10185
SUBJECT: GRB 091117: TNG optical observations
DATE:    09/11/21 01:24:23 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo (INAF-OAB), L.A. Antonelli (INAF-OAR), A. de Ugarte Postigo
(INAF-OAB), A.J. Castro-Tirado (IAA-CSIC), J. Gorosabel (IAA-CSIC), E.
Palazzi (IANF-IASFBo), S. Covino (INAF/OAB), J.M. de Leon Cruz,
(IAA-CSIC), C. Padilla (TNG) report:

We observed the field of GRB 091117 (Cummings et al. GCN 10171) with the
Italian 3.6m TNG telescope, sited in Canary Islands (Spain) with the
DOLORES camera in imaging mode on Nov 19.995 UT. Observations were carried
out in V, R and I band.

We compared our 900 s I-band image with the one obtained in the same band
with the 1.5m OSN telescope on Nov 18.9 UT (Casanova et al., GCN 10172).
Image subtraction performed with the ISIS package does not show any
variable source in the overlap region covered by the two images (about 90%
of the BAT error circle; Sakamoto et al, GCN 10180). In particular we note
that no variability is detected for XRT source #1 (Berger, GCN. 10173;
D'Elia et al., GCN 10177; Fox, GCN 10179) while no conclusion can be drawn
for XRT source #2 (D'Elia et al., GCN 10177; Fox, GCN 10179) because it is
saturated in the TNG image.

An image showing the result of image subtraction is available here:
http://www.brera.inaf.it/utenti/davanzo/grb/GRB091117_subtraction.jpg

The 3sigma limiting magnitudes are I~22.9 and I~23.6 for the OSN and TNG
images respectively.


GRB_name: GRB091117A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10186
SUBJECT: GRB 091117A: Suzaku WAM observation of the prompt emission
DATE:    09/11/22 07:30:19 GMT
FROM:    Hidenori Hayasi at Miyazaki U  <hayasi@astro.miyazaki-u.ac.jp>

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

The short GRB 091117A (Swift/BAT Detected in ground analysis ; Cummings et al.,
GCN 10171) triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers an 
energy range of 50 keV - 5 MeV at 2009-11-17 17:44:25.253 UT (=T0). 

The observed light curve shows a single peak starting at T0 s, ending 
at T0+1 s with a duration (T90) of about 0.4 seconds.
The fluence in 100 - 1000 keV was 1.54 (-0.26/+0.25) x10^-6 erg/cm^2. 
The 1-s peak flux measured from T0 s was 2.78 (-0.30,+0.37) photons/cm^2/s 
in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0 s to 
T0+1 s is well fitted by a single power-law with a photon index 
of 1.29 (-0.13,+0.13) (chi^2/d.o.f. = 42/33).

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

The light curves for this burst are available at:

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


GRB_name: GRB091120A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10187
SUBJECT: GRB 091120: Fermi GBM observation
DATE:    09/11/24 10:14:38 GMT
FROM:    David Gruber at MPE  <dgruber@mpe.mpg.de>

David Gruber (MPE) reports on behalf of the Fermi GBM Team: 


"At 04:34:40.23  UT on 20 November 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091120 (trigger 280384482 / 091120191).

The on-ground calculated location, using the GBM trigger 
data, is RA = 224.8, DEC = -24.8 (J2000 degrees, 
equivalent to 14h 59m, -24d 48'), with an uncertainty 
of 1.32 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 45 degrees.
Moreover, this burst was bright enough to result in
a Fermi spacecraft repointing maneuver.

The GBM light curve consists of several peaks with a 
duration (T90) of about 52 s (8-1000 keV). 
The time-averaged spectrum from T0-3 s to T0+56 s is 
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.17 +/- 0.02 and
the cutoff energy, parameterized as Epeak, is 129 +/- 3 keV.
(C-stat 691 for 362 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(3.02 +/- 0.04)E-5 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+26.6 s in the 8-1000 keV band 
is 21.3 +/- 0.4 ph/s/cm^2.

A Band function fits the spectrum equally well (C-stat 687 for 361 d.o.f.) 
with Epeak= 124 +/- 4 keV, alpha = -1.15 +/- 0.02 
and beta = -2.98 +/- 0.27. 

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


GRB_name: GRB091120A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10188
SUBJECT: GRB 091120: MAXI GSC detection
DATE:    09/11/24 11:19:53 GMT
FROM:    Atsumasa Yoshida at Aoyama Gakuin U  <grbalert-ylab@phys.aoyama.ac.jp>

M.Nakajima (Nihon U.), S.Nakahira (AGU), M.Sugizaki, M.Kohama(RIKEN),
M.Suzuki (ISAS/JAXA), A.Yoshida, K.Yamaoka (AGU), 
N.Kawai, M.Morii(Tokyo Tech), H.Negoro (Nihon U.), M.Matsuoka, H.Tomida,
S.Ueno(ISAS/JAXA), Y.Ueda, S.Eguchi (Kyoto U.) and H.Tsunemi (Osaka Univ.)  
on behalf of the MAXI team report:

The Gas Slit Camera (GSC) of MAXI detected a bright hard X-ray
transient at 04:34:56 on 20 November 2009 (UT).  This event should
correspond to a GRB detected by Fermi-GBM, INTEGRAL SPI-ACS
andKonus-Wind.

The location of the source derived from the GSC data is 
(R.A.,Dec.)=(226.81 deg, -21.79 deg)=(15:07:14.40, -21:47:24.0)(J2000) 
with an uncertainty of about 0.5 degree.  This is consistent with that
reported by Gruber (GCNC10187) within an error.

The GSC FOV scanned over the source from 04:34:56 (UT) (16 seconds
after the GBM trigger) for about 40 seconds.  The average X-ray flux
over the observation is 4.9x10^-8 erg/cm2/s in 3-15 keV.  Significant
intensity variation was clearly seen in the light curve. 

MAXI is currently under the commissioning phase and the systematic
uncertainty in localization will be significantly improved with the
progress of the alignment calibration.
This message may be citable.


GRB_name: GRB091120A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10189
SUBJECT: Konus-Wind observation of GRB 091120
DATE:    09/11/24 13:28:56 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 091120 reported by Fermi GBM, (Gruber, GCN 10187)
and localized by MAXI GSC (Nakajima et al., GCN 10188)
triggered Konus-Wind at T0=16476.183 s UT (04:34:36.183).

The burst light curve consists of several peaks with a total
duration of ~55 s. The Konus-Wind light curve of this GRB
is available at http://www.ioffe.ru/LEA/GRBs/GRB091120_T16476/
Considerable hard to soft spectral evolution is noticed during the
initial part of the burst.

As observed by Konus-Wind the burst
had a fluence of 2.6(+/-0.3)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0 + 25.344s
of 2.4(+/-0.3)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+57.600 s) is well fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), with
alpha = -1.2(-0.25, +0.28),
and Ep = 145(-18, +26) keV (chi2 = 67/61 dof).

The spectrum of the most intense peak (measured
from T0+24.832 to T0+33.024 s) is also well fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -1.0(-0.4, +0.45),
and Ep = 101(-15, +16) keV (chi2 = 48/61 dof).


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


GRB_name: GRB091120A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10190
SUBJECT: IPN Triangulation of GRB091120
DATE:    09/11/24 19:37:54 GMT
FROM:    Kevin Hurley at UCBerkeley/SSL  <khurley@ssl.berkeley.edu>

K. Hurley and T. Cline, on behalf of the Mars Odyssey
and Konus GRB teams,

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

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

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, and D. Frederiks, 
on behalf of the Konus-Wind team,

V. Connaughton, M. Briggs, and C. Meegan, on
behalf of the Fermi-GBM team,

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

D. M. Smith, R. P. Lin, J. McTiernan, R. Schwartz, C. Wigger, and W.
Hajdas, on behalf of the RHESSI GRB team, and 

G. Di Cocco, F. Fuschino, M. Galli, C. Labanti, and M. Marisaldi, 
on behalf of the AGILE MCAL team, report:

AGILE (MiniCalorimeter), INTEGRAL (SPI-ACS), Konus-Wind, and
Mars Odyssey (HEND) observed GRB091120 (Gruber et al. GCN 10187;
Nakajima et al. GCN 10188; Golenetskii et al. GCN 10189).  We
have triangulated this burst to an error ellipse which may be
approximated by the following preliminary, 3 sigma error box:

-----------------------------------------------
    RA(2000), deg              Dec(2000), deg
-----------------------------------------------
Center:
  227.393 (15h 09m 34s)   -19.849 (-19d 50' 56")
Corners:
  226.629 (15h 06m 31s)   -22.609 (-22d 36' 33")
  226.458 (15h 05m 50s)   -22.135 (-22d 08' 05")
  228.539 (15h 14m 09s)   -15.899 (-15d 53' 57")
  228.535 (15h 14m 08s)   -16.885 (-16d 53' 08")
-----------------------------------------------

The IPN-only error box area is approximately 6600 square
arcminutes, and is consistent with the MAXI error circle; 
the IPN/MAXI error box area is approximately 1000 square 
arcminutes.  This triangulation can be improved.

A figure showing the GBM, MAXI, and IPN localizations is
posted at ssl.berkeley.edu/ipn3/091120


GRB_name: GRB091127A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10191
SUBJECT: GRB 091127: Swift detection of a burst
DATE:    09/11/27 23:36:19 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

E. Troja (NASA/GSFC/ORAU), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), J. Mao (INAF-OAB), F. E. Marshall (NASA/GSFC),
J. P. Osborne (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC),
A. Rowlinson (U Leicester) and M. Stamatikos (OSU/NASA/GSFC) report on
behalf of the Swift Team:

At 23:25:45 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091127 (trigger=377179).  Swift did not immediately slew
to the burst due to Earth limb constraint. 
The BAT on-board calculated location is 
RA, Dec 36.571, -18.954 which is 
   RA(J2000) = 02h 26m 17s
   Dec(J2000) = -18d 57' 12"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 10 sec.  The peak count rate
was ~30,000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to an observing constraint, Swift will not slew until 
T0+50 minutes. There will be no XRT or UVOT data until
this time. 

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


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10192
SUBJECT: GRB 091127: Liverpool Telescope afterglow candidate
DATE:    09/11/28 00:38:22 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

R.J. Smith, S. Kobayashi (Liverpool JMU), C. Guidorzi (U. Ferrara),
C.G. Mundell (Liverpool JMU) on behalf of a larger collaboration report:

"The 2-m Liverpool Telescope robotically followed up GRB 091127 (Swift
trigger 377179; Troja et al. GCN 10191) 2.35 min after the GRB trigger
time. The automatic "detection mode" procedure detected an uncatalogued
fading afterglow candidate at:

02:26:19.89 , -18:57:08.60    (J2000) uncertainty 0.5"

with magnitude of about R = 15.0 (vs USNOB1)

Observations and analysis are ongoing.


GRB_name: GRB091127A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10193
SUBJECT: GRB 091127: Swift/UVOT Detection of an Optical Afterglow
DATE:    09/11/28 00:55:41 GMT
FROM:    Stefan Immler at NASA/GSFC  <stefan.m.immler@nasa.gov>

GRB 091127: Swift/UVOT Detection of an Optical Afterglow

S. Immler (CRESST/UMCP/GSFC) and E. Troja (NASA/GSFC/ORAU) report
on behalf of the Swift UVOT Team:

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 3219 seconds after the BAT trigger. There is an afterglow in
the rapidly available 2.7'x2.7' sub-image at
   RA(J2000)  =    02:26:19.89 = 36.58288
   DEC(J2000) = -18:57:08.5  = -18.95235
with a 90%-confidence error radius of about 0.61 arc sec. This position
is 40.9 arc sec. from the center of the BAT error circle. The estimated
magnitude is 16.21 with a 1-sigma error of about 0.14. No correction has
been made for the expected extinction corresponding to E(B-V) of 0.04.

The optical afterglow position is consistent with the Liverpool Telescope
afterglow candidate (Smith et. al GCN 10192) that was detected with a
magnitude of around R=15.0.


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10194
SUBJECT: GRB 091127: REM NIR afterglow detection
DATE:    09/11/28 02:08:52 GMT
FROM:    Angelo Antonelli at Obs. Astro. di Roma  <a.antonelli@oa-roma.inaf.it>

D. Fugazza, L.A. Antonelli, S. Covino, P. D'Avanzo, S. Campana, G. Chincarini,
V. D'Elia,  F. D'Alessio, F. Fiore, P. Goldoni, C.  Guidorzi, E. Maiorano, L.
Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Tagliaferri, G.
Tosti, V. Testa, S.D. Vergani, F. Vitali report on behalf of the REM team:

"The robotic 60-cm REM telescope located at La Silla (Chile) observed
automatically the field of the GRB 091127 (Troja et al. GCN 10191) on Nov 27
starting observations about 90 min after the GRB. We clearly detect a NIR source
at RA(J2000)=02:26:19.8, Dec.(J2000)=-18:57:08.3 with an uncertainty of 1" which
is compatible with the position of the optical afterglow observed for this burst
(Smith et al., GCN 10192; Immler & Troja, GCN 10193). The source was detected in
all NIR filters and showed at the observation time a magnitude H= 12.6+/-0.15
and J=13.1+/-0.23, calibrated against 2MASS. Further analysis is in progress. 

This message may be citeted."




-------------------------------------------------
This mail sent through IMP: http://horde.org/imp/


GRB_name: GRB091127A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10195
SUBJECT: GRB 091127 : GROND observations
DATE:    09/11/28 02:17:35 GMT
FROM:    Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>

Adria Updike (Clemson University), Andrea Rossi (Tautenburg Obs.), Arne
Rau, Jochen Greiner, Paulo Afonso and Abdullah Yoldas (all MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 091127 (Swift trigger 377179; Trojo et al.,
GCN #10191) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla
Observatory (Chile).

Observations started at 00:24 UT on Nov 28, 58 min after the GRB trigger,
and are continuing.

For the afterglow candidate reported by Smith et al. (GCN #10192) we
estimate the following preliminary magnitudes (in the AB system):

g = 16.63 +- 0.15
r = 16.53 +- 0.15
i = 16.42 +- 0.15
z = 16.35 +- 0.15
J = 16.40 +- 0.10
H = 16.36 +- 0.14
K analysis on going

Given the smal g-r color, these values are in agreement
with a afterglow at redshift z<3.5.

A second epoch, at 01:33 UT, 2h and 8 min after the burst
shows the afterglow is faded to r= 16.96+-0.15 (AB system).

Given magnitudes are calibrated against GROND zeropoints as well as 2MASS
field stars. The errors take in account zero point uncertainties.  
Magnitudes are not corrected for the expected Galactic foreground
extinction corresponding to a reddening of E_(B-V)=0.038 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10196
SUBJECT: GRB 091127: NOT observations
DATE:    09/11/28 03:09:15 GMT
FROM:    Dong Xu at DARK,NBI  <dong@astro.ku.dk>

D. Xu (WIS,DARK/NBI), D. Malesani, J. Hjorth (DARK/NBI), A.A. Djupvik, 
J. Datson (NOT), P. Jakobsson (Univ. of Iceland), A. Carmona, C. 
Baldovin-Saavedra (ISDC & Geneva Observatory) report on behalf of a 
larger collaboration:

We observed the field of GRB091127 (Troja et al., GCN 10191) with the 
Nordic Optical Telescope equipped with StanCam and NOTCam, starting at 
00:36:03 UT on Nov. 28th, 70.3 mins after the burst.

Preliminary data analysis confirms the bright optical afterglow (Smith 
et al., GCN 10192; Immler et al., GCN 10193) and shows

R~16.3  at 00:38 UT
I~16.2   at  01:09 UT
R~16.5  at 01:15 UT
J~15.9   at  01:43 UT
H~15.4  at 01:34 UT
K~14.8  at 01:26 UT.

The R-band afterglow light curve is decaying slowly during our 
observations.


GRB_name: GRB091127A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10197
SUBJECT: GRB 091127: Swift-BAT refined analysis
DATE:    09/11/28 03:23:46 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), E. Troja (NASA/GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 091127 (trigger #377179)
(Troja, et al., GCN Circ. 10191).  The BAT ground-calculated position is
RA, Dec = 36.581, -18.948 deg, which is 
   RA(J2000)  =  02h 26m 19.5s 
   Dec(J2000) = -18d 56' 51.1" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 4%.
 
The mask-weighted light curve shows three main peaks.  The first starts
at ~T-0.3 sec and peaks at ~T0.  The second peaks at ~T+1.1 sec.
The third peaks at ~T+7 sec and ends at ~T+10 sec.  T90 (15-350 keV)
is 7.1 +- 0.2 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.4 to T+7.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.05 +- 0.07.  The fluence in the 15-150 keV band is 9.0 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.25 sec in the 15-150 keV band
is 46.5 +- 2.7 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/377179/BA/


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10198
SUBJECT: GRB 091127: CAHA 1.23m I-band observations 
DATE:    09/11/28 03:25:55 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

J. Gorosabel (IAA-CSIC), A. de Ugarte Postigo (INAF/OAB), V. Terron  
(IAA-CSIC), M. Fernandez (IAA-CSIC), P. Kubanek (IAA-CSIC), M. Jelinek  
(IAA-CSIC), report on behalf of a larger collaboration:

"We have detected the GRB 091127 optical afterglow (Smith et al.  GCNC  
10192; Immler  et al. GCN 10193) by means of a single I-band frame  
(Texp=120s) taken with the CAHA 1.23m Telescope. The observations,  
carried out on Nov. 28.03862-28.04000 UT (~1.5 hours post burst) under  
poor weather conditions, yielded a preliminary I-band magnitude of  
I~16.4, assuming I=13.62 for the USNO-B1.0 star located at (RA,DEC) =  
(02:26:21.063,-18:57:19.02; J2000)."


GRB_name: GRB091127A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10199
SUBJECT: GRB 091127: Swift/UVOT observations
DATE:    09/11/28 05:17:52 GMT
FROM:    Stefan Immler at NASA/GSFC  <stefan.m.immler@nasa.gov>

S. Immler (CRESST/UMCP/GSFC) and Troja (NASA/GSFC/ORAU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 091127
3219 s after the BAT trigger (Troja et al., GCN Circ. 10191).

We detect the optical afterglow at the refined UVOT position
RA, Dec 36.58288, -18.95239, which is

     RA  (J2000)  02:26:19.89
     Dec (J2000) -18:57:08.63

with an estimated uncertainty of 0.55 arcsec (radius, 90% confidence).
This position is consistent with ground-based optical/IR detections of
the afterglows (Smith et al., GCN 10192; Fugazza et al., GCN 10194;
Updike et al., GCN 10195; Xu et al., GCN 10196; Gorosabel et al.,
GCN 10198). Preliminary magnitudes are reported below.

Filter    T_start(s) T_stop(s)  Exposure(s)   Mag  Err
------------------------------------------------------------------------
white      3219       3369      147.4          16.2 +/- 0.1
v          3375       3575      196.6          17.0 +/- 0.1
uvw1       3785       5600     156.1          15.9 +/- 0.1
uvm2       3580       3780      196.6         15.6 +/- 0.1
-------------------------------------------------------------------------

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.04 in the direction of the burst
(Schlegel et al. 1998, ApJS, 500, 525). The photometry is on the UVOT
photometric system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10200
SUBJECT: GRB 091127: TAROT La Silla observatory optical decay
DATE:    09/11/28 08:22:39 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

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

We imaged the field of GRB 091127 detected by Swift
(trigger 377179) with the TAROT robotic telescope (D=25cm)
located at the European Southern Observatory,
La Silla observatory, Chile.

The observations started 1 hour after the GRB trigger
(event occured during dusk). The elevation of the field
increased from 58 degrees above horizon and weather conditions
were good.

We detected the optical couterpart (OT) mentioned by
Smith et al. 2009 (GCNC 10192). As the OT is bright,
we used only R filtered images. We used the reference
star at coordinates 02:26:15.06 -18:54:57.3 R=15.82,
(V-R)=0.24 which is the closest star with (V-R) close
to that of the GRB (V-R~0.1 according to GROND observations
by Updike et al. GCNC 10195). The star at coodinates
02:26:21.07 -18:57:18.9 R=14.02 lies at 20 arcsec of the OT.
We substract this star before photometry:

-----------------------------------
  Tstart    Tstop  Rmag
  (min)     (min)
-----------------------------------
   69.12 - 82.19  16.4 +/- 0.2
  106.59 - 119.67 16.7 +/- 0.3
  144.33 - 157.41 16.7 +/- 0.3
  182.09 - 222.83 17.0 +/- 0.2
  229.91 - 346.22 17.1 +/- 0.2
  367.71 - 444.61 17.4 +/- 0.2
-----------------------------------

The decay is very low since the OT decreased
of only 1 mag in 5 hours !


GRB_name: GRB091127A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10201
SUBJECT: GRB 091127: Swift-XRT afterglow detection and analysis
DATE:    09/11/28 08:50:28 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, K.L. Page (U. Leicester) and E. Troja (NASA/GSFC/ORAU) report on
behalf of the Swift-XRT team:

We have analysed 2.4 ks of XRT data for GRB 091127 (Troja et al. GCN
Circ. 10191), from 3.2 ks to 15.8 ks after the BAT trigger. The data
comprise 761 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. Using 1066 s of PC mode data and 4 UVOT images, we
find an enhanced XRT position (using the XRT-UVOT alignment and matching
UVOT field sources to the USNO-B1 catalogue): RA, Dec = 36.58290,
-18.95250 which is equivalent to:

RA (J2000): 02 26 19.89
Dec(J2000): -18 57 08.9

with an uncertainty of 1.4 arcsec (radius, 90% confidence). This is
consistent with the optical/UV/IR position reported in GCN Circs
10192-4.

The light curve can be modelled with a power-law decay with a decay
index of alpha=1.09 (+/-0.05).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.97 (+/-0.08). The
best-fitting absorption column is 7.9 (+1.7, -1.6) x 10^20 cm^-2, in
excess of the Galactic value of 2.8 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 1.98 (+0.15, -0.14)
and a best-fitting absorption column of 9.8 (+3.3, -3.1) x 10^20 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 3.9 x 10^-11 (4.9 x 10^-11) erg cm^-2
count^-1.

If the light curve continues to decay with a power-law decay index of
1.09, the count rate at T+24 hours will be 0.24 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.3 x
10^-12 (1.2 x 10^-11) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00377179.

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


GRB_name: GRB091127A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10202
SUBJECT: GRB 091127: Gemini-N redshift
DATE:    09/11/28 11:27:46 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara, D. Fox (PSU), A. Levan (Warwick U.) and
N. Tanvir (U. Leicester) report:

On November 28.40 UT we observed the afterglow of the Swift
GRB 091127 (Troja et al. GCN 10191; Smith et al. GCN 10192)
with the GMOS-N spectrograph on Gemini North. 

The observation consists of 2 exposures of 900 seconds each
with the R400 grating, covering 4000-8000A wavelength range.

The spectra shows a bright featureless continuum and two emission
lines which we identified as [OIII]4959 and 5007 respectively
at the common redshift of z = 0.490.

Therefore we suggest this as redshift for GRB 091127.

We thank the Gemini-N support staff, in particular A. Stephens,
for performing these observations.


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10203
SUBJECT: GRB 091127: MASTER early optical transient polarimetry
DATE:    09/11/28 16:31:40 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

A.Belinski, E. Gorbovskoy, V. Lipunov,
V.Kornilov, D.Kuvshinov,  N.Shatskiy, N.Tyurina, P.Balanutsa, V.V.Chazov,
D. Zemnukhov, A.Kuznetsov

Sternberg Astronomical Institute, Moscow State University

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

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

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

V.Yurkov
Blagoveschensk Educational State University, Blagoveschensk 

MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru,
D= 2x400 mm, FOV= 2x4  square degrees, 2x16 Mpx Apogee CCD) located
at Kislovodsk (2000m)  was responted to the  GRB 091027
(Troja et al., GCN 10191)   9 sec after Notice time and
91 s after the GRB time at very large zenit distance
(~4 degrees up to horizont).

We saw bright optical counterpart (~14 mag, 91-111 sec after GRB Time) at
Liverpool position (Smith et al., GCN 10192) in both polarizations.

We took ~20  images with synchronous exposition in two polarizations
before GRB setting with  growing exposition from 20 to 160 sec.
We saw possible brightening around 2 min (after GRB Time).

The reduction is continued.

The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB091127A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10204
SUBJECT: GRB 091127: Fermi GBM detection
DATE:    09/11/28 22:01:05 GMT
FROM:    Colleen A. Wilson at NASA/MSFC/NSSTC  <colleen.wilson@nasa.gov>

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

"At 23:25:45.48 UT on 27 November 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091127 (trigger 281057147 / 091127976), which was
also detected by the SWIFT-BAT (Troja et al. 2009, GCN 10191)
The GBM on-ground location is consistent with the Swift position.
 
The angle from the Fermi LAT boresight is 25 degrees.

The GBM light curve consists of three peaks
with a duration (T90) of about 9 s (8-1000 keV).
The time-averaged spectrum from T0+0.002 s to T0+9.984 s is
adequately fit by a Band function with Epeak = 36 +/- 2 keV,
alpha = -1.27 +/- 0.06, and beta = -2.20 +/- 0.02
(chi squared 645.8 for 445 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.87 +/- 0.02)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1 s in the 8-1000 keV band
is 46.9 +/- 0.9 ph/s/cm^2.

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


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10205
SUBJECT: GRB 091127: Further NOT optical observations
DATE:    09/11/28 23:09:07 GMT
FROM:    Dong Xu at DARK,NBI  <dong@astro.ku.dk>

D. Xu (WIS, DARK/NBI), D. Malesani, J. Hjorth (DARK/NBI), P. Jakobsson 
(Univ. of Iceland), A. Carmona, C. Baldovin-Saavedra (ISDC & Geneva 
Observatory) report on behalf of a
larger collaboration:

We continued to observe the field of GRB091127 (Troja et al., GCN 10191; 
Smith et al., GCN 10192; Immler et al., GCN 10193) at the Nordic Optical 
Telescope equipped with StanCam. Among a series of observations, a 60 s 
R-band frame was obtained staring at 21:51:50 UT on Nov. 28th, 22.4347 
hr after the burst trigger.

The optical afterglow is clearly detected in the frame. The magnitude is 
R=18.95+/-0.04, calibrated with the reference star #0710-0025176 
(R2=14.02) in the USNO B1 catalog. Comparison with our previous 
observation (Xu et al., GCN 10196) indicates a decay slope of ~0.8 
between the two epochs.


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10206
SUBJECT: GRB 091127: LABOCA/APEX submm observations
DATE:    09/11/28 23:19:44 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (INAF-OAB), A. Lundgren,
C. de Breuck, F. Montenegro and C. Agurto (ESO),
J. Gorosabel, M. Jelinek, A.J. Castro-Tirado,
P. Kubanek (IAA-CSIC), S. Covino, C.C. Thoene
(INAF-OAB) report on behalf of a larger collaboration:

"We have observed the field of GRB 091127 (Troja et al.,
GCN 10191) using LABOCA/APEX from Chajnantor (Chile) at
870 um. The observations began at 02:54 UT of the 28th
Nov (3.48 hours after the burst) and lasted for ~3 hours.
Sky conditions were mediocre, with PWV~1.5mm and
tau~0.26. The image has an r.m.s. of 4.5mJy. In the
preliminary analysis there is no source detected at the
position of the optical afterglow (Smith et al. GCN 10192).

Further observations are foreseen.

This message may be quoted."


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10207
SUBJECT: GRB 091127: optical observations
DATE:    09/11/29 12:56:34 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the optical afterglow (Smith et al. GCN 10192) of the Swift GRB 
091127 (Troja  et al. GCN 10191) with the Z-600 telescope of Mt.Terskol 
observatory in R-filter  on  Nov 28. In a combined images we clearly detect 
the afterglow.

The photometry is based on the reference star used in GCN 10205  (the star 
#0710-0025176 of the USNO B1 catalog, assuming  R2=14.02):

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

0.7981 R 10x180  18.60 +/- 0.10
0.9141 R 10x180  18.90 +/- 0.15

The photometry confirms the a global decay slope of ~0.8 within the first 
day after burst (Xu et al. GCN  10205).


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10208
SUBJECT: GRB 091127: TAROT La Silla observatory optical observations
DATE:    09/11/29 16:48:23 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

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

We imaged the field of GRB 091127 detected by Swift
(trigger 377179) with the TAROT robotic telescope (D=25cm)
located at the European Southern Observatory,
La Silla observatory, Chile.

We performed images between
1.12 and 1.37 day after the trigger using a R filter.
We do not see the OT after co-addition of all images.
The limiting magnitude is R=20.0.


GRB_name: GRB091127A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10209
SUBJECT: Konus-Wind observation of GRB 091127
DATE:    09/11/30 12:11:49 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 091127 (Swift-BAT trigger #377179:
Troja et al., GCN 10191; Stamatikos et al., 10197)
triggered Konus-Wind at T0=84349.449 s UT (23:25:49.449).

The burst light curve consists of two main peaks, and a third, softer
peak. A total duration of the burst ~10 s. The Konus-Wind light
curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB091127_T84349/

As observed by Konus-Wind the burst
had a fluence of 1.22(+/-0.06)x10-5 erg/cm2,
and a 64-ms peak flux measured from T0 + 0.256s
of 8.3(+/-0.1)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+8.448 s) is well fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), with
alpha = -1.95(-0.1, +0.1),
and Ep = 21.3(-3, +4) keV (chi2 = 57/58 dof).

The spectrum of the most intense peak (measured
from T0 to T0+0.256 s) is also well fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -1.6(-0.2, +0.2),
and Ep = 130(-32, +41) keV (chi2 = 16/27 dof).

Assuming z = 0.49 (Cucchiara et al., GCN 10202) and
a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, Omega_Lambda = 0.73,
the isotropic energy release E_iso ~7.7x10^51 erg,
the peak luminosity (L_iso)_max ~7.8x10^51 erg/s.

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


GRB_name: GRB091128A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10210
SUBJECT: GRB 091128: Fermi GBM detection
DATE:    09/11/30 14:03:42 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: 

"At 06:50:34.64 UT on 28 November 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091128 (trigger 281083836 / 091128285).

The on-ground calculated location, using the GBM trigger 
data, is RA = 127.7, DEC = 1.7 (J2000 degrees, 
equivalent to 08h 30m, 01d 42'), with an uncertainty 
of 1.4 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 96 degrees.

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

The GBM light curve shows one structured peak 
with a duration (T90) of 97.0 +/- 1.6 s (8-1000 keV). 
The time-averaged spectrum from T0-24.832 s to T0+71.425 s is
best fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.99 +/- 0.02 
and the cutoff energy, parameterized as Epeak, is 178.8 +/- 5.6 keV
(C-stat 495 for 238 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(37.6 +/- 0.7)E-06  erg/cm^2. The 1.024-sec peak photon flux measured 
starting from T0+6.912 s in the 8-1000 keV band 
is 9.3 +/- 0.3 ph/s/cm^2.

A Band function fits the spectrum equally well (C-stat 495 for 237 d.o.f.) 
with Epeak= 177.4 +/- 6.4 keV, alpha = -0.99 +/- 0.02 and beta = -3.9 +/-
1.5. 

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


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10211
SUBJECT: GRB 091127: Radio observations
DATE:    09/11/30 15:07:22 GMT
FROM:    Dale A. Frail at NRAO  <dfrail@nrao.edu>

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

"We used the Very Large Array (VLA) to observe the field of view
towards the Swift burst GRB 091127 (GCN 10197, 10199, 10201) at a
frequency of 8.46 GHz. Data was taken at two epochs: November 29.22
and November 30.21 UT. No radio source was detected at the position of
the optical afterglow with typical 3-sigma upper limits of 300 uJy. A
bright double-radio source in the field makes deeper observations
difficult. No further observations are planned.

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


GRB_name: GRB091130A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10212
SUBJECT: GRB 091130: Swift detection of a possible burst
DATE:    09/11/30 16:33:57 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
D. N. Burrows (PSU), S. Campana (INAF-OAB),
J. R. Cummings (NASA/UMBC), P.A. Curran (MSSL-UCL), V. D'Elia (ASDC),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC),
E. A. Hoversten (PSU), J. A. Kennea (PSU), N. P. M. Kuin (MSSL),
V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB),
F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),
C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL),
J. L. Racusin (NASA/GSFC), P. Romano (INAF-IASFPA),
T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-IASFPA),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC),
E. Troja (NASA/GSFC/ORAU) and T. N. Ukwatta (GSFC/GWU) report on
behalf of the Swift Team:

At 16:08:10 UT, the Swift Burst Alert Telescope (BAT) triggered and
located possible GRB 091130 (trigger=377436).  Swift did not immediately slew
to this burst due to the Earth limb constraint. 
The BAT on-board calculated location is 
RA, Dec 161.881, +11.626 which is 
   RA(J2000) = 10h 47m 32s
   Dec(J2000) = +11d 37' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is typical for an image trigger, the
light curve shows no obvious burst-like structure. 

Due to an observing constraint, Swift will not slew until 
T0+49.3 minutes. There will be no XRT or UVOT data until
this time. 

Without observations by XRT or UVOT, without a clear light curve,
and with only a marginal (7.13 sigma) image, we cannot confirm
at this time that this is a true GRB.  This uncertainty will be
resolved if the XRT detects a source during its observation,
or when the full BAT data is downlinked via Malindi. 

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


GRB_name: GRB091130A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10213
SUBJECT: GRB 091130: MASTER observations 
DATE:    09/11/30 17:50:28 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

S.Sergienko, V.Yurkov
Blagoveschensk Educational State University, Blagoveschensk


E. Gorbovskoy, D. Zimnukhov, V. Lipunov, V.Kornilov, A.Belinski, 
D.Kuvshinov,  N.Shatskiy,  N.Tyurina, P.Balanutsa, V.V.Chazov,
A.Kuznetsov

Sternberg Astronomical Institute, Moscow State University

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

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

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


MASTER  robotic telescope (MASTER-Net: http://observ.pereplet.ru, D= 200 
mm, FOV= 7  square degrees, 16 Mpx Apogee CCD, testing mode) located
at Blagoveschensk   was responted to the  GRB 091130
(Krimm et al., GCN 10212)   23 sec after Notice time and
7 min 22 s after the GRB time.

The first images are saturated due to the Moon light and cloudes.

After exposition correction we took several dozens succesfull images with 
limit ~14.5 mag.

   Time         T_start-T_GRB      ExpTime  m_lim

  16:43:56        35:45             60s       14.5

  16:43:56      35:45-47:03       10x60s      16

We do not see OT brighter 14 mag  in BAT error box.

The reduction is continued.

The message may be cited.
The summ of the images is available at 
http://observ.pereplet.ru/images/GRB091130/grb091130.jpeg.
We note that MASTER-Amur-Blagoveschensk are in testing mode now.

mailto: lipunov@sai.msu.ru


GRB_name: GRB091130B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10214
SUBJECT: GRB 091130B: Swift detection of a burst
DATE:    09/11/30 18:09:29 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. L. Racusin (NASA/GSFC), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), J. R. Cummings (NASA/UMBC),
P. A. Evans (U Leicester), S. T. Holland (CRESST/USRA/GSFC),
E. A. Hoversten (PSU), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), J. Mao (INAF-OAB),
R. Margutti (Univ Bicocca&OAB), F. E. Marshall (NASA/GSFC),
C. Pagani (PSU), K. L. Page (U Leicester), T. Sakamoto (NASA/UMBC),
M. H. Siegel (PSU), E. Troja (NASA/GSFC/ORAU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 17:59:04 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091130B (trigger=377487).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 203.098, +34.075 which is 
   RA(J2000)  =  13h 32m 24s
   Dec(J2000) = +34d 04' 31"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows two, possibly three, peaks
with a total duration of about 100 sec.  The peak count rate
was ~1800 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 18:00:30.2 UT, 85.4 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 203.1487, +34.0883 which is equivalent to:
   RA(J2000)  = 13h 32m 35.68s
   Dec(J2000) = +34d 05' 17.8"
with an uncertainty of 4.8 arcseconds (radius, 90% containment). 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 5.45e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 136 seconds with the White filter
starting 94 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. L. Racusin (judith.racusin 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: GRB091130B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10215
SUBJECT: GRB 091130B: SDSS galaxy at XRT location
DATE:    09/11/30 18:24:12 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (U. Warwick), N.R. Tanvir (U. Leicester) report:

"Inspection of SDSS images of GRB 091130B (Racusin et al. GCN 10214)
shows a faint galaxy (r=22.5),  inside the XRT localization.
There is also a brighter galaxy (r=18.9) offset roughly 7" from the
XRT position (which has a 4.8" error radius). The detection of these
objects suggests that GRB 091130B could be a relatively low redshift
event."


GRB_name: GRB091130B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10216
SUBJECT: GRB 091130B: MASTER observations 
DATE:    09/11/30 18:25:05 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

S.Sergienko, V.Yurkov
Blagoveschensk Educational State University, Blagoveschensk


E. Gorbovskoy, D. Zimnukhov, V. Lipunov, V.Kornilov, A.Belinski, D.Kuvshinov, 
N.Shatskiy,  N.Tyurina, P.Balanutsa, V.V.Chazov,
A.Kuznetsov

Sternberg Astronomical Institute, Moscow State University

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

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

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


MASTER  robotic telescope (MASTER-Net: http://observ.pereplet.ru, D= 200 mm, 
FOV= 7  square degrees, 16 Mpx Apogee CCD, testing mode) located
at Blagoveschensk   was responted to the  GRB 091130B
(Racusin et al., GCN 10214)   40 sec after Notice time and
65 s after the GRB time.
The exposition of the first image is 10s.

We do not see OT brighter 15 mag  at the Swift XRT position.

The reduction is continued.

The message may be cited.

We note that MASTER-Amur-Blagoveschensk are in testing mode now.

mailto: lipunov@sai.msu.ru


GRB_name: GRB091130A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10217
SUBJECT: Swift trigger 377436 (possible GRB 091130A) is not a burst 
DATE:    09/11/30 22:38:10 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), J. R. Cummings (CRESST/GSFC/UMBC),
E. Hoversten (PSU), on behalf of the Swift team.

Using the Swift/BAT data set from T-60 to T+236 sec and the
XRT data set beginning at T+58 minutes from recent telemetry
downlinks, we report that BAT trigger 356516 (reported as
possible GRB 091130A, Krimm et al, Circ 10212) is probably
not a GRB.  We base this conclusion on the low significance
in the BAT and the lack of a counterpart in the XRT.
However, we can not rule out that this is an astrophysical
event which was extended in duration in the BAT (the
original trigger was a 400-sec integration), but rapidly
fading prior to the XRT observations.

The BAT image shows a 3.5 sigma bump and the mask-weighted
light curve shows an integrated 5-sigma positive excess out
to T+236 sec.  If the source is real, it is at RA, Dec =
161.854, +11.580 deg with an uncertainty of 4.5 arcmin,
(radius, sys+stat, 90% containment). The partial coding is 97%.

In 2.57 ks of Swift-XRT photon counting mode data beginning
at T+58 minutes, we do not detect any X-ray source in the
BAT error circle to a 3 sigma upper limit count rate
of 8.0e-3 count/s. This corresponds to a  0.3-10 keV
observed flux limit of 3.1e-13 erg cm-2 s-1, assuming a
typical counts-to-flux conversion factor
of 3.9e-11 erg cm-2 count-1.

UVOT took a finding chart exposure of 150 seconds with
the White filter starting 3592 seconds after the BAT trigger.
No credible afterglow candidate has been found in the initial
data products. The 2.7'x 2.7' 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 0.03.


GRB_name: GRB091130B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10218
SUBJECT: GRB 091130B: Enhanced Swift-XRT position
DATE:    09/12/01 00:23:39 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 3970 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 091130B, 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 = 203.14844, +34.08839 which is equivalent
to:

RA (J2000): 13h 32m 35.63s
Dec (J2000): +34d 05' 18.2"

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: GRB091127A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10219
SUBJECT: GRB 091127: Skynet/PROMPT Observations of Fading
DATE:    09/12/01 03:28:42 GMT
FROM:    Josh Haislip at U.North Carolina  <haislip@physics.unc.edu>

J. Haislip, D. Reichart, K. Ivarsen, A. LaCluyze, L. Cominsky, K. McLin, T. 
Graves, G. Spear, R. Egger, A. Foster, J. Moore,
A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. Nysewander 
report:

Skynet observed the Swift/BAT localization of GRB 091018 (Troja et al., GCN 
10191) with five of the 16" PROMPT telescopes at
CTIO beginning 61.6 minutes after the trigger in BVRI.

Skynet continued observing with the 14" GORT telescope at Hume Observatory 
in California beginning 27.8 hours after the
trigger in RI.

We detect the afterglow (Smith et al., GCN 10192) in all filters.

Similar to GRB 091018 (LaCluyze et al., GCN 10046), the afterglow faded 
more slowly in the red bands than in the blue bands
over the course of the first night.

Between 1 and 4 hours after the trigger, the afterglow faded with a 
power-law index of about -0.4 in I and about -0.5 in B.
Between 4 and 9 hours after the trigger, the afterglow faded with a 
power-law index of about -0.9 in I and about -1.1 in B.
Overall, I - B brightened by about 0.25 mag over the course of 8 hours.

Between 9 and 33 hours after the trigger, the afterglow faded with a 
power-law index of about -1.2 in all bands.

At 32.2 hours after the trigger, the afterglow's magnitude was R = 19.39 
+/- 0.06 (statistical) +/- 0.37 (systematic;
calibrated to 102 USNO B1 stars).

Skynet's most recent BVRI light curve, calibrated to USNO B1 and NOMAD 
stars, can be found here:

http://skynet.unc.edu/grb/grb091127.png


GRB_name: GRB091130B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10220
SUBJECT: GRB 091130B: Swift/UVOT Upper Limits
DATE:    09/12/01 05:22:33 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) and J. L. Racusin (NASA/GSFC) report on behalf
of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 091130B
95s after the BAT trigger (Racusin et al., GCN 10214). We do not
detect any source at the enhanced Swift XRT position (Goad et al. GCN
10218). UVOT magnitude 3-sigma upper limits are reported in the
following table:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white       95       230     132        > 20.20
white     4517      4717     196        > 20.97
v         3492      3692     196        > 19.38
b         4313      4512     196        > 20.31
u         4107      4307     196        > 19.91
uvw1      3903      4102     196        > 19.88
uvm2      3697      3897     196        > 19.76
uvw2      4723      4923     196        > 19.98

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


GRB_name: GRB091130B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10221
SUBJECT: GRB 091130B: Swift-BAT refined analysis
DATE:    09/12/01 05:44:50 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

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

Using the data set from T-60 to T+243 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 091130B (trigger #377487)
(Racusin, et al., GCN Circ. 10214).  The BAT ground-calculated position
is RA, Dec = 203.149, 34.086 deg which is
    RA(J2000)  =  13h 32m 35.8s
    Dec(J2000) = +34d 05' 11.0"
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 77%.

The mask-weighted light curve shows several broad, irregular, 
overlapping peaks starting at T-25 sec, peaking at T0 and ending
about T+120 sec.  T90 (15-350 keV) is 112.5 +- 17.1 sec (estimated
error including systematics).

The time-averaged spectrum from T-4.7 to T+127.4 sec is best fit by a
simple power-law model.  The power law index of the time-averaged 
spectrum is 2.15 +- 0.15.  The fluence in the 15-150 keV band is
1.3 +- 0.1 x 10^-06 erg/cm2.  The 1-sec peak photon flux measured from
T-0.06 sec in the 15-150 keV band is 1.1 +- 0.2 ph/cm2/sec.  All the quoted
errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/377487/BA/

[GCN OPS NOTE(01dec09): Changed "091130" to "091130B".]


GRB_name: GRB091130B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10222
SUBJECT: GRB 091130B: Swift-XRT team refined analysis
DATE:    09/12/01 07:37:46 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page (U. Leicester) and J. L. Racusin (NASA/GSFC) report on behalf of 
the Swift-XRT team: 

We have analysed 12 ks of XRT data for GRB 091130B (Racusin et al. GCN 
Circ. 10214), from 91 s to 29.1 ks after the BAT trigger. The data 
comprise 155 s in Windowed Timing (WT) mode with the remainder in Photon 
Counting (PC) mode. The enhanced XRT position for this burst was given by 
Goad et al. (GCN. Circ 10218).

The light curve can be modelled with a series of power-law decays. The 
initial index is alpha=-0.36 (+0.87, -1.14) - i.e., the light curve rises 
slightly. At T+107 s the light curve starts decaying with an alpha of 3.58 
(+0.24, -0.17). The light curve breaks again at T+172 s to a decay with 
alpha=2.11 (+0.24, -0.06), before a final break at T+4020 s, after which 
the decay index is 0.32 (+0.10, -0.11).

A spectrum formed from the WT mode data can be fitted with an absorbed 
power-law with a photon spectral index of 2.26 (+0.07, -0.06). The 
best-fitting absorption column is 2.32 (+/-0.17) x 10^21 cm^-2, in excess 
of the Galactic value of 8.0 x 10^19 cm^-2 (Kalberla et al. 2005). The PC 
mode spectrum has a photon index of 2.48 (+0.18, -0.19) and a best-fitting 
absorption column of 1.66 (+0.23, -0.43) x 10^21 cm^-2. The counts to 
observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this 
spectrum is 3.2 x 10^-11 (5.8 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 
0.32, the count rate at T+24 hours will be 0.030 count s^-1, corresponding 
to an observed (unabsorbed) 0.3-10 keV flux of 9.6 x 10^-13 (1.7 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/00377487.

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


GRB_name: GRB091126A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10223
SUBJECT: GRB 091126: Fermi GBM detection
DATE:    09/12/01 10:18:21 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

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

"At 07:59:24.76 UT on 26 November 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091126 (trigger 280915166 / 091126333).
The on-ground calculated location, using the GBM trigger
data, is RA = 83.3, DEC = -19.3 (J2000 degrees,
equivalent to 05 h 33 m, -19 d 18 '), with an uncertainty
of 5.4 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 93 degrees.
This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of one pulse
with a duration of about 0.3 s (8-1000 keV).
The time-averaged spectrum from T0-0.256 s to T0+0.256 s is
adequately a power law function with an exponential
high energy cutoff.  The power law index is -0.60 (+0.24/-0.21) and
the cutoff energy, parameterized as Epeak, is 458 (+215/-107) keV
(CSTAT  478 for 476 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(5.9 +/- 0.5)E-7 erg/cm^2. The 0.128 sec peak photon flux measured
starting from T0+0 s in the 8-1000 keV band
is 8.3 +/- 0.7 ph/s/cm^2.

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


GRB_name: GRB091127A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10224
SUBJECT: GRB 091127: Suzaku WAM observation of the prompt emission
DATE:    09/12/01 13:01:32 GMT
FROM:    Yusuke Nishioka at Miyazaki U.  <yusuke613@astro.miyazaki-u.ac.jp>

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

 
 The long GRB 091127 (Swift/BAT trigger #377179 ; Stamatikos et al., 
 GCN 10197; Fermi/GBM trigger #281057147 ; Colleen et al., GCN 10204)  
 triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers an 
 energy range of 50 keV - 5 MeV at 2009-11-27 23:25:45.155 UT (=T0).


 The observed light curve shows a double-peaked structure starting at T0 s, 
 ending at T0+11 s with a duration (T90) of about 7 seconds. 
 The fluence in 100 - 1000 keV was 7.35 (-0.50, +0.43) x10^-6 erg/cm^2. 
 The 1-s peak flux measured from T0+1 s was 8.94 (-0.70, +0.56) 
 photons/cm^2/s in the same energy range.

 Preliminary result shows that the time-averaged spectrum from T0 s to 
 T0+11 s is well fitted by a single power-law with a photon index of 
 2.33 (-0.12, +0.13) (chi^2/d.o.f = 46.3/34).

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

 The light curves for this burst are available at:

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


GRB_name: GRB091126B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10225
SUBJECT: GRB 091126B: Fermi GBM detection
DATE:    09/12/01 16:57:03 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

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

"At 09:19:48.53 UT on 26 November 2009, the Fermi Gamma-Ray
Burst Monitor triggered and located a short burst GRB 091126B
(trigger 280919990/091126389).
The on-ground calculated location, using the GBM trigger
data, is RA = 47.4, DEC = 31.5 (J2000 degrees,
equivalent to 03 h 10 m, 31 d 30 '), with an uncertainty
of 14.3 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 60 degrees.
This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of one pulse
with a duration of about 30 ms (8-1000 keV).
The time-averaged spectrum from T0-0.016 s to T0+0.016 s is
adequately  fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.23 (+0.32/-0.23) and
the cutoff energy, parameterized as Epeak, is 731 (+229/-165) keV
(CSTAT 753 for 846 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(2.2 +/- 0.02)E-07 erg/cm^2. The 16 ms peak photon flux measured
starting from T0-0.008 s in the 8-1000 keV band
is 20.5 +/- 1.3  ph/s/cm^2.

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


GRB_name: GRB091123A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10226
SUBJECT: GRB 091123: Fermi GBM detection of a very long burst
DATE:    09/12/01 18:16:00 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

S. McBreen (UCD/MPE), V. Connaughton (UAH), C. Wilson-Hodge (NASA MSFC),
M. Finger (USRA) and D. Tierney (UCD) report on behalf of the Fermi GBM Team:

"At 07:08:37.26 UT on 23 November 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091123 (trigger 280652919 / 091123298).
The on-ground calculated location, using the GBM trigger
data, is RA = 297.1, DEC = -29.2 (J2000 degrees,
equivalent to 19 h 48 m, -29 d 12'), with an uncertainty
of 2.4 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 106 degrees.
This burst was also independently detected by INTEGRAL SPI-ACS
and Konus-Wind.

The GBM light curve consists of 4 main emission phases,
each containing structure, separated by long periods of quiescence.
Comparison with Konus-Wind data shows that the the event was
already on-going when when it rose above the Earth's horizon.
This allows a further constraint to be placed on the possible
arrival direction of this burst. A plot showing the 3-sigma
localization contours (statistical only) and the limb of
the Earth at T0, T0-5, and T0+5 s is available at:

http://gammaray.nsstc.nasa.gov/gbm/science/loc_091123298.gif


In the GBM data alone, the burst has  a duration of at least
650 sec (8-1000 keV).

The time-averaged spectrum from T0-5 s to T0+650 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.08 +/- 0.05 and
the cutoff energy, parameterized as Epeak, is 101.30 (+5.16/-4.52) keV
(C-stat 1008 for 355 d.o.f.). There is significant spectral
evolution within the fitted time interval.

The event fluence (8-1000 keV) in this time interval is
(4.07 +/- 0.09)E-05erg/cm^2. The 1-sec peak photon flux measured
starting from T0+11.2 s in the 8-1000 keV band
is 6.1 +/- 0.2 ph/s/cm^2.

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

We thank Valentin Pal'shin for providing the Konus-Wind
lightcurves and informing us of the burst occultation by
the Earth before the GBM trigger time.


GRB_name: GRB091130A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10227
SUBJECT: GRB 091130A: Xinglong TNT upper limit
DATE:    09/12/02 06:54:04 GMT
FROM:    L.P. Xin at NAOC  <xlp@bao.ac.cn>

Y.L. Qiu, X.F. Wang, C. Wu, L.P. Xin,  J. Wang, 
J.Y. Wei, W. K. Zheng, J. S. Deng, and J. Y. Hu 
on behalf of EAFON report:

We observed the optical afterglow of GRB 091130A
(Krimm et al. GCN 10212) with Xinglong TNT telescope 
from Nov. 30th, 18:25:41 (UT), 2.27 hours after the burst. 
The weather is not good with a bright moon. 
After stacked 31*300s images, the 3 sigma upper limit 
is estimated to be R-21 mag from the SDSS magnitude, 
at the meam time of 4.2 hours after the burst.

This message may be cited.  

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


GRB_name: GRB091123A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10228
SUBJECT: Konus-Wind observation of very long GRB 091123
DATE:    09/12/02 15:22:37 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

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

A very long GRB 091123 was detected by Konus-Wind in the waiting mode at 
~T0=25585 s UT (07:06:25). The most part of the burst was also detected 
and localized by Fermi-GBM, while it missed the first ~130 s due to the 
Earth occultation (McBreen et al., GCN 10226).

The burst light curve shows several pulses with a total duration of ~800 s.

As observed by Konus-Wind, the burst had a fluence of (8.3 +/-
0.8)x10^-5 erg/cm2 (in the 20 - 1300 keV energy range).

Modeling the K-W 3-channel time-integrated spectrum (from T0 to T0+806 
s) by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -1.49 +/- 0.36, Ep = 243 +/- 80 keV.
The 3-channel spectrum of the most intense pulse
(from T0+100 s to T0+150 s) can be modeled by a power law with 
exponential cutoff model with alpha = -1.03 +/- 0.11, Ep = 293 +/- 35 
keV. The fluence of this pulse is (3.17 +/- 0.16)x10^-5 erg/cm2.

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

The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB091123/


GRB_name: GRB091127A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10230
SUBJECT: GRB 091127: Skynet/PROMPT Continued Observations of Fading
DATE:    09/12/02 17:34:10 GMT
FROM:    Josh Haislip at U.North Carolina  <haislip@physics.unc.edu>

J. Haislip, D. Reichart, K. Ivarsen, A. LaCluyze, R. Egger, A. Foster, J. 
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. 
Nysewander report:

Skynet continued to observe the afterglow (Smith et al., GCN 10192) of GRB 
091127 (Troja et al., GCN 10191) with four of the 16" PROMPT telescopes at 
CTIO in BVRI.

The light curve (Haislip et al., GCN 10107) continued to roll over. Between 
25.0 hours and 3.4 days after the trigger, the afterglow faded with a 
power-law index of about -1.4 in all bands.

At 3.2 days after the trigger, the afterglow's magnitude was R = 20.71 
+0.15 -0.13 (statistical) +/-  0.37 (systematic; calibrated to 102 USNO B1 
stars).

Skynet's most recent BVRI light curve, calibrated to USNO B1 and NOMAD 
stars, can be found here:

http://skynet.unc.edu/grb/grb091127.png


GRB_name: GRB091020A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10231
SUBJECT: GRB 091020: MASTER-Net  optical polarization observations 
DATE:    09/12/02 19:15:38 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

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

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

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

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

S.Sergienko, V.Yurkov
Blagoveschensk Educational State University, Blagoveschensk

MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru, 2x400
mm, 2x 4 square degrees, 2x16Mpx Apogee CCD) located
at Kislovodsk  was pointed to the  GRB 091020 (Racusin et al., GCN 10048)
by internet   3422 s after the GRB time. The
large delay  was caused with   technical problems on site (Gorbovskoy et 
al., GCN 10052).

The first 7 images was taken in R-band. The exposure each images is 180s.

West-telescope
GRB Time         OT Mag         Error
1.02097639      17.93           0.22
1.07643278      17.43           0.09
1.13188834      17.78           0.14
1.18734417      18.03           0.19
1.24280056      17.87           0.15
1.29825584      17.58           0.10
1.35371584      17.94           0.12

The result of the unfiltred polarization combined images is:

West-telescope
GRB Time         OT Mag         Error
(Hours)

1.604558        18.65           0.10
1.983004        18.91           0.08
2.285582        19.04           0.08
2.562864        19.28           0.11
2.84015         19.36           0.09
3.117435        19.32           0.08
3.394721        19.35           0.06
3.672004        19.23           0.10
3.949285        20.07           0.16
4.226602        20.67           0.28
4.503883        20.07           0.22



East-telescope

GRB Time          GRB           Error
(Hours)

1.604718        18.60           0.06
1.983232        18.46           0.06
2.285826        19.14           0.09
2.563109        19.11           0.09
2.84039         19.56           0.10
3.117671        19.38           0.09
3.394954        19.70           0.17
3.672234        19.53           0.11
3.949516        19.92           0.16
4.226796        20.03           0.19
4.50408         19.99           0.16

Using all our polarizated magnitudes we
find that the  light curve is very well described by a
single power-law decay with alpha = 1.2 +/- 0.1, that is in good agreement
with the following observations (Kann et al., GCN 10076)


The light curve of our observations is available at
http://observ.pereplet.ru/images/GRB091020/grb.html  .
The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB091117A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10232
SUBJECT: GRB 091117:  Chandra Observations 
DATE:    09/12/02 19:36:40 GMT
FROM:    Derek Fox at PSU  <dfox@astro.psu.edu>

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

"We observed the Swift/BAT localization region for GRB 091117
(Cummings et al., GCN 10171; Sakamoto et al., GCN 10180) with the
Chandra X-ray Observatory + ACIS, positioned at the ACIS-S3 aimpoint,
in a 20.1 ksec integration with mean epoch Nov 21.85 UT, 4.1 days
after the burst trigger.

Analysis of these data reveals the presence of nine X-ray sources
within and near the BAT localization region, including the two X-ray
sources identified in previous Swift XRT observations (Berger, GCN
10173; D'Elia et al., GCN 10177).  Comparison to deep optical imaging
of the region from Magellan (Berger & Mulchaey, GCN 10174; Berger &
Momcheva, GCN 10183) reveals point-like (nuclear, stellar, or
unresolved galactic) optical counterparts to all but three of these
sources:

    #      CXOU J         Sigma    Cts  Unc   Comments
   ==========================================================
    1  020353.36-165830.0  54.0  119    11    XRT-1; Nuclear
    2  020356.65-165659.1  44.5  101    10    XRT-2; Nuclear
    3  020353.68-165428.1  14.7   34.9  6.5   Stellar
    4  020338.35-165547.3   8.7   23.0  5.0   Stellar
    5  020347.45-165927.6   6.2   13.4  3.7   (not imaged)
    6  020342.46-165706.7   4.8    9.7  3.2   Stellar
    7  020345.74-165817.1   4.2    8.7  3.0   Near galaxy
    8  020345.21-165818.2   3.8    7.7  2.8   Stellar
    9  020349.61-165430.5   3.7    7.6  2.8   No counterpart
   ==========================================================

The table above provides source names/coordinates (J2000) as
determined from the Chandra astrometric solution, the significance of
detection in "wavdetect" analysis over the 0.3-8.0 keV bandpass, and
estimated counts and uncertainties (0.3-8.0 keV) for each source. The
nature of the optical counterpart, if any, is also provided.

We note that the two brightest X-ray sources, also observed by Swift,
are coincident to within <1 arcsec with the active nuclei of the two
brightest galaxies in the region: Chandra source #1 (XRT-1) with the
active nucleus of the face-on spiral galaxy at z=0.096 (Chornock &
Berger, GCN 10176), and Chandra source #2 (XRT-2) with the active
nucleus of 2MASX J02035665-1656585 at z=0.092.  Source #1 appears
(2.8-sigma confidence) to have faded since the first epoch of Swift
observations, consistent with inferences from Swift XRT data (Fox, GCN
10179); however, the coincidence of sources #1 and #2 with AGN
suggests that neither of these objects is associated with GRB 091117.

Chandra source #7 is notable for being located 2.4 arcsec from the
center of an edge-on galaxy that is resolved in our Magellan imaging."


GRB_name: GRB091127A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10233
SUBJECT: GRB 091127: redshift confirmation with X-shooter
DATE:    09/12/02 23:41:17 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

C.C. Thoene (INAF-OAB), P. Goldoni (APC/Univ. Paris 7 and SAp/CEA)
S. Covino (INAF-OAB), L.A. Antonelli (INAF-OAR), D. Malesani, J.P.U.
Fynbo (DARK/NBI), A.J. Levan (U. Warwick), P. Jakobsson (U. Iceland),
H. Flores (Paris Obs.), B. Milvang-Jensen, J. Hjorth, D. Watson (DARK/NBI),
K. Wiersema, N. R. Tanvir (Univ. Leicester), A. de Ugarte Postigo
(INAF-OAB) report on behalf of the X-shooter GRB collaboration:

We observed the afterglow of GRB 091127 (Troja et al. GCN 10191, Smith
et al. GCN 10192) with X-shooter at the VLT starting at 03:17 UT on
Dec 2, 2009. The observation consisted of  4x1500s exposures,  with a
mean epoch 4.2 days after the burst when the magnitude of the
afterglow was R ~ 21 mag (Haislip et al. GCN 10230). We detect the
continuum in the range from 3400 to 24800 Angstrom. The S/N in the blue
part of the spectrum is low due to the effect of the nearby Moon.

In a preliminary analysis using an archival wavelength calibration we
detect several emission features superimposed on the afterglow
continuum, namely [OII] (3727, 3729), H-beta (4863), [OIII]  (4960,
5007) and H-alpha (6563) at a common redshift of 0.49034 +/- 0.00018.
This redshift is consistent with the observations reported by
Cucchiara et al. (GCN 10202). We do not detect any obvious absorption
features at that redshift.

We thank the ESO observing staff, in particular H. Korhonen and S. Stefl.


GRB_name: GRB091202A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10234
SUBJECT: GRB 091202: a long GRB detected by INTEGRAL
DATE:    09/12/03 00:10:48 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

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

A  GRB with duration of about 50  s has been detected by IBAS in
IBIS/ISGRI data at 23:10:12 UT on December 2nd.

The refined coordinates (J2000) are:

RA: 138.8312 [degrees]  
DEC: 62.544  [degrees]

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

A plot of the light curve will be posted at

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

This message can be cited.


GRB_name: GRB091202A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10235
SUBJECT: GRB 091202: Liverpool Telescope Observations
DATE:    09/12/03 02:14:13 GMT
FROM:    Carole Mundell at ARI, JMU,Liverpool  <cgm@astro.livjm.ac.uk>

C.G. Mundell (Liverpool, JMU) reports on behalf of a larger collaboration:

"The 2-m Liverpool Telescope robotically followed up GRB091202
(INTEGRAL trigger 5957; Mereghetti et al. GCN 10234) 60.93 min after
the GRB trigger time.

Preliminary analysis shows no uncatalogued source within a 4.6-arcmin 
diameter error box centred on the INTEGRAL position to a limiting 
magnitude i'~19 mag (vs USNOB1).

We note the presence of a faint galaxy centred at the INTEGRAL position:
http://cas.sdss.org/dr7/en/tools/explore/obj.asp?id=587737809576592135

This message may be cited"


GRB_name: GRB091202A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10236
SUBJECT: GRB 091202: TAROT Calern observatory optical observations
DATE:    09/12/03 02:26:46 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

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

We imaged the field of GRB 091202 detected by INTEGRAL
(trigger 5957) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 35s after the GRB trigger.
The elevation of the field increased from
45 degrees above horizon and weather conditions
were poor (full moon at 50 deg).

The date of trigger : t0 = 2009-12-02T23:10:12
(according to Mereghetti et al. GCNC 10234).

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+35s to t0+95s : R > 13.0

The second image is 30.0s exposure in tracking mode:
t0+114s to t0+144s : R > 15.3

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction
(estimated to be 0.13 magnitudes in R band).
N.B. Galactic coordinates are lon=152.2 lat=+40.2


GRB_name: GRB091126A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10237
SUBJECT: GRB 091126A: Suzaku WAM observation of the prompt emission
DATE:    09/12/03 06:12:46 GMT
FROM:    Hidenori Hayasi at Miyazaki U  <hayasi@astro.miyazaki-u.ac.jp>

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

The short GRB 091126A (Fermi/GBM trigger #280915166 ; Tierney et al., 
GCN 10223) triggered the Suzaku Wide-band  All-sky Monitor (WAM) which 
covers an energy range of 50 keV - 5 MeV at 2009-11-26 07:59:24.67 UT (=T0)

The observed light curve shows a single peak starting at T0 , ending 
at T0+0.5 s with a duration (T90) of about 0.3 seconds.
The fluence in 100 - 1000 keV was 5.76 (-1.72,+1.47) x10^-7 erg/cm^2. 
The 1-s peak flux measured from T0  was 1.57 (-0.84,+0.39) photons/cm^2/s 
in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0 to 
T0+0.5 s is well fitted by a single power-law with a photon index 
of 2.27 (-0.43,+0.55) (chi^2/d.o.f. = 20/16).

The power-law with exponential cutoff model also gives a good fit with  
the Epeak of 303(-99,+151) keV, assuming the power-law index of -0.6 as  
was reported by Tierney et al. (GCN 10223).

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

The light curves for this burst are available at:

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


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10238
SUBJECT: GRB 091127: Zadko Telescope Observations
DATE:    09/12/03 08:26:48 GMT
FROM:    David Coward at U of Western Aus.  <coward@physics.uwa.edu.au>

T.P. Vaalsta, D.M. Coward report on behalf of the Zadko Telescope Team.

T.P. Vaalsta,  D.M. Coward, I. Ward, J. Moore, A. Imerito, D. Blair,  
R. Burman, S. Gordon,
A. Fletcher, A. Ahmet, A. Burrell (University of Western Australia),
L. Smith (ICRAR),
M. Todd, M. Zadnik (Curtin University),
M. Boer, M. Laas-Bourez, (OHP-OAMP),
A. Klotz, P. Thierry (CESR-OMP)

The 1.0m F/4 Zadko telescope started imaging the field of GRB 091127  
(trigger=377179, D. Palmer
et al., GCN 10191) 18.5 hours after the Swift trigger. A faint source  
was found at the
reported OA location (GCN 10199, S. Immler).  The field was observed  
for 28 minutes, during
this time the moon set and weather conditions were good.

Photometry on the co-added sum of four CCD images of total exposure  
time of 806s gives
a magnitude of 18.9 +/- 0.1 for the optical counterpart.


GRB_name: GRB091202A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10239
SUBJECT: GRB 091202 - UVOT-enhanced XRT position
DATE:    09/12/03 12:19:18 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

L. Vetere (PSU), P.A. Evans and M.R. Goad (U. Leicester) report
on behalf of the Swift-XRT team:

Using 1511 s of XRT Photon Counting mode data and 1 UVOT
images, we find an astrometrically corrected X-ray position (using the
XRT-UVOT alignment and matching UVOT field sources to the USNO-B1
catalogue): RA, Dec =138.83400, 62.54950 which is equivalent to:

RA (J2000):  09 15 20.17
Dec (J2000): +62 32 58.1

with an uncertainty of 3.4 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 is an official product of the Swift-XRT team.


GRB_name: GRB091202A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10240
SUBJECT: GRB 091202: Optical and NIR observations
DATE:    09/12/03 12:27:22 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (INAF-OAB), A.J. Castro-Tirado, M. Jelinek,
J. Gorosabel, S. Guziy (IAA-CSIC) and R. Barrena-Delgado (IAC)
report on behalf of a larger collaboration:

"We have observed the error box of the INTEGRAL GRB 091202
(Mereghetti et al. GCN 10234) in optical using the 0.8m IAC80
telescope and in NIR using the 1.5m TCS telescope, both located
in Teide Observatory (Spain).

Optical observations began at 1:26 UT of the 3rd Dec 2009 and
included V, R and I imaging. We do not detect any new source
within the XRT error box (Vetere et al. GCN10239). In particular
in a 600s I band image with mean epoch 3.07 h after the burst
onset we do not detect any new source down to a 3-sigma limiting
magnitude of I > 19.9 as compared to USNO-B1.0 star 1525-0212637
for which we assume a magnitude of I = 18.26.

NIR observations starting at 04:03 UT were obtained with J, H
and K filters, with a total of 1000s integration each. We do not
detect any new source within the XRT error box. In particular,
we obtain a 3-sigma limiting magnitude of K > 17.0 5.12 h after
the burst as compared with the 2MASS catalogue.

This message may be cited."


GRB_name: GRB091202A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10241
SUBJECT: GRB 091202: Liverpool Telescope observations
DATE:    09/12/03 15:15:05 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>

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

On 2009 December 3 at 00:11:21 UT the 2-m Liverpool Telescope
automatically began observing the INTEGRAL GRB 091202
(Mereghetti et al., GCN Circ. 10234; Mundell GCN Circ 10235)
using the r', i' and z' filters, corresponding to 1.02 hours
after the burst.

Inside the XRT error circle (Vetere et al. GCN Circ. 10239)
we do not detect any source at the following limiting
magnitudes:

Mid time from    Total Exp   Filter    Magnitude
trigger (hr)     (s)
------------------------------------------------
1.48             360         z'        > 19.0
1.61             720         i'        > 20.7
1.49             720         r'        > 20.4
------------------------------------------------

Magnitudes have been calibrated from the following nearby
SDSS stars:

RA            Dec         z'       i'      r'
-----------------------------------------------
138.81006    +62.53208   15.16    15.24   15.41
138.82579    +62.53708   18.73    18.73   18.90
-----------------------------------------------


GRB_name: GRB091202A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10242
SUBJECT: GRB 091202: Swift/UVOT Upper Limits
DATE:    09/12/03 16:34:23 GMT
FROM:    Alice Breeveld at MSSL-UCL  <aab@mssl.ucl.ac.uk>

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

The Swift/UVOT began settled observations of the field of GRB 091202 
2363 s after the Integral trigger (Mereghetti et al., GCN Circ. 
10234). No new sources are found at the XRT position (Vetere et al., 
GCN Circ. 10239) in the initial UVOT exposures. Preliminary 3-sigma 
upper limits using the UVOT photometric system (Poole et al. 2008, 
MNRAS, 383, 627) for the initial exposures are:

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

white             3120         3869          738         >21.7
v                 3876         4357          473         >19.5
u                 2363         3113          738         >20.9

The values quoted above are not corrected for the Galactic extinction 
due to the reddening of E(B-V) = 0.051 in the direction of the burst 
(Schlegel et al. 1998).


GRB_name: GRB091202A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10243
SUBJECT: GRB091202: Swift-XRT refined analysis
DATE:    09/12/03 20:13:43 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

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

We have analysed 5.6 ks of XRT data for GRB 091202 (Mereghetti et al.
GCN Circ. 10234) from 2364 s to 26.9 ks after the BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Vetere et al. (GCN. Circ 10239).

The light curve is decaying but we do not have enough data to estimate
the decay slope and no more observations are planned at this time.

The spectrum comprises only 27 photons, but it can be fitted with an  
absorbed
power-law with a photon spectral index of 2.2 (+0.9 -0.8).  The best- 
fitting
absorption column is 2.0 (+2.9, -1.2) x 10^21 cm^-2, in excess of the  
Galactic
value of 3.9 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to  
observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this  
spectrum
is 4.2 x 10^-11 (6.4 x 10^-11) erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020123.

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


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10244
SUBJECT: GRB 091127, SMARTS optical/IR afterglow observations
DATE:    09/12/03 23:50:51 GMT
FROM:    Bethany Cobb at UC Berkeley  <bcobb@astro.berkeley.edu>

B. E. Cobb (UC Berkeley) reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained
optical/IR imaging of the error region of GRB 091127 (GCN 10191, Troja
et al.) over seven epochs with mid-exposure times between ~2.2 and 100.8 
hours post burst.

The optical afterglow of GRB 091127 (e.g. GCN 10192, Smith et al. & GCN 
10193, Immler et al., GCN 10194) is observed in our imaging.  In our first 
epoch, with a mid-exposure time of ~2.2 hours post-burst, the afterglow 
is clearly detected in our imaging with the following magnitudes:

B = 17.21 +/- 0.02 +/- 0.20 (error in zeropoint)
R = 16.70 +/- 0.02 +/- 0.23 (error in zeropoint)
I = 16.61 +/- 0.02 +/- 0.30 (error in zeropoint)
J = 15.56 +/- 0.05
H = 15.40 +/- 0.05
K = 14.77 +/- 0.05

(Optical photometry is calibrated against USNO-B1.0 stars in the field, so 
suffers from a large photometric calibration error. IR photometry is 
calibrated against 2MASS stars.)

The afterglow remains visible in our optical imaging over all our epochs 
of observation. Between 2.2 and 5.4 hours post burst, the afterglow decays 
with a  power-law of alpha ~ -0.6  (where afterglow flux is proportional 
to t^alpha).  From 27.8 to 100.8 hours post-burst, the afterglow appears 
to have steepened its decay rate to alpha ~ -1.6. This agrees with the 
behavior observed by Haislip et. al (GCNs 10219 & 10230).

mid-exposure
time (hours
post-burst) I mag
--------------------------------------------------------
   2.2  16.61 +/- 0.02  [+/- 0.30, zp error]
   3.8  16.90 +/- 0.02  [+/- 0.30, zp error]
   5.4  17.18 +/- 0.03  [+/- 0.30, zp error]
  27.8  19.28 +/- 0.03  [+/- 0.30, zp error]
  30.6  19.34 +/- 0.03  [+/- 0.30, zp error]
  51.7  21.10 +/- 0.12  [+/- 0.30, zp error]
100.8  21.38 +/- 0.07  [+/- 0.30, zp error]


GRB_name: GRB091127A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10245
SUBJECT: GRB091127: Continuing Swift/UVOT Observations
DATE:    09/12/04 14:27:58 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and E. Troja (NASA/GSFC/ORAU) report on  
behalf of the Swift/UVOT team:

After a relatively flat initial decay, the light curve of
the optical afterglow of GRB 091127 (Smith et al. GCN Circ. 10192;
Immler & Troja, GCN Circ. 10193) has steepened to a
decay index of 1.44 in UVOT observations with the white filter.
At 5.2 days after the BAT trigger (Troja et al., GCN Circ. 10191),
the white magnitude is 21.8 +/- 0.1.
Similar light curves are seen for the UVOT V and U filters.
The current decay index is close to that reported
by Haislip et al. (GCN Circ. 10230) using observations
between 25 and 77 hours after the trigger, and by
Cobb (GCN Circ. 10244) using data from 27.8 to 100.8
hours after the trigger.

UVOT observations of the afterglow are continuing.


GRB_name: GRB091109A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10246
SUBJECT: GRB 091109A: GROND confirmation of redshift z = 3.5
DATE:    09/12/04 17:32:12 GMT
FROM:    Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>

GRB 091109A: GROND confirmation of redshift z = 3.5

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

GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m ESO/MPI
telescope at La Silla Observatory (Chile), reobserved the field of GRB
091109A (Oates et al., GCN #10138) simultaneously in the g'r'i'z'JHK
bands.

Observations started 2009-11-20 00:42, 10.8 days after the trigger and
lasted for an effective exposure of 75 min in g'r'i'z' and 60 min in JHK.

At the position of the optical afterglow (Guidorzi et al. GCN#10142,
Oates GCN#10143, Afonso et al., GCN #10158) we do not detect any source
down to a limiting magnitude of r' > 25.1.

Comparing with the brightness of r' = 23.6 +- 0.1 mag (AB) reported for
the 1st epoch (Afonso et al., GCN #10158), the last imaging clearly
shows a fading of more than 1.5 magnitudes. The 1st epoch was hence
dominated by afterglow light, favoring a redshift of around z = 3.5 +/-
0.4.

A thorough analysis of the VLT data (GCN # 10158) was limited by the
very low S/N of the optical spectrum and does not yield more precise
redshift constraints.


GRB_name: GRB091202A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10247
SUBJECT: GRB 091202: GTC & CAHA optical/nIR afterglow candidate
DATE:    09/12/05 00:25:15 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

A. de Ugarte Postigo (INAF-OAB), A.J. Castro-Tirado, J. Gorosabel, M. 
Jelnek, S. Guziy (IAA-CSIC), A. Cabrera-Lavers, D. Garca, G. Gmez 
(GTC/IAC), G. Bergond (CAHA), D. Prez-Ramrez (Univ. de Jan), R. 
Cuniffe (IAA-CSIC) and P. Kubnek (IAA-CSIC, U. Valencia) report on 
behalf of a larger collaboration:

"We have observed the field of the INTEGRAL GRB 091202  (Mereghetti et 
al. GCN 10234) using OSIRIS at the 10.4m Gran Telescopio Canarias (GTC) 
at the Observatorio del Roque de los Muchachos of the Instituto de 
Astrofsica de Canarias, in the island of La Palma. Observations were 
carried out between 04:55 and 05:23 UT on 4 December 2009 (~1.25 days 
after the burst). The observation consisted of 5x30s exposures in r, i 
and z bands. Addtional near-IR observations were obtained in with 
Omega2000 at the 3.5m telescope at the German-Spanish Calar Alto 
Observatory in J, H and K' bands between 01:06 and 04:46 UT.

Within the XRT error circle (Vetere et al. GCN 10239) we detect two 
sources, one point-like and one apparently extended in all three GTC 
frames. Only one source (point-like) shows up in the near-IR frame, 
which appears to be superimposed to the extended one seen in the 
optical. This will imply a strong red colour (r-H >= 4) typical of GRB 
afterglows (Gorosabel et al. 2002, A&A 384, 11). Hence, we identify this 
source as the likely afterglow to GRB 091202, at coordinates (J2000):

R.A.:  09 15 19.75
Dec.: +62 32 59.0

with a 0".5 astrometry error.

At a mean epoch of 1.25 days after the burst, we measure for it a 
magnitude of r = 23.7  0.1. From the nIR observations we measure H = 
19.7  0.2. at a mean epoch 1.21 days after the burst. For the optical 
photometry we used the SDSS star located at coordinates R.A.: 09 15 
21.23, Dec: +62 32 33.4 (J2000) for which we assume a magnitude of r = 
21.27. The nIR images were calibrated against a 2MASS star at 
coordinates R.A.: 09 15 14.41, Dec: +62:31:55.5 (J2000) with H = 13.94.

Based on the optical GTC image, at this moment we cannot rule out that 
the optical flux arises from an underlying somehow extended blue galaxy 
whereas the highly extincted afterglow is only observed in the nIR. A 
figure showing the optical & nIR images of the likely afterglow to GRB 
091202 can be found at:  http://www.iaa.es/~gss/GRB091202

This message may be quoted."


GRB_name: GRB091127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10248
SUBJECT: GRB 091127: GAO 150cm telescope Optical Observation
DATE:    09/12/05 08:59:45 GMT
FROM:    Kenzo Kinugasa at Gunma Astro. Obs/Japan  <kinugasa@astron.pref.gunma.jp>

K. Kinugasa, S. Honda, O. Hashimoto, H. Takahashi, H. Taguchi
 (Gunma Astronomical Observatory) report:

 The position of GRB 091127 (Troja et al., GCN 10191) was observed
with the 150 cm telescope of Gunma Astronomical Observatory.
Starting at 13:45:44 and 14:04;55 UT on Nov.28 ( about 14.3 and
14.7 hours after the trigger), Ic and Rc frames were acquired
for sets of 5 x 3-min and  5 x 3-min exposures, respectively.

 We detected the optical counterpart (e.g., Smith et al., GCN 10192;
 Immler et al., GCN 10193) in all frames. We estimated the Rc and Ic
magnitudes relative to USNO-B1.0 R2 and I magnitudes, respectively.

mid-UT     T0+(d)    exp        mag.
-----------------------------------------------
13:54:51   0.6035    5x3min     Rc=18.37+-0.13
14:16:39   0.6187    5x3min     Ic=18.62+-0.32
-----------------------------------------------

 The R magnitude is well fitted with the fading trend from the other
observations (e.g., Xu et al. GCN 10205; Sndreev et al. GCN 10207;
Haislip et al. GCN 10219).


GRB_name: GRB091127A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10249
SUBJECT: GRB 091127: Skynet/PROMPT Observations of Possible Host Galaxy
DATE:    09/12/05 19:43:23 GMT
FROM:    Josh Haislip at U.North Carolina  <haislip@physics.unc.edu>

J. Haislip, D. Reichart, K. Ivarsen, A. LaCluyze, R. Egger, A. Foster, J.
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M.
Nysewander report:

Skynet continued to observe the afterglow (Smith et al., GCN 10192) of GRB
091127 (Troja et al., GCN 10191) with four of the 16" PROMPT telescopes at
CTIO in BVRI (Haislip et al., GCNs 10107, 10230)

Between 4.1 and 7.3 days after the trigger, the light curve is consistent
with constant emission, which suggests that we are observing the host
galaxy.

If so, we measure its brightness to be:

I = 21.19 +/- 0.14 (statistical) +/- 0.39 (systematic; calibrated to 65
USNO B1 stars).

R = 21.27 +/- 0.13 (statistical) +/- 0.37 (systematic; calibrated to 115
USNO B1 stars).

V > 21.9 (3 sigma; calibrated to 14 NOMAD stars).

B > 21.2 (3 sigma; calibrated to 65 USNO B1 stars).


GRB_name: GRB091123A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10250
SUBJECT: GRB 091123: Suzaku WAM observation of the prompt emission
DATE:    09/12/07 01:56:40 GMT
FROM:    Norisuke Ohmori at Miyazaki U  <ohmori@astro.miyazaki-u.ac.jp>

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

The very long GRB 091123 (Fermi-GBM trigger #280652919 / 091123298; 
McBreen et al., GCN 10226) was detected by the the Suzaku Wide-band 
All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV 
at 07:07:42 UT (=T0).

The observed light curve shows several pulses with a total duration of 
at least 650 s. The first bright emission episode was seen starting at 
T0-90 s, ending at T0+90 s. After the emission returned to the background 
level, three pulses was observed again at T0+220 s, T0+450 s, and T0+600 s, 
respectively.

The fluence in 100 - 1000 keV was 3.78 (-0.59, +0.45) x10^-5 erg/cm^2.
The 1-s peak flux measured from T0+45s was 2.08 (-0.31, +0.27) photons/cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0-90s to
T0+607s is fitted by a single power-law with a photon index
of 2.30 (-0.14, +0.16) (chi^2/d.o.f. = 63.4/99).

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


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

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


GRB_name: GRB091208A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10253
SUBJECT: GRB 091208: Swift detection of a burst
DATE:    09/12/08 08:56:56 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

E. A. Hoversten (PSU), P. A. Evans (U Leicester), C. Gronwall (PSU),
J. Mao (INAF-OAB), C. B. Markwardt (CRESST/GSFC/UMD),
P. T. O'Brien (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL), M. Stamatikos (OSU/NASA/GSFC) and L. Vetere (PSU)
report on behalf of the Swift Team:

At 08:46:00 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091208 (trigger=378554).  Swift could not slew to the burst
due to an Earth limb constraint.  The BAT on-board calculated location is 
RA, Dec 0.274, +65.674 which is 
   RA(J2000) = 00h 01m 06s
   Dec(J2000) = +65d 40' 25"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a FRED
structure with a duration of about 30 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

Due to an observing constraint, Swift will not slew until 
T0+49.7 minutes. There will be no XRT or UVOT data until
this time. 

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


GRB_name: GRB091208A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10254
SUBJECT: GRB 091208: ROTSE-III Optical Limits
DATE:    09/12/08 09:16:45 GMT
FROM:    Fang Yuan at ROTSE  <yuanfang@umich.edu>

F. Yuan (U Mich), W. Rujopakarn (Steward), W. Zheng (U Mich), report  
on behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB  
091208 (Swift trigger 378554; E. A. Hoversten et al, GCN 10253),  
producing images beginning 9.6 s after the GCN notice time. An  
automated response took the first image at 08:46:30.5 UT, 30.0 s after  
the burst. We took 10 5-sec and 42 20-sec exposures. These unfiltered  
images are calibrated relative to USNO A2.0 (R). Imaging is on going.

Comparison to the DSS (second epoch) reveals no new sources within the  
3-sigma Swift/BAT error circle, for both single images and coadding  
into sets of 10. Individual images have limiting magnitudes ranging  
from 14.6-16.6; we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
08:52:40.1   08:57:21.5       281     17.3          399.6       Y
08:57:30.2   09:02:12.0       281     17.4          689.7       Y


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10255
SUBJECT: GRB 091208B: BOOTES-3 optical afterglow
DATE:    09/12/08 10:11:30 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

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

"We have observed the field of GRB091208B (Swift trigger 378559)
using the 0.6m Yock-Allen robotic telescope (BOOTES-3)
located in Bleinheim, New  Zealand.  Observations began at 05:50:04 UT
(45 sec after the burst).
There is a bright optical counterpart within the XRT error
circle at coordinates (J2000 +/- 1"):

R.A.: 01:57:34.13
Dec.: +16:53:23.00

Further observations are ongoing."

[GCN OPS NOTE(11oct09): Per author's request, the time was changed
from "05:50:04" to "09:50:04".]


GRB_name: GRB091208B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10256
SUBJECT: GRB 091208B: Swift detection of a burst with an optical afterglow
DATE:    09/12/08 10:13:59 GMT
FROM:    Claudio Pagani at PSU/Swift-XRT  <pagani@astro.psu.edu>

C. Pagani (PSU), A. P. Beardmore (U Leicester),
P. A. Evans (U Leicester), C. Gronwall (PSU),
S. T. Holland (CRESST/USRA/GSFC), N. P. M. Kuin (MSSL),
C. B. Markwardt (CRESST/GSFC/UMD), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), A. Rowlinson (U Leicester),
M. Stamatikos (OSU/NASA/GSFC), G. Tagliaferri (INAF-OAB) and
L. Vetere (PSU) report on behalf of the Swift Team:

At 09:49:57 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091208B (trigger=378559).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 29.410, +16.883 which is 
   RA(J2000) = 01h 57m 39s
   Dec(J2000) = +16d 52' 57"
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 15 sec.  The peak count rate
was ~9100 counts/sec (15-350 keV), at ~8 sec after the trigger. 

The XRT began observing the field at 09:51:53.1 UT, 115.2 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 29.3920,
16.8899 which is equivalent to:
   RA(J2000)  = 01h 57m 34.09s
   Dec(J2000) = +16d 53' 23.6"
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This
location is 66 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 (4.85e+20
cm^-2, Kalberla et al. 2005), with an excess column of 3.3
(+1.52/-1.28) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 119 seconds after the BAT trigger.    There is an
afterglow in the rapidly available 2.7'x2.7' sub-image at 
   RA(J2000)  =    01:57:34.06 = 29.39193 
   DEC(J2000) =   +16:53:22.7  = 16.88963  with a 90%-confidence
error radius of about 0.6 arc sec. This position  is 0.67 arc sec. 
from the center of the XRT error circle. The estimated  magnitude is
17.9. No correction has been made for the expected extinction
corresponding to E(B-V) of 0.05.     There is a bright afterglow
candidate consistent with the XRT position. 

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


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10257
SUBJECT: GRB 091208B, RIMOTS optical upper limits  
DATE:    09/12/08 11:57:37 GMT
FROM:    Kazuhiro Noda at Miyazaki U  <kaz1206@astro.miyazaki-u.ac.jp>

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

We have observed the field covering the error circle of
GRB GRB091208B (Swift trigger 378559, GCN 10256, C. Pagani et al.)
with the unfiltered CCD camera on the 30-cm telescope
at University of Miyazaki.
The observation was started 09:59:30 UT, about 9.5 min
after the Swift trigger time.
We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog,
There is no new source at the reported position.
(GCN 10255, A. de Ugarte Postigo et al.)

the upper limits are as follows:
--------------------------------------------------------------
Start(UT) End(UT) Num. of frames Limit (mag.)
--------------------------------------------------------------
09:59:30 10:00:00 1 15.9
09:59:30 10:47:23 37 17.3
---------------------------------------------------------------


GRB_name: GRB091208B
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10258
SUBJECT: GRB 091208B: MITSuME Okayama Optical Observation
DATE:    09/12/08 12:06:40 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida@oao.nao.ac.jp>

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

We observed the field of GRB 091208B (Pagani et al., GCN 10256)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.
The observation started at 09:57:03 2009-12-08 UT, 426s after the
trigger. We detected the optical afterglow previously reported
by de Ugarte Postigo et al. (GCN 10255) and Pagani et al. (GCN
10256) in all the three bands.

The preliminary photometry results of the OT are listed below. We
used GSC2.3 catalog for flux calibration.


#PDAY    MID-UT    T-EXP       g'            Rc            Ic
------------------------------------------------------------------
0.00855  10:02:17  540.0  18.4 $B!^(B 0.2  17.6 $B!^(B 0.1  17.0 $B!^(B 0.2
0.01615  10:13:14  540.0  18.5 $B!^(B 0.2  18.1 $B!^(B 0.2  17.4 $B!^(B 0.2
------------------------------------------------------------------


GRB_name: GRB091208B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10259
SUBJECT: GRB 091208B: Enhanced Swift-XRT position
DATE:    09/12/08 12:50:30 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 466 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 091208B, 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 = 29.39223, +16.88965 which is equivalent
to:

RA (J2000): 01h 57m 34.13s
Dec (J2000): +16d 53' 22.7"

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: GRB091208B
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10260
SUBJECT: GRB 091208B:  MITSuME Akeno Optical Observation
DATE:    09/12/08 13:34:54 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

H. Nakajima, Y. Yatsu, Y.A. Mori, A. Endo, T. Shimokawabe, and
N. Kawai (Tokyo Tech)  report on behalf of the MITSuME collaboration:

We observed the field of GRB 091208B (Pagani et al., GCN 10256)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope at Akeno, Japan.
The observation started at 2009-12-08 09:50:45 UT, 48s after the
trigger.  We detected the optical afterglow (de Ugarte Postigo et al.
GCN 10255, Pagani et al. GCN 10256, Yoshida et al. GCN 10258)
in all the three bands.

The preliminary photometry results of the OT are listed below. We
used GSC2.3 catalog for flux calibration.

 MID-UT    T-EXP    g'         Rc            Ic
------------------------------------------------------------------
 09:51:15  60.0   17.2 $B!^(B 0.2  16.1 $B!^(B 0.1  15.5 $B!^(B 0.1
------------------------------------------------------------------


GRB_name: GRB091208A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10261
SUBJECT: GRB 091208A, RIMOTS optical upper limits
DATE:    09/12/08 13:40:03 GMT
FROM:    Kazuhiro Noda at Miyazaki U  <kaz1206@astro.miyazaki-u.ac.jp>

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

We have observed the field covering the error circle of
GRB GRB091208A (Swift trigger 378554, GCN 10253, Hoversten et al.)
with the unfiltered CCD camera on the 30-cm telescope
at University of Miyazaki.
The observation was started 09:04:56 UT, about 19 min
after the Swift trigger time.
We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog,
There is no new source at the reported position.

the upper limits are as follows:
--------------------------------------------------------------
Start(UT) End(UT) Num. of frames Limit (mag.)
--------------------------------------------------------------
09:04:56 09:05:26  1 15.8
09:04:56 09:48:39 33 17.3 
---------------------------------------------------------------


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10262
SUBJECT: GRB 091208B: Faulkes Telescope North and South Optical Afterglow
DATE:    09/12/08 13:52:33 GMT
FROM:    Zach Cano at ARI/John Moores Liverpool  <zec@astro.livjm.ac.uk>

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

The 2-m Faulkes Telescopes North and South robotically followed up 
GRB091208B (SWIFT trigger 378559; Pagani et al. GCN 10256) beginning 1.78
min after the GRB trigger time.  We detect the optical afterglow in BRi'
filters at the location reported by de Ugarte Postigo et al. (GCN 10255)
and Pagani et al. (GCN 10256).

We derive the following preliminary magnitudes wrt USNOB1:

Filter    Mag     Merr      T-To (s)
-------------------------------------------
  R      17.75    0.02      572
  R      18.48    0.03     1656
  I      17.51    0.05     1036
  I      18.34    0.04     3749

From our observations we derive a power-law decay constant of ~ 0.6 for
both filters.

We have not corrected our magnitudes for the small amount of foreground
reddening along the line of sight (E(B-V) = 0.05, corresponding to Av =
0.17 (Schlegel et al. 1998)).

Observations and analysis are ongoing.

This message may be cited.


GRB_name: GRB091208B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10263
SUBJECT: GRB 091208B: Gemini-North redshift
DATE:    09/12/08 15:09:46 GMT
FROM:    Klaas Wiersema at U of Leicester  <kw113@star.le.ac.uk>

K. Wiersema, N. R. Tanvir (U. Leicester), A. Cucchiara (PSU),
A. J. Levan (U. Warwick) & D. Fox (PSU) report:

We observed the afterglow of GRB 091208B (Pagani et al. GCN 10256;
de Ugarte Postigo et al. GCN 10255) with the GMOS-N spectrograph on Gemini
North, beginning at 11:17 UT on December 8. We use the R400 grism.
The resulting spectrum covers the wavelength range 4000-8400 A and shows 
clear absorption lines of the MgII doublet (2796,2803), MgI (2853), FeI 
(2967), FeII (2586,2600) and MnII (2576,2594,2606) at a common redshift
of z = 1.063.

We thank the Gemini-N staff, in particular K. Chiboucas, for
performing this observation.


GRB_name: GRB091208A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10264
SUBJECT: GRB 091208A Swift-BAT refined analysis
DATE:    09/12/08 15:58:56 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

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

Using the data set from T-61 to T+242 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 091208A (trigger 
#378554) (Hoversten, et al., GCN Circ. 10253).  The BAT ground-
calculated position is RA, Dec = 0.295, 65.680 deg which is
    RA(J2000)  =  00h 01m 10.9s
    Dec(J2000) = +65d 40' 47.7"
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 88%.

The mask-weighted light curve shows a single FRED with some additional
structure on the decaying side. The tail appears to be quite long at
low energy, with emission detectable for up to 200 seconds after the 
trigger. T90 (15-350 keV) is 29.1 +- 2.5 sec (estimated error including 
systematics).

The time-averaged spectrum from T-0.3 to T+32.8 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
0.81 +- 0.10.  The fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-06
erg/cm2.  The 1-sec peak photon flux measured from T+0.15 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 results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/378554/BA/


GRB_name: GRB091208B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10265
SUBJECT: GRB 091208B, Swift-BAT refined analysis
DATE:    09/12/08 15:59:30 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 (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),
D. M. Palmer (LANL), C. Pagani (PSU), A. M. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-60 to T+243 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 091208B (trigger 
#378559) (Pagani, et al., GCN Circ. 10256).  The BAT ground-
calculated position is RA, Dec = 29.411, 16.881 deg which is
    RA(J2000)  =  01h 57m 38.5s
    Dec(J2000) = +16d 52' 50.7"
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 10%.

The mask-weighted light curve shows two separated FRED peaks. The first
at T0 was weaker and softer than the second at T+8 sec.
T90 (15-350 keV) is 14.9 +- 3.7 sec (estimated error including
systematics).

The time-averaged spectrum from T-0.2 to T+22.3 sec is best fit by a
simple power-law model.  The power law index of the time-averaged
spectrum is 1.74 +- 0.11.  The fluence in the 15-150 keV band was
3.3 +- 0.2 x 10^-06 erg/cm2.  The 1-sec peak photon flux measured from
T+8.1 sec in the 15-150 keV band was 15.2 +- 1.0 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/378559/BA/


GRB_name: GRB091208B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10266
SUBJECT: GRB 091208B: Fermi GBM observation
DATE:    09/12/08 17:42:47 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

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

"At 09:49:57.96 UT on 08 December 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091208B (trigger 281958599 / 091208410)
which was also detected by the Swift-BAT (Pagani et al. 2009, GCN 10256).
The GBM on-ground location is consistent with the Swift position.
This burst was also independently detected by INTEGRAL SPI-ACS.

The angle from the Fermi LAT boresight is 56 degrees.
Moreover, this burst was bright enough to result in
a Fermi spacecraft repointing maneuver.

The GBM light curve consists of two pulses
with a duration (T90) of about 15 s (8-1000 keV).
The time-averaged spectrum from T0-0.128 s to T0+14.592 s is
well fit by a power law function with an exponential
high energy cutoff.  The power law index is -1.48 (+0.05/-0.05) and
the cutoff energy, parameterized as Epeak, is 144.20 (+18.00/-13.90) keV
(CSTAT 829 for 604 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(5.8 +/- 0.2)E-06 erg/cm^2. The 0.128 sec peak photon flux measured
starting from T0+8.45 s in the 8-1000 keV band is 32.4 +/- 1.1 ph/s/cm^2.

A Band function fits the spectrum equally well (CSTAT 827 for 603 d.o.f.)
with Epeak= 124.00 (+20.10/-19.40) keV, alpha = -1.44 (+0.07/-0.06)
and beta = -2.32 (+0.19/-0.47).

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


GRB_name: GRB091208B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10267
SUBJECT: GRB091208B: Swift/UVOT refined analysis
DATE:    09/12/08 18:00:07 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

  M. De Pasquale (MSSL/UCL) and  C. Pagani (PSU)  report on
behalf of the Swift UVOT team.

  The Swift UltraViolet/Optical Telescope (UVOT) began settled
observations of the GRB 091208B (Swift BAT trigger number 378559;
Pagani et al. GCN Circ. 10256) 119 s after the BAT trigger
with an exposure in the UVOT white filter.

  A new optical source is found at position
RA, Dec = 29.39204, 16.88967, corresponding to

  RA  (J2000) =  01 57 34.09
  Dec (J2000) = +16 53 22.82

This is within 0.6 arseconds from the XRT enhanced position
(Osborne et al., GCN Circ. 10259) and consistent with it.
  The detection is in all 3 filters UVOT used at early epoch.

  The initial magnitudes are given below.

Filter  Time(s)       Mag      Err

wh      119-269      17.92    0.04

b       588-605      18.38    0.29

u       333-583      18.63    0.09

  We caution that data analysis is slightly complicated by the
presence of a dim source 3 arcsecond away from the afterglow.

  The values quoted above are on the UVOT Photometric System
(Poole et al., 2008, MNRAS 383,627). They are not corrected for
the expected Galactic extinction, corresponding to a reddening
of E(B-V)=0.05.


GRB_name: GRB091208B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10268
SUBJECT: GRB 091208B: Swift-XRT refined analysis
DATE:    09/12/08 20:50:26 GMT
FROM:    Claudio Pagani at PSU/Swift-XRT  <pagani@astro.psu.edu>

C. Pagani (PSU) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

We have analysed 3.6 ks of XRT data for GRB 091208B (Pagani et al. GCN
Circ. 10256), from 132 s to 12.2 ks after the BAT trigger. The data are
entirely in Photon Counting (PC) mode. The enhanced XRT position for this
burst was given by Osborne et al. (GCN. Circ 10259).

The light curve presents bumps and mini-flares and can be modelled with a
power-law decay with a decay index of alpha=0.73 (+0.04, -0.05).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.32 (+0.18, -0.16). The
best-fitting absorption column is 2.9 (+/-0.5) x 10^21 cm^-2, in excess of
the Galactic value of 4.8 x 10^20 cm^-2 (Kalberla et al. 2005). The counts
to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from
this spectrum is 3.7 x 10^-11 (7.2 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index of 0.73,
the count rate at T+24 hours will be 0.034 count s^-1, corresponding to an
observed (unabsorbed) 0.3-10 keV flux of 1.3 x 10^-12 (2.5 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/00378559.

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


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10269
SUBJECT: GRB091208B: NOT optical observations
DATE:    09/12/08 22:10:36 GMT
FROM:    Dong Xu at DARK,NBI  <dong@astro.ku.dk>

D. Xu (WIS, DARK/NBI), G. Leloudas, D. Malesani (DARK/NBI), P. Jakobsson
(Univ. of Iceland), J. Lindberg, J. Andersen (NOT) report on behalf of a 
larger collaboration:

We observed the field of GRB091208B (Pagani et al. GCN 10256; de Ugarte 
Postigo et al. GCN 10255) at the Nordic Optical Telescope equipped with 
ALFOSC. The 2x300s frames were obtained starting at 20:46:43 UT on Dec. 
08th, 10.9878 hr after the burst trigger.

The magnitude of the afterglow is R~20.9 with respect to stars in the 
USNO B1 catalog. Comparison with the measurement in Cano et al. (GCN 
10262) indicates a general decay slope of ~0.6-~0.7 in the R band.

[GCN OPS NOTE(22dec09): Per author's request, the date in the 2nd sentence
was changed ""from Nov 28" to "Dec 8".]


GRB_name: GRB091208A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10270
SUBJECT: GRB 091208A: Swift-XRT observations
DATE:    09/12/08 22:24:53 GMT
FROM:    Claudio Pagani at PSU/Swift-XRT  <pagani@astro.psu.edu>

C. Pagani, L. Vetere (PSU), P.A. Evans (U. Leicester), J. L. Racusin
(NASA/GSFC) and E. A. Hoversten (PSU) report on behalf of the Swift Team:

Swift/XRT observed the field of GRB 091208A (BAT trigger number 378554;
Hoversten et al. GCN Circ. 10253) from 3.1 ks to 3.3 ks after the BAT
trigger and again from 25 ks to 27 ks after the BAT trigger.  The first
observation was delayed due to an observing constraint.

During the first observation no X-ray afterglow is detected inside the BAT
error circle (Barthelmy et al. GCN Circ. 10264) in 180 seconds of Photon
Counting data.  The corresponding 3-sigma upper limit is 0.04 counts/s. 
For comparison, the median XRT count rate for long GRB afterglows at 3 ks
after the BAT trigger is approximately 0.1 counts/s.

During the second observation no X-ray afterglow is detected inside the BAT
error circle in 694 seconds of PC data.  The corresponding 3-sigma upper
limit is 0.01 counts/s.  For comparison, the median XRT count rate for long
GRB afterglows at 25 ks after the BAT trigger is approximately 0.02
counts/s.  Based on the count rates of the XRT afterglows observed during
the Swift mission the chance of detecting a long GRB with the XRT in a 1 ks
observation 25 ks after the BAT trigger is 61%.

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


GRB_name: GRB091208B
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10271
SUBJECT: GRB 091208B: GROND observations
DATE:    09/12/09 05:13:59 GMT
FROM:    Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>

Adria Updike (Clemson University), Andrea Rossi (Tautenburg Obs.) and
Jochen Greiner (MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 091208B (Swift trigger 378559, Pagani et al.,
GCN #10256) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla
Observatory (Chile).

First observations started at 01:07 UT on Dec 09, 15h17m after the GRB 
trigger,
for a total integration time of 7.7 min in g'r'i'z' and 8min in JHK.

For the afterglow reported by Pagani et al. and
de Ugarte Postigo et al. (GCN #10255) we estimate the
following preliminary magnitudes (in the AB system):

g' = 22.64  +- 0.15
r' = 21.88  +- 0.14
i' = 21.65  +- 0.17
z' = 21.35  +- 0.17
J  = 20.61  +- 0.10
H  = 20.5   +- 0.3
K analysis on going

These magnitudes are in agreement with a afterglow at redshift z<3.5.
After correction for the different filter and magnitude system,
a comparison with other observation (Xu et al.,GCN #10269 and Cano et
al., GCN #10262) confirms that the afterglow is decaying with the slope
of 0.6-0.7 reported by Xu et al. .

Given magnitudes are calibrated against GROND zeropoints as well as 2MASS
field stars. The errors take in account zero point uncertainties. 
Magnitudes are not corrected for the expected Galactic foreground
extinction corresponding to a reddening of E_(B-V)=0.05 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB091208B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10272
SUBJECT: GRB 091208B: Keck HIRES redshift confirmation
DATE:    09/12/09 06:11:31 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley (UC Berkeley), J. X. Prochaska (UCSC), P. Kalas, A. Howard, 
M. Fitzgerald, G. Marcy, and J. Graham (UCB) report:

Starting at 10:58:17 UT on December 8 we initiated a single 1200 second 
exposure of the afterglow of GRB 091208B (GCN 12055, de Ugarte Postigo 
et al.; GCN 10256, Pagani et al.) with HIRES-r on the 10m Keck I 
telescope.  Consistent with the result of Wiersema et al. (GCN 10263), 
we detect absorption lines from MgII and MnII at a redshift of 
z=1.0633+/-0.0003.  Additionally, we detect fine-structure transitions 
of FeII confirming that this is the redshift of the GRB.


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10273
SUBJECT: GRB 091208B: optical observations
DATE:    09/12/09 12:32:39 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

M.Andreev,  A.Sergeev, N.Parakhin, N.Karpov (Terskol Branch of  Institute of 
Astronomy), Yu. Kuznietsova (Main Astronomical Observatory NASU), V.Petkov 
(Baksan Neutrino Observatory INR) and A. Pozanenko (IKI) on behalf of larger 
GRB follow up collaboration report:

We observed the field of the Swift GRB 091208B (Pagani  et al. GCN  10256) 
with the Z-600 telescope of Mt.Terskol observatory in R-filter  on  Dec. 08 
starting at (UT) 15:40. In combined images we  detect the optical afterglow 
(Ugarte Postigo et al. GCN 10255, Pagani  et al. GCN  10256).

Preliminary photometry is based on the USNO-B1.0 reference star 
#1069-0020318  assuming  R2=17.47:

UT     Filter, Exposure, mag.  err.
(mid)             (s)

16:10  R  30x120  20.15  0.25
18:11  R  30x120  20.60  0.25
19:11  R  30x120  20.9    0.3
20:19  R  30x120  21.0    0.3

Combined image can be found in
http://grb.rssi.ru/GRB091208B/GRB091208B_Terskol600_R.jpg 


GRB_name: GRB091208A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10274
SUBJECT: GRB091208A: Swift/UVOT refined analysis
DATE:    09/12/09 13:43:27 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

  M. De Pasquale (MSSL/UCL) and E. Hoversten (PSU) report on the behalf of 
the Swift team:

Swift/UVOT observed the field of GRB091208A from 4.32 ks to 4.33 ks after 
the BAT trigger in the v filter and then from 26.01 to 26.71 ks after the 
trigger in u, v and white filters. No new source is detected in the BAT 
error circle  (Barthelmy et al., GCN Circ. 10264). We caution though that 
a small fraction of BAT error circle is not covered by UVOT exposures.
3 sigma upper limits on magnitudes are as follows:

Filter T_start(s)  T_stop(s)      Exp(s)     Mag
v          4318       4328           10     >17.4
v         26513      26717          200     >19.4
wh        26261      26507          243     >21.1
u         26008      26255          243     >20.1

The values quoted above are on the UVOT Photometric System
(Poole et al., 2008, MNRAS 383,627). They are not corrected for
the expected strong Galactic extinction, corresponding to a reddening
of E(B-V)=1.6.


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10275
SUBJECT: GRB 091208B: GAO 150cm telescope Optical Observation
DATE:    09/12/10 08:51:42 GMT
FROM:    Kenzo Kinugasa at Gunma Astro. Obs/Japan  <kinugasa@astron.pref.gunma.jp>

K. Kinugasa, S. Honda, H. Takahashi, H. Taguchi, O. Hashimoto
 (Gunma Astronomical Observatory) report:

 The position of GRB 091208B (Pagani et al., GCN 10256) was observed
with the 150 cm telescope of Gunma Astronomical Observatory.
Starting at 10:21:09 UT on Dec.8 ( 0.52 hours after the trigger),
both Rc and Ic frames were acquired for sets of 3 x 2-min and
5 x 5-min exposures.

 We detected the optical counterpart (e.g., de Ugarte Postigo et al.,
GCN 10255; Yoshida et al. GCN 10258) in all frames. We estimated the
Rc and Ic magnitudes relative to USNO-B1.0 R2 and I magnitudes,
respectively.

mid-UT     T0+(d)     exp                mag.
-----------------------------------------------------
10:50:45   0.01796    3x2min, 5x3min     Rc=18.8+-0.1
11:07:20   0.02273    3x2min, 5x3min     Ic=18.4+-0.1
-----------------------------------------------------

 The R magnitude is consistent with the fading trend of a power-law
slope of ~0.7 from the other optical observations (e.g. Cano et al.
 GCN 10262; Xu et al. GCN 10269; Nakajima et al. GCN 10260).


GRB_name: GRB091208A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10276
SUBJECT: Konus-Wind observation of GRB 091208A
DATE:    09/12/10 16:47:11 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 091208A (Swift-BAT trigger #378554:
Hoversten et al., GCN 10253; Barthelmy et al., GCN 10264)
triggered Konus-Wind at T0=31563.038s UT (08:46:03.038).

The burst light curve shows a smooth single-pulse structure
with a total duration of ~30 s. The Konus-Wind light
curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB091208_T31563/

As observed by Konus-Wind the burst
had a fluence of 6.2(+/-1.0)x10-6 erg/cm2,
and a 256-ms peak flux measured from T0-0.256s
of 1.3(+/-0.2)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+24.832 s) can be fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), with
alpha = +0.24(-0.5, +0.7),
and Ep = 314(-50, +70) keV (chi2 = 74/61 dof).

The spectrum of the most intense part of the burst
(measured from T0 to T0+8.448 s) is well fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = +0.13(-0.4, +0.55),
and Ep = 316(-44, +60) keV (chi2 = 47/61 dof).

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


GRB_name: GRB091208A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10277
SUBJECT: GRB 091208A: GAO 150cm telescope Optical Observation
DATE:    09/12/11 11:19:27 GMT
FROM:    Kenzo Kinugasa at Gunma Astro. Obs/Japan  <kinugasa@astron.pref.gunma.jp>

K. Kinugasa, S. Honda, H. Takahashi, H. Taguchi, O. Hashimoto
 (Gunma Astronomical Observatory) report:

 The field of GRB 091208A (Hoversten et al. GCN 10253) was observed
with the 150 cm telescope of Gunma Astronomical Observatory. Starting
at 09:09:06 UT on Dec.8 ( 23.1 min after the trigger), both Rc and Ic
frames were acquired for sets of 5 x 0.5-min and  3 x 2-min exposures.

The limiting magnitude in combined image is estimated as Rc~20.5 and
Ic~20.0. We did not detect any new point source within the BAT error
circle down to the magnitudes of R~20.2 and I~19.5 relative to
USNO-B1.0 R2 and I magnitudes, respectively.


GRB_name: GRB091208A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10278
SUBJECT: GRB 091208A: Suzaku WAM observation of the prompt emission
DATE:    09/12/12 04:00:04 GMT
FROM:    Yusuke Nishioka at Miyazaki U.  <yusuke613@astro.miyazaki-u.ac.jp>

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

  The long GRB 091208A (Swift/BAT trigger #378554 ; Barthelmy et al., 
 GCN 10264) triggered the Suzaku Wide-band  All-sky Monitor (WAM) which 
 covers an energy range of 50 keV - 5 MeV at 2009-12-08 08:46:00.546 UT (=T0).

 The observed light curve shows a single peak starting at T0 s, 
 ending at T0+10 s with a duration (T90) of about 6.6 seconds. 
 The fluence in 100 - 1000 keV was 4.85(-0.99, +0.65) x10^-6 erg/cm^2. 
 The 1-s peak flux measured from T0 s was 1.94 (-0.60, +0.61) 
 photons/cm^2/s in the same energy range.

 Preliminary result shows that the time-averaged spectrum from T0-0.5 s to 
 T0+10 s is well fitted by a single power-law with a photon index of 
 2.04 (-0.24, +0.28) (chi^2/d.o.f = 48.5/33).

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

 The light curves for this burst are available at:

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


GRB_name: GRB091208B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10279
SUBJECT: GRB 091208B: Xinglong TNT optical observation
DATE:    09/12/13 08:53:10 GMT
FROM:    L.P. Xin at NAOC  <xlp@bao.ac.cn>

L.P. Xin, S. B, Qian,  Y.L. Qiu,  J. Wang, 
J.Y. Wei, W. K. Zheng, J. S. Deng, and J. Y. Hu 
on behalf of EAFON report:

We observed the optical afterglow of GRB 091208B
(Pagani et al. GCN 10256) with Xinglong TNT telescope 
from Nov. 8th,  10:12:31.6(UT), 23 min after the burst. 
The optical counterpart was clearly detected in our images.
The brightness was estimated to be about R~18.5 relative to
the USNO-B1.0 R2 mag, at the meam time of 30 min 
after the burst.

This message may be cited.  

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


GRB_name: GRB091215A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10281
SUBJECT: GRB 091215: Faulkes Telescope North observations
DATE:    09/12/15 17:21:32 GMT
FROM:    Andrea Melandri at Liverpool John Moores U  <axm@astro.livjm.ac.uk>

A. Melandri (Liverpool JMU), C. Guidorzi (U. Ferrara), C.G. Mundell,
Z. Cano (Liverpool JMU), A. Gomboc (U. Ljubljana), N. Tanvir (Leicester)
report on behalf of a large collaboration:

On December 15th at 15:43:50 UT we observed the field of the possible
GRB 091215 (trigger 379449, Sakamaoto et al., GCN 10280) with the the
2-m Faulkes Telescope North. Automatic observations were performed
using BVRi' filters.

We do not detect any obvious bright optical afterglow in the field of  
view, that
covers almost entirely the BAT error circle reported by Sakamoto et  
al. (GCN 10280).

We calibrated our images using SDSS for the i' band and USNOB-1 for the
R band and derived conservative upper limits for the OT :

Mid Time   Total Exp      Filter    Magnitude
(min)                  (s)
-----------------------------------------------------------
  5.3                    30              R          > 18.5
16.5                 100              i'          > 19.2
-----------------------------------------------------------


GRB_name: GRB091221A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10283
SUBJECT: GRB 091221: Swift detection of a burst
DATE:    09/12/21 21:17:35 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

H. A. Krimm (CRESST/GSFC/USRA), D. N. Burrows (PSU),
P.A. Curran (MSSL-UCL), A. de Ugarte Postigo (INAF-OAB),
N. Gehrels (NASA/GSFC), D. Grupe (PSU), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
N. P. M. Kuin (MSSL), J. Mao (INAF-OAB),
R. Margutti (Univ Bicocca&OAB), C. B. Markwardt (CRESST/GSFC/UMD),
F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),
D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC),
P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-IASFPA),
M. H. Siegel (PSU), M. C. Stroh (PSU), E. Troja (NASA/GSFC/ORAU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 20:52:52 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 091221 (trigger=380311).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 55.754, +23.212 which is 
   RA(J2000) = 03h 43m 01s
   Dec(J2000) = +23d 12' 42"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a peak from T+0 to T+15
seconds with a second, larger peak from T+15 to T+40. There is
some complexity in the light curve from A0535+262 (currently in outburst
at ~5 Crabs of flux) in the Field Of View, but the GRB peaks are
distinguishable from the softer A0535+262 emission.  The peak count
rate was 3500 counts/sec at ~30 sec after the trigger. 

The XRT began observing the field at 20:54:04.7 UT, 72.4 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 55.79831, 23.24030
which is equivalent to:
   RA(J2000)  = 03h 43m 11.59s
   Dec(J2000) = +23d 14' 25.1"
with an uncertainty of 4.2 arcseconds (radius, 90% containment). This
position may be improved as more data are received; the latest position
is available at http://www.swift.ac.uk/sper.  This position is 
170 arcseconds from the BAT position. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.09e+21 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 1.47e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 79 seconds after the BAT trigger. No credible
afterglow candidate has  been found in the initial data products. The
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  0.22.  We note the possibility of a faint source on the
northern edge of the XRT error circle.  Further analysis is
forthcoming. 

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


GRB_name: GRB091221A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10284
SUBJECT: GRB 091221: ROTSE-III Detection of Optical Counterpart
DATE:    09/12/21 21:37:02 GMT
FROM:    Shashi Bhushan Pandey at ROTSE  <shaship@umich.edu>

GRB 091221: ROTSE-III Detection of Optical Counterpart

W. Zheng, F. Yuan and S. B. Pandey (U Mich), report on behalf of the ROTSE
collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,
responded to GRB 091221 (Swift trigger 380311, GCN 10283 Krimm et al.). The
first image was at 20:53:18.1 UT, 25.8 s after the burst (9.1 s after the
GCN notice time). The unfiltered images are calibrated relative to USNO
A2.0. We detect a 17.4 magnitude, source with coordinates:

     03:43:11.47      +23:14:29.38    (J2000), with positional uncertainty
of 1" or better

start UT     mag     mlim(of image)
----------------------------------
20:54:49.5     17.4     18.0 


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

A jpeg image is available at
http://www.rotse.net/images/gsb380311_3c011-020_key.jpg, the candidate is
marked as 110.

Continuing observations are in progress. 


GRB_name: GRB091221A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10285
SUBJECT: GRB 091221: UVOT Confirmation of an Optical Afterglow
DATE:    09/12/21 22:12:23 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <Stephen.T.Holland@nasa.gov>

S. T. Holland (CRESST/GSFC/USRA), M. de Pasquale (MSSL),
P. Kuin (MSSL), and H. A. Krimm (CRESST/GSFC/USRA)
report on the behalf of the Swift/UVOT team:

       The Swift/UVOT observed the field of GRB 091221 (Krimm et
al. 2009, GCN Circ. 10283) starting approximately 80 s after the BAT
detection.  We confirm the optical afterglow detected by Krimm et
al. 2009, GCN Circ 10283 and Zheng et al. 2009, GCN Circ. 10284.  The
preliminary UVOT position is

     RA =  03:43:11.47 =  55.79771 deg
    Dec = +23:14:28.9  = +23.24136 deg

with a preliminary error estimate of 0.6 arcsec (radius, 90%
containment).  The preliminary white magnitude is

Filter     TSTART     TSTOP     EXPOSURE        Mag   Err
---------------------------------------------------------
White          80       230          150      20.22  0.28
---------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight corresponding to a
reddening of E_{B-V} = 0.22 mag (Schlegel et al., 1998, ApJS, 500,
525).  All photometry is on the UVOT photometry system described in
Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB091221A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10286
SUBJECT: GRB 091221, GROND observations
DATE:    09/12/22 03:20:01 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

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

GROND (Greiner et al. 2008, PASP 120, 405), the 7-channel imager mounted 
at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile), started 
follow-up observations of GRB 091221 (Krimm et al. 2009, GCN 10283) on Dec 
22, at 01:27 UT (4.5 hrs after the burst).

For the suggested GRB afterglow (Zheng et al. 2009, GCN 10284; Holland et 
al. 2009, GCN 10285), based on a first 8 min exposure, we estimate the 
following preliminary magnitudes (in the AB system):

g' = 22.90 +/- 0.30
r' = 22.27 +/- 0.30
i' = 21.95 +/- 0.30
z' = 22.20 +/- 0.30
J  = 20.16 +/- 0.20
H  > 19.9
K  > 19.1

using GROND zeropoints and 2MASS catalog (airmass 1.8). Observations are 
ongoing.

Taking into account a Galactic reddening of E(B-V)=0.22 mag (Holland et 
al. 2009, GCN 10285), we estimate a photometric redshift of z<3.5. At 
present we cannot decide if the z'-band magnitude is indicating to a 
broad-band absorption feature or if we underestimate the magnitude error
in this band (where the source is very faint).


GRB_name: GRB091221A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10287
SUBJECT: GRB 091221: Enhanced Swift-XRT position
DATE:    09/12/22 09:17:25 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 3.7 ks of XRT Photon Counting mode data and 7 UVOT
images, we find an astrometrically corrected X-ray position (using the
XRT-UVOT alignment and matching UVOT field sources to the USNO-B1
catalogue): RA, Dec =
55.79749, 23.24119 which is equivalent to:

RA (J2000):  03 43 11.40
Dec (J2000): +23 14 28.3

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

This position may be improved as more data are received.  The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB091221A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10288
SUBJECT: GRB 091221: Swift-XRT refined analysis
DATE:    09/12/22 10:50:17 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao (INAF-OAB) and H. A. Krimm (CRESST/GSFC/USRA) report on behalf of 
the Swift-XRT team:

We have analysed 4.7 ks of XRT data for GRB 091221 (Krimm et al. GCN 
Circ. 10283), from 78 s to
11.6 ks after the BAT trigger. The data comprise 332 s in Windowed 
Timing (WT) mode with the remainder
 in Photon Counting (PC) mode. The UVOT-enhanced XRT position was given 
in Evans et al.
(GCN Circ. 10287).

The light curve shows a flare feature from T0+90 s to T0+200 s, the peak 
value is about 55 count/s at
T0+106 s. After that, the light curve can be modelled with a power-law 
decay with a decay index of
alpha=1.07  0.05.

A spectrum formed from the WT mode data can be fitted with an absorbed 
power-law with a photon spectral
 index of 2.52 (+0.16, -0.17). The best-fitting absorption column is 3.6 
(+/- 0.4) x 1021 cm^-2, in excess of
 the Galactic value of 1.1 x 1021 cm^-2 (Kalberla et al. 2005). 
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor 
deduced from this spectrum is
4.4 x 10^-11 (7.2 x 10^-11) erg cm^-2 count^-1. The spectrum formed from 
the PC mode data can be fitted
with an absorbed power-law with a photon spectral index of 1.68 (+0.45, 
-0.51). The best-fitting absorption
column is about 1.1 x 1021 cm^-2, in consistent with the Galactic value.

If the light curve continues to decay with a power-law decay index of 
1.07, the count rate at T0+24 hours
will be 2.3 x 10^-3 count s^-1, corresponding to an observed 
(unabsorbed) 0.3-10 keV flux of
1.4 x 10^-13 (1.6 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at 
http://www.swift.ac.uk/xrt_products/00380311.

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


GRB_name: GRB091221A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10289
SUBJECT: GRB 091221: Swift/UVOT refined analysis
DATE:    09/12/22 13:58:52 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

   M. De Pasquale (MSSL/UCL) and H. Krimm (CRESST/GSFC/USRA)
report on behalf of the Swift/UVOT team:

  The Swift/UVOT began settled observations of the field of GRB091221
80s after the BAT trigger with a 150s finding chart exposure in
the White filter.

  We detect the optical afterglow in the finding chart exposure.
The refined UVOT position is RA = 55.79750, Dec = 23.24119 (J2000), 
corresponding to

             RA = 03h 43m 11.40s,
             Dec = +23d 14m 28.3s (J2000)

with an estimated uncertainty of 0.6 arcsec (radius, 90% confidence).
This position is consistent with the XRT enhanced position (Evans
et al., GCN 10287) and ground-based detections (Zheng et al., GCN
10284; Klose et al., GCN 10286).

  The afterglow is not detected anymore in single or summed exposures
in all filters. Preliminary magnitudes and 3 sigma upper limits
are reported below.

Filter    T_start(s) T_stop(s)  Exposure(s)    Mag  Err
-----------------------------------------------------------------------
white        80        230       149.8       20.19 +/- 0.27
white      3657      11605       927.1          >21.62
v          4068       5704       393.2          >19.56
b          3452      11054      1278.4          >21.11
u          4683      10142      1083.4          >20.68
uvw1       4478       6075       354.4          >19.96
uvm2       4273       5909       393.3          >19.79
uvw2       3863       5499       393.3          >20.07
------------------------------------------------------------------------

The values quoted above are not corrected for the heavy Galactic 
extinction corresponding to the reddening of E(B-V) = 0.22 in the 
direction of the burst (Schlegel et al. 1998, ApJS, 500, 525). The 
photometry is on the UVOT photometric system described in Poole et al. 
(2008, MNRAS, 383, 627).

[GCN OPS NOTE(22dec09): Per author's request, the Subject-line
was changed from 091208B to 091221.]


GRB_name: GRB091221A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10290
SUBJECT: GRB091221: Swift/UVOT refined analysis, correction.
DATE:    09/12/22 14:06:10 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

  M. De Pasquale (MSSL/UCL) reports:

  GCN circular 10289 title is wrong. It should be

  GRB091221: Swift/UVOT refined analysis

  not GRB091208B.

  I apologize for any confusion.


GRB_name: GRB091221A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10291
SUBJECT: GRB 091221 Swift-BAT refined analysis
DATE:    09/12/22 16:44:09 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

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

Using the data set from T-240 to T+962 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 091221 (trigger #380311)
(Krimm, et al., GCN Circ.#10283).  The BAT ground-calculated position is
RA, Dec = 55.798, 23.243 deg which is
    RA(J2000)  =  03h 43m 11.6s
    Dec(J2000) = +23d 14' 35.2"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 62%.

The mask-weighted light curve shows a weak peak from T-45 to T-20 sec 
and a stronger, slow-rise, complex peak from T-10 to T+42 sec.  T90
(15-350 keV) is 68.5 +- 5.5 sec (estimated error including systematics).

The time-averaged spectrum from T-43.6 to T+41.1 sec is best fit by a 
simple power-law model.  The power law index of the time-averaged
spectrum is 1.59 +- 0.06.  The fluence in the 15-150 keV band is
5.7 +- 0.2 x 10^-06 erg/cm2.  The 1-sec peak photon flux measured from
T+20.70 sec in the 15-150 keV band is 3.0 +- 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/380311/BA/


GRB_name: GRB091117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10292
SUBJECT: GRB 091117: Swift-XRT late time observations
DATE:    09/12/23 16:17:58 GMT
FROM:    Valerio D'Elia at INAF-OAR  <delia@mporzio.astro.it>

V. D'Elia, G. Stratta, M. Perri (ASDC), J. Cummings (GSFC/CRESST) report
on behalf of the Swift-XRT team:

Swift-XRT has observed the field of GRB 091117 about one month after  
the burst
(Cummings et al. GCN Circ. 10171).   The data set consists of two  
further
observations, 9.7 ks and 9.2 ks, from 32.8 to 34.2 days after the  
trigger.
The data are entirely in Photon Counting (PC) mode.

We found that Source #1 (Berger, GCN Circ. 10173; D'Elia et al.,
GCN Circ. 10177; Fox, GCN Circ. 10179, D'Elia et al., GCN Circ 10181)
is still detected with a count rate of (2.95+/-0.70)e-3 cts/s (first
observation) and (3.42+/-0.75)e-3 cts/s (second observation),
thus showing no evidence of fading with respect to the first Swift
follow-up observations.  Thus evidence of possible fading of Source #1,
reported in Fox (GCN Circ. 10179), D'Elia et al. (GCN Circ.10181) and
Fox & Berger (GCN Circ. 10232), is not confirmed by these measurements.

Source #2 (D'Elia et al., GCN Circ. 10177; Fox, GCN Circ. 10179,  
D'Elia et al.,
GCN Circ 10181) is also detected, and the derived count rate is
(2.03+/-0.55)e-3 cts/s (first observation) and (1.85+/-0.54)e-3 cts/s
(second observation).  No evidence of a fading behavior is found for  
this
source either.

All quoted errors are given at the 1-sigma level.

In view of these XRT observations, we can safely conclude that neither
source is the X-ray afterglow of GRB091117.

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


GRB_name: GRB091221A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10293
SUBJECT: GRB 091221: Fermi GBM Observation
DATE:    09/12/23 21:02:35 GMT
FROM:    Colleen A. Wilson at NASA/MSFC/NSSTC  <colleen.wilson@nasa.gov>

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

"At 20:52:57.22 UT on 21 December 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 091221 (trigger 283121579 / 091221870) which 
also triggered the SWIFT-BAT (Krimm et al. 2009, GCN 10283) The GBM 
on-ground location is consistent with the Swift position.
 
The angle from the Fermi LAT boresight is 53 degrees.

The GBM light curve shows/consists of single structured peak with a 
duration (T90) of about 32 s (8-1000 keV). The time-averaged spectrum 
from T0-2 s to T0+30 s is adequately fit by a Band function with 
Epeak = 207 (+22/-17) keV, alpha = -0.69 +/- 0.07, and 
beta = -2.3 (+0.2/-0.3) 
(C-Stat 724.6 for 481 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(1.38 +/- 0.05)E-05 erg/cm^2. The 1-sec peak photon flux measured 
starting from T0+11.3 s in the 8-1000 keV band is 5.1 +/- 0.4 ph/s/cm^2.

During this burst, A0535+262 (currently in a bright outburst at an 
intensity of ~3xCrab 12-50 keV) and the Crab rose from Earth 
occultation, causing a significant rise in the background level. This 
likely adds additional systematic errors to the results, especially T90.

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


GRB_name: GRB091221A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10294
SUBJECT: GRB 091221: Skynet/PROMPT Detections
DATE:    09/12/23 22:11:00 GMT
FROM:    Josh Haislip at U.North Carolina  <haislip@physics.unc.edu>

J. Haislip, D. Reichart, K. Ivarsen, A. LaCluyze, R. Egger, A. Foster, J. 
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. 
Nysewander report:

Skynet observed the Swift/BAT localization of GRB 091221 (Palmer et al., 
GCN 10283) with four of the 16" PROMPT telescopes at CTIO beginning 4.3 
hours after the trigger in BVRI.

We detect the afterglow (Palmer et al., GCN 10283; Zheng et al., GCN 
10284).  Stacking only images that increase the limiting magnitude yields:

mean                                                       1-sig. 1-sig.
time                                                       sys.   stat.
since                                          cal.        cal.   cal.
trig. tel.     exp.     fil. magnitude         stars       unc.   unc.
(h)            (# x s)                                     (mag)  (mag)

4.9   PROMPT-5 44 x 80  I    > 21.1 (3 sigma)  143 USNO B1 0.338  0.000
            + 1 x 40
4.9   PROMPT-4 42 x 80  R    21.49 +0.27 -0.22 139 USNO B1 0.362  0.000
4.9   PROMPT-3 41 x 80  B    > 21.5 (3 sigma)  82 USNO B1  0.154  0.000
4.9   PROMPT-1 41 x 80  V    21.41 +0.42 -0.31 27 NOMAD    0.193  0.000
7.3   PROMPT-3 136 x 80 B    > 22.1 (3 sigma)  79 USNO B1  0.153  0.000
7.3   PROMPT-5 134 x 80 I    > 21.8 (3 sigma)  120 USNO B1 0.337  0.000
7.3   PROMPT-4 139 x 80 R    22.44 +0.38 -0.28 112 USNO B1 0.392  0.000
7.4   PROMPT-1 145 x 80 V    > 22.0 (3 sigma)  28 NOMAD    0.112  0.000


GRB_name: GRB091221A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10295
SUBJECT: GRB 091221 : IRSF NIR upper limit
DATE:    09/12/25 14:42:23 GMT
FROM:    Kenta Nishimoto at Nagoya U/MOA-II  <nishimo@stelab.nagoya-u.ac.jp>

K. Nishimoto, T. Sako, H. Naito, D. Suzuki (Nagoya Univ.) on behalf of
the MOA Collaboration,
M. Kurita (Nagoya Univ.), Y.Ita (NAOJ) on behalf of the IRSF Collaboration
report:

We searched for a NIR afterglow of GRB 091221 (GCN 10283, Krimm et al.)
starting from 22:27:49.7 UT on 2009 Dec 21 (95 minutes after the burst)
with the SIRIUS on the IRSF 1.4m telescope at SAAO in South Africa.
In images of a 150sec exposure with J, H and Ks filters, we did not find
any object within the error circle of the Swift XRT source position (
GCN 10287, Evans et al.)

Three sigma upper limits are the followings.

J > 19.5
H > 18.4
K > 17.0

This photometry was done by using the DoPhot and calibrated against the
2MASS cataloged stars.


GRB_name: GRB091230A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10298
SUBJECT: GRB 091230: a long GRB detected by INTEGRAL
DATE:    09/12/30 07:57:12 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

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

A  GRB with duration of about 120  s has been detected by IBAS in
IBIS/ISGRI data at 06:27:30 UT on December 30.

The refined coordinates (J2000) are:

RA:  132.9146 [degrees]  
DEC: -53.8825  [degrees]

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

A plot of the light curve will be posted at

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

This message can be cited.


GRB_name: GRB091230A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10299
SUBJECT: GRB 091230: GROND optical/NIR afterglow candidate
DATE:    09/12/30 13:00:36 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

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

We observed the field of GRB 091230 (INTEGRAL trigger #5967, D. Gotz et
al., GCN #10298) simultaneously in g'r'i'z'JHK with GROND mounted at the 
2.2m ESO/MPI telescope at La Silla Observatory (Chile).

Observations started on 30 Dec. 2009 at 06:30:27 UT, 2.9 min after the
burst.

Image subtraction reveals a variable point source inside the INTEGRAL
error circle (D. Gotz et al., GCN #10298) at

RA (J2000) = 08:51:39.18
DEC (J2000) = -53:53:52.7

with an uncertainty of 0.5" in each coordinate. This is 56" from the
refined INTEGRAL position.

Preliminary photometry yields the following magnitudes in stacked images:

Filter  T_mid[s] Exp[s]  AB Mag  MagErr
---------------------------------------
g'      390       4x 66  21.63   0.07
r'      390       4x 66  20.76   0.04
i'      390       4x 66  20.45   0.05
z'      390       4x 66  20.22   0.05
J       403      24x 10  19.75   0.12
H       403      24x 10  19.58   0.14
K       403      24x 10  19.26   0.15


The quoted error is statistical only. There is an additional systematic
error in the absolute calibration using the GROND zeropoints and 2MASS
field stars which is expected to be in the 0.1 to 0.2 mag range.

The object fades by two magnitudes to r' = 22.8  0.1 until the end of
our optical observations two hours after the trigger - thus we propose
this object as the optical/NIR afterglow of GRB 091230.


GRB_name: GRB091230A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10300
SUBJECT: GRB 091230: Swift-XRT observation
DATE:    09/12/31 01:45:38 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A. P. Beardmore (U. Leicester) and H. A. Krimm (CRESST/GSFC/USRA)
report on behalf of the Swift-XRT team:

At 2009-12-30 15:25UT Swift performed a TOO observation of the
INTEGRAL discovered long GRB 091230 (Gotz et al.,  GCN Circ. 10298).
In 3.7 ks of XRT Photon Counting (PC) mode data, taken from 32.3 ks to
39.4 ks after the INTEGRAL trigger, we find an X-ray source within the
INTEGRAL error circle, with a 0.3-10 keV count rate of 0.01 count/s.
Using 1096 s of PC mode data and 1 UVOT image, the enhanced
XRT position for this source (using the XRT-UVOT alignment and
matching UVOT field sources to the USNO-B1 catalogue, as described by
Goad et al., 2007, A&A, 476, 1401 and Evans et al., 2009, MNRAS, 397,
1177) is: RA, Dec = 132.91150, -53.89780, which is equivalent to:

RA (J2000): 08 51 38.77
Dec(J2000): -53 53 52.0

with an uncertainty of 2.7 arcsec (radius, 90% confidence).  This
position lies 3.8 arcsec from the location of the Grond optical/NIR
afterglow candidate (Filgas et al., GCN Circ. 10299).

At this stage, we cannot tell whether the X-ray source is fading, but
its coincidence with the Grond candidate suggests it is likely the
X-ray counterpart to GRB 091230.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020124.

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


GRB_name: GRB091230A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10302
SUBJECT: GRB 091230: Swift/UVOT Observations
DATE:    09/12/31 18:50:34 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel@astro.psu.edu>

M. H. Siegel (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
091230 32291 s after the Integral detection (Gotz et al., GCN
Circ. 10298).  We do not detect the afterglow reported by GROND
(Filgas et al., GCN Circ. 10299) and Swift-XRT (Beardmore et al.,
GCN Cic. 10300).

Preliminary 3-sigma upper limits are:

FILTER     T_start(s)  T_stop    Exposure     Mag/3UL
=============================================================
white      32291        42824     3898        >22.2

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.36 (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB091231A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10304
SUBJECT: GRB 091231: GROND NIR observations
DATE:    10/01/01 10:35:38 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

R. Filgas (MPE Garching), S. Klose (TLS Tautenburg), and J. Greiner (MPE 
Garching), report on behalf of the GROND team:

GROND (Greiner et al. 2008, PASP 120, 405), the 7-channel imager mounted 
at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile), started 
follow-up NIR observations of GRB 091231 (Markwardt et al. 2009, GCN 
10301) on Jan 1, at 9:04 UT (about 15 hrs after the burst, shortly before 
sun rise).

We could not detect the afterglow candidate reported by Holland et al. 
(2009; GCN 10303). Based on a 4 min exposure, we estimate the following 
preliminary upper limits (in the Vega system):

J  > 16.7
H  > 16.3
K  > 15.2

using GROND zeropoints and the 2MASS catalog.

Due to visibility constraints of the field from La Silla, no earlier 
observations were possible.


GRB_name: GRB100103A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10307
SUBJECT: GRB 100103A: a long GRB detected with INTEGRAL
DATE:    10/01/03 18:45:15 GMT
FROM:    Diego Gotz at CEA  <diego.gotz@cea.fr>

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

a long gamma ray burst has been detected by IBAS in the IBIS/ISGRI  
data at 17:42:32 U.T. on January 3rd. It lasts about 40 s and its  
refined coordinates (J2000) are:
R.A.:     112.366 [degrees]
DEC.:    -34.482 [degrees]

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

A preliminary analysis gives a peak flux in the 20-200 keV range of  
about 3.5 ph/cmsq/s (1 s integration time) and a fluence over the same  
energy range of about  3e-6 erg/cmsq.

A plot of the light curve will be posted at

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

This message can be cited.


GRB_name: GRB100103A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10308
SUBJECT: GRB 100103A: Swift/XRT position
DATE:    10/01/03 21:58:26 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>

J. A. Kennea (PSU) and W. H. Baumgartner (GSFC/UMBC) report on behalf of 
the Swift Team:

Swift began a target of opportunity observation of the INTEGRAL detected 
GRB 100103A (GCN #10307), at 18:36UT on January 3rd, 2010, approximately 
54 mins after the INTEGRAL detection. In approximately 2.5 ks of Photon 
Counting mode data, we find an uncatalogued source in the XRT field of 
view with a preliminary position of RA, Dec (J2000) = 112.37327, 
-34.487811, which is equivalent to:

RA(J2000)  =  07h 29m 29.5s
Dec(J2000) = -34d 29' 16.1"

with an estimated uncertainty of 6 arcmins radius (90% confidence). This 
position lies 0.5 arcmins from the INTEGRAL reported position. We 
currently cannot confirm if this source is fading.


GRB_name: GRB100103A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10309
SUBJECT: GRB 100103A: Correction to Swift position error
DATE:    10/01/03 22:04:21 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>

J. A. Kennea (PSU) and W. H. Baumgartner (GSFC/UMBC) report on behalf of
the Swift Team:

The position error in GCN #10308 should be "6 arcseconds radius (90% 
confidence)". We apologize for the error.


GRB_name: GRB100103A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10310
SUBJECT: GRB 100103A:  Swift/UVOT Upper Limits
DATE:    10/01/03 23:57:10 GMT
FROM:    Margaret Chester at PSU  <chester@astro.psu.edu>

M. M. Chester (PSU), M. H. Siegel (PSU), S. Immler (NASA/CRESST/GSFC),  
and W. H. Baumgartner (GSFC/UMBC) report on behalf of the Swift/UVOT  
team:

The Swift/UVOT began observing the INTEGRAL-detected GRB 100103A  
(D.Gotz, et al., GCN Circ. 10307) at 18:36UT on January 3rd, 2010,  
approximately 54 mins after the INTEGRAL detection.  No optical  
afterglow consistent with the Swift/XRT candidate (J. Kennea, et al.,  
GCN Circ. 10308) is detected in the UVOT exposures.  Preliminary 3- 
sigma upper limits using the UVOT photometric system (Poole et al.  
2008, MNRAS, 383, 627) are:

Filter    T_start(s)   T_stop(s)   Exp(s)      Mag
----------------------------------------------------------------
v         3244         4409        1165       >20.44
u         4418         5554        1136       >20.70


The values quoted above are not corrected for the Galactic extinction  
due to the reddening of E(B-V) = 0.29 in the direction of the XRT  
candidate (Schlegel et al. 1998).


GRB_name: GRB100103A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10311
SUBJECT: Konus-Wind observation of GRB 100103A
DATE:    10/01/04 20:02:23 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100103A (Gotz et al., GCN 10307)
triggered Konus-Wind at T0=63766.807s UT (17:42:46.807).

The burst light curve shows a single-pulse structure
with a duration of ~50 s. There is a hint of the soft
extended emission which lasts to ~250 s after T0.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100103_T63766/

As observed by Konus-Wind the burst
had a fluence of 1.2(+/-0.2)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+7.168s
of 0.9(+/-0.1)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst (from T0 to T0+41.216 s)
is well fitted in the 20 keV - 2 MeV range by GRB (Band) model for which:
the low-energy photon index alpha = -0.91 (-0.38,+0.63),
the high energy photon index beta = -2.2(<-1.9),
the peak energy Ep = 157(-51, +83)keV (chi2 = 45/57 dof).

The spectrum of the most intense part of the burst (from T0 to T0+8.448 s)
is well fitted in the 20 keV - 2 MeV range by GRB (Band) model for which:
the low-energy photon index alpha = -0.82 (-0.25,+0.28),
the high energy photon index beta = -2.7(<-2.2),
the peak energy Ep = 204(-38, +56)keV (chi2 = 54.8/57 dof).

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


GRB_name: GRB100103A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10312
SUBJECT: GRB 100103A - UVOT-enhanced XRT position
DATE:    10/01/05 07:35:56 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

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

Using 3971 s of XRT Photon Counting mode data and 2 UVOT images for the 
INTEGRAL burst GRB 100103A, 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 = 112.37270, -34.49020 which is equivalent 
to:

RA (J2000):  07 29 29.46
Dec (J2000): -34 29 24.9

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

This position may be improved as more data are received.  The latest 
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position 
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans 
et al. (2009, MNRAS, 397, 1177).

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


GRB_name: GRB100103A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10313
SUBJECT: GRB 100103A: Swift-XRT team refined analysis 
DATE:    10/01/06 13:49:35 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page (U. Leicester) and W.H. Baumgartner (GSFC/UMBC) report on behalf 
of the Swift-XRT team: 

We have analysed 8 ks of XRT data for the INTEGRAL GRB 100103A (Gotz et 
al. GCN Circ. 10307) obtained during two observations, from 3.3-10.3 ks 
and 196-224 ks after the trigger. The source found by Kennea & Baumgartner 
(GCN Circ. 10308; improved position given by Page et al. in GCN Circ. 
10312) is now clearly fading, with a decay slope of alpha = 0.87 (+0.14, 
-0.10). We therefore confirm that this is, indeed, the X-ray afterglow.

A spectrum formed from the PC mode data can be fitted with an absorbed 
power-law with a photon spectral index of 2.86 (+0.32, -0.30). The 
best-fitting absorption column is 6.5 (+1.3, -0.7) x 10^21 cm^-2, in 
excess of the Galactic value of 2.4 x 10^21 cm^-2 (Kalberla et al. 2005). 
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor 
deduced from this spectrum is 3.9 x 10^-11 (1.7 x 10^-10) erg cm^-2 
count^-1. 

The results of the XRT-team automatic analysis are available at 
http://www.swift.ac.uk/xrt_products/00020125.

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


GRB_name: GRB100103A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10314
SUBJECT: GRB 100103A: GROND Upper Limits
DATE:    10/01/07 13:08:48 GMT
FROM:    Jochen Greiner at MPI  <jcg@mpe.mpg.de>

R. Filgas, F. Olivares, J. Greiner, T. Kruehler (all MPE Garching)
and S. Klose (Tautenburg Observatory) report on behalf of the GROND team:

We observed the field of GRB 100103A (INTEGRAL trigger #5970; Gotz et al.,
GCN #10307) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP, 120, 405) mounted at the 2.2 m ESO/MPI telescope at La
Silla Observatory (Chile). Observations started on January 4, 2010 at
00:48 UT, 7.1 hours after the GRB trigger. They were performed at
variable seeing of 2-3" and at an average airmass of 1.4.

No source is found within the 1.7" XRT error circle (Page et al., GCN #10312).
Comparison to the Digital Sky Survey and 2MASS also reveals no new sources
within a 10 arcsec surrounding. Co-added images of 24.6 min of integration time
in g'r'i'z' and 20 min in JHK, centered at 01:29 UT yield the following 
specific upper limits (AB system):

g' > 24.9
r' > 24.2
i' > 23.6
z' > 23.8
J > 21.2 
H > 20.6 
K > 19.2 

calibrated against USNO and 2MASS field stars. No correction for the Galactic
foreground extinction was made, which correspond to a reddening of 
E(B-V)=0.29 mag in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB100111A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10317
SUBJECT: GRB 100111A: Swift detection of a burst with an optical afterglow
DATE:    10/01/11 04:24:29 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

L. Vetere (PSU), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), C. Gronwall (PSU),
D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC),
E. A. Hoversten (PSU), C. B. Markwardt (CRESST/GSFC/UMD),
C. Pagani (PSU), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on
behalf of the Swift Team:

At 04:12:49 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100111A (trigger=382399).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 247.038, +15.557 which is 
   RA(J2000) = 16h 28m 09s
   Dec(J2000) = +15d 33' 25"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a small precursor
peak followed by a main FRED peak for a total duration of about 30 sec. 
The peak count rate was ~3800 counts/sec (15-350 keV), at ~1 sec after
the trigger. 

The XRT began observing the field at 04:13:52.1 UT, 63.0 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 247.04766, 15.55090 which is equivalent
to:
   RA(J2000)  = 16h 28m 11.44s
   Dec(J2000) = +15d 33' 03.2"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 40 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 (4.09e+20
cm^-2, Kalberla et al. 2005), with an excess column of 2 (+2.19/-1.28)
x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 67 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 16:28:11.60 = 247.04833
  DEC(J2000) = +15:33:02.3  = 15.55064
with a 90%-confidence error radius of about 0.62 arc sec. This position is 3.4
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.58 with a 1-sigma error of about 0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.05. 

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


GRB_name: GRB100111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10318
SUBJECT: GRB 100111A: NOT optical observations
DATE:    10/01/11 09:43:35 GMT
FROM:    Johan U. Fynbo at U.Copenhagen  <jfynbo@astro.ku.dk>

D. Xu (WIS, DARK/NBI), N. Tanvir (U. Leicester), J.P.U. Fynbo (DARK/NBI),
P. Jakobsson (Univ. of Iceland), T. Liimets (NOT) report on behalf of a
larger collaboration:

We observed the field of GRB100111A (Vetere et al., GCN 10317) with the
Nordic Optical Telescope equipped with ALFOSC. A 30 s R-band frame was
obtained, starting at 05:25:45 UT on Jan 11, 73 min after the
burst trigger. The afterglow is clearly detected in the frame with
R=19.46+/-0.05 mag calibrated with the nearby #1055-0262005 star in the
USNO B1 catalog.


GRB_name: GRB100111A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10319
SUBJECT: GRB 100111A: Fermi GBM observation
DATE:    10/01/11 16:24:31 GMT
FROM:    Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>

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

"At 04:12:49.70 UT on 11 January 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100111A (trigger 284875971 / 100111176)
which was also detected by the Swift-BAT (Vetere et al. 2010, GCN 10317).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 32 degrees.

The GBM light curve consists of one main pulse
with a duration of about 12 s (8-1000 keV).
The time-averaged spectrum from T0-2.7 s to T0+5.5 s is
adequately fit by a simple power law function
with index -1.66 (+0.05/-0.06) (CSTAT 452 for 363 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.5 +/- 0.1 )E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.003 s in the 8-1000 keV band
is 3.5 +/- 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: GRB100111A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10320
SUBJECT: GRB100111A: Swift-XRT refined analysis
DATE:    10/01/11 16:53:52 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

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


We have analysed 774 s of XRT data for GRB 100111A (Vetere et al.
GCN Circ. 10317), from 77 s to 852 s after the BAT trigger. The
data are entirely in Photon Counting (PC) mode. The light curve
can be modelled with a power-law decay with a decay index of
alpha=0.58 +/- 0.16.

A spectrum formed from the PC mode data can be fitted with an
absorbed power-law with a photon spectral index of 2.10 (+0.29,
-0.26). The best-fitting absorption column is 1.7 (+0.8, -0.7) x
10^21 cm^-2, in excess of the Galactic value of 4.1 x 10^20 cm^-2
(Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10
keV flux conversion factor deduced from this spectrum is 3.8 x
10^-11 (5.7 x 10^-11) erg cm^-2 count^-1.

If the light curve continues to decay with a power-law decay index
of 0.58, the count rate at T+24 hours will be 0.023 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.7 x
10^-13 (1.3 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/00382399.

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


GRB_name: GRB100111A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10321
SUBJECT: GRB 100111A: Enhanced Swift-XRT position
DATE:    10/01/11 17:24:58 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 5361 s of XRT Photon Counting mode data and 10 UVOT
images for GRB 100111A, 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 = 247.04845, +15.55083 which is equivalent
to:

RA (J2000): 16h 28m 11.63s
Dec (J2000): +15d 33' 03.0"

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: GRB100111A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10322
SUBJECT: GRB 100111A: Swift-BAT refined analysis
DATE:    10/01/11 20:16:16 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU),
L. Vetere (PSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100111A (trigger #382399)
(Vetere, et al., GCN Circ. 10317).  The BAT ground-calculated position is
RA, Dec = 247.029, 15.539 deg which is 
   RA(J2000)  =  16h 28m 06.9s 
   Dec(J2000) = +15d 32' 19.1" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted light curve shows a weak peak at ~T-30 sec and the main
FRED-like peak from ~T-10 sec and ending at ~T+25 sec.  T90 (15-350 keV)
is 12.9 +- 2.1 sec (estimated error including systematics).
 
The time-averaged spectrum from T-7.5 to T+8.7 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.69 +- 0.13.  The fluence in the 15-150 keV band is 6.7 +- 0.5 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.03 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/382399/BA/


GRB_name: GRB100111A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10323
SUBJECT: GRB 100111A: Swift UVOT Refined Analysis 
DATE:    10/01/11 21:17:29 GMT
FROM:    Erik Hoversten at Swift/Penn State  <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) and L. Vetere (PSU) report on behalf of the
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100111A
67 s after the BAT trigger (Vetere, et al., GCN Circ. 10317). A source
is detected at 17.62 magnitudes in the initial white finding chart at
the position RA, Dec (J2000) = 247.04833, 15.55064 which is equivalent
to:

    RA(J2000)  =  16:28:11.60 = 247.04833
    DEC(J2000) = +15:33:02.3  = 15.55064

with a 90%-confidence error radius of about 0.51 arc sec. This
position is 0.8 arcsec from the UVOT-enhanced XRT position (Beardmore,
et al. GCN Circ. 10321) and the two positions agree within the error
bars.  The source faded by more than a magnitude in the white filter
over the first orbit of observations.  Additionally the source is
detected in the b, u, and uvw1 filters, with a marginal 2.4-sigma
detection in v and a 2.1-sigma detection in uvm2. Given the detection
in the uvw1 filter the redshift of this burst is less than 1.9.

The observed magnitudes and 3-sigma upper limits using the UVOT
photometric system (Poole et al. 2008, MNRAS, 383, 627) for the
initial exposures are:

Filter   T_start(s)   T_stop(s)   Exp(s)          Mag
=============================================================
white        67          217        147      17.62 +/- 0.05
white       858         1007        147      18.73 +/- 0.10
v           609         1057         58         > 18.41
b           535          727         39      18.76 +/- 0.27
u           279          529        245      17.37 +/- 0.07
uvw1        658          851         38      18.57 +/- 0.36
uvm2        633          827         38         > 18.99
uvw2        584         1033         58         > 19.04

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB100111A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10324
SUBJECT: GRB 100111A: PAIRITEL NIR Upper Limits
DATE:    10/01/11 22:35:56 GMT
FROM:    Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>

A. N. Morgan, S. B. Cenko, J. S. Bloom, (UC Berkeley), report:

We observed the field of GRB 100111A (Vetere et al., GCN 10317) with
the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began
at 2010-01-11 12:20:11 UT, ~8.12 hours after the Swift trigger.
Observations were taken under good weather conditions but at high
airmass before dawn.  In mosaics (effective exposure time of ~2223
seconds) taken simultaneously in the J, H, and Ks filters, we do not
detect the optical afterglow (Vetere et al., GCN 10317; Xu et al., GCN
10318; Hoversten et al., GCN 10323).

The preliminary photometry yields:

post_burst
t_mid(h)    exp(s)  filt    U. Limit (3 sig)
8.60        2223    J       > 19.0
8.60        2223    H       > 18.5
8.60        2223    Ks      > 18.0

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


GRB_name: GRB100115A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10325
SUBJECT: GRB 100115A detected in ground analysis of Swift-BAT data
DATE:    10/01/15 22:11:11 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>

J. R. Cummings (NASA/GSFC/UMBC), N. Gehrels (NASA/GSFC),
H. A. Krimm (NASA/GSFC/USRA), D. M. Palmer (LANL) report on
behalf of the Swift Team:

At 11:15:19UT, BAT detected GRB 100115A during a preplanned Swift
slew maneuver. A source was found in ground analysis of event data
collected for the BAT Slew Survey at RA, Dec 3.333, -0.817, which is

RA (J2000) 00 13 19.9
Dec (J2000) -00 49 01

with an estimated 90% containment uncertainty of 4 arcmin radius.

The burst was a single FRED pulse with a T90 of about 3 seconds.
There was no detectable flux above 100 keV.

A Swift TOO has been approved.


GRB_name: GRB100115A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10326
SUBJECT: GRB 100115A: Swift-XRT candidate afterglow
DATE:    10/01/16 10:59:04 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti (INAF-OAB), B. Sbarufatti (OAB), J. R. Cummings 
(NASA/GSFC/UMBC),
M. De Pasquale (MSSL/UCL) report on behalf of the Swift-XRT team:

Swift began observing the field of the Swift BAT Slew Survey (BATSS)
GRB 100115A (Cummings et al. GCN Circ. 10325) 40ks  after the trigger.
Using 2.5 ks of XRT Photon Counting mode data we detect a single
X-ray source source inside the BAT error circle at
RA, DEC= 3.3664, -0.8263 which is equivalent to:

RA (J2000): 00h 13m 27.93s
Dec (J2000): -00d  49' 34.8"

with an uncertainty of 6.8 arcsec (radius, 90% confidence).

The source is detected at a level of 6.6x10^-3 count sec^-1.
Given the current statistics it is not possible to determine whether
this source is fading.

A tentative spectrum formed from the PC mode data can be fitted with
an absorbed power-law with a photon spectral index of 2.7 (+1.7, -0.8). The
best-fitting absorption column is  consistent with the Galactic value
of 3.1 x 10^20 cm-2 (Kalberla et al. 2005). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 2.9 x 10^-11 (3.6 x 10^-11) erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020126.

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


GRB_name: GRB100115A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10327
SUBJECT: GRB 100115A: Swift/UVOT Upper Limits
DATE:    10/01/16 13:07:40 GMT
FROM:    Patricia Schady at MSSL/Swift  <msslba@googlemail.com>

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

The Swift/UVOT began observerving the field of Swift BAT Slew
Survey (BATSS) GRB 100115A (Cummings et al. GCN Circ. 10325) 40ks
after the BAT trigger. We do not detect any source at the candidate
Swift XRT position (Margutti et al. GCN Circ. 10326).

The 3 sigma upper limits for the summed images are reported below:

Filter    T_start(s)  T_stop(s)  Exposure   Mag(3 sgma UL)
###########################################################
b           40636      46609       411        >20.19
u     40423      46395       411        >19.85
uvw1     40001      46180       824        >20.29
uvw2     40849      47260       1098       >20.99
###########################################################

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.06 mag (Schlegel et al.,
1998, ApJS, 500, 525).  The photometry is on the UVOT photometric system
described in Poole et al. (2008, MNRAS, 383,627).


GRB_name: GRB100115A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10328
SUBJECT: GRB 100115A: SARA Afterglow Candidate
DATE:    10/01/16 21:28:38 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Dieter H. Hartmann (Clemson University) and Robert
Berrington (Ball State University) report:

We observed the field of the Swift-detected GRB 100115A (Cummings et al.,
GCN 10325) with the 0.9m SARA telescope located at Kitt Peak National
Observatory beginning 15 hours and 20 minutes after the BAT detection
under good conditions.  In a single 1200 sec exposure, we detect a source
within the XRT error circle (Margutti et al., GCN 10326) around R ~ 22 mag
(as compared to USNO B.1 catalog field stars).  There is no corresponding
counterpart in either SDSS or Sloan.  The Sloan survey goes deeper than
our image, indicating the new source in the XRT error circle is a
potential candidate for the afterglow of GRB 100115A.  No statement about
variability can be made at this time; further observations are encouraged.


GRB_name: GRB100115A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10329
SUBJECT: NOT observation of GRB100115A localization
DATE:    10/01/17 01:27:15 GMT
FROM:    Martin Jelinek at Inst.Astrophys.Andalucia,Granada  <mates@iaa.es>

Martin Jelinek (IAA CSIC Granada), Petr Kubanek (IPL Valencia)
and Javier Gorosabel, Antonio J. Delgado (IAA CSIC) on behalf
of a larger colaboration.

report:

We observed the Swift-XRT errorbox of the GRB100115A (Margutti
et al. GCN 10326) with the 2.56 Nordic Optical Telescope at La
Palma. We acquired 7x 300s i' band exposure at about 32 hours
after the GRB. The detection limit of this image is about i' =
24.0 mag.

We detect four sources within or at the border of the X-ray
errorbox. None of these objects is present in the SDSS DR7
image, with the exception of A, which could be believed to be
at the its very detection limit. This object also seems in our
image extended and/or composed of two components.

Given the lack of astrometric information in the Updike et al.
(GCN 10328) we cannot confirm or decide whether one of these
objects is an optical afterglow of GRB100115A. We however do
not see any object as bright as previously reported, which
might confirm the decaying behaviour of the afterglow
candidate by SARA.

The identification card with the objects marked A, B and C
can be downloaded from
http://www.iaa.es/mates/grb100115a-not-errorbox.jpg

This message may be cited.


GRB_name: GRB100116A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10330
SUBJECT: GRB 100116A: Fermi GBM detection
DATE:    10/01/17 02:29:49 GMT
FROM:    Michael S. Briggs at UAH and MSFC  <michael.briggs@nasa.gov>

M. S. Briggs and V. Connaughton (UA Huntsville),
report on behalf of the Fermi GBM Team:

"At 21:31:00.24 UT on 16 January 2010, the Fermi Gamma-ray Burst Monitor
(GBM) triggered and located GRB 100116A (trigger 285370262 / 100116.897).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 301.48, Dec = +16.24 (J2000 degrees, equivalent to
J2000 20h 06m, +16d 14'), with a statistical 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 29 degrees.

The GBM light curve shows two peaks separated by over 60 seconds with
little or no intervening emission.  The total duration is approximately
110 seconds.  Both peaks are best fit with a power law function with an
exponential high-energy cutoff.   The first peak, fit from -3.072 to
2.048 s, has Epeak = 240 (-40,+60) keV and an index of -0.92 +/- 0.15.
The fluence of this peak is (1.5 +/- 0.1) E-6 ergs / cm**2.  The second
peak, fit from 82.949 to 101.38 s, has Epeak = 1240 +/- 90  keV and an
index of -1.02 +/- 0.017.   The fluence of this peak is
(3.36 +/- 0.03) E-5 ergs / cm**2.

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


GRB_name: GRB100115A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10331
SUBJECT: GRB100115A: Revision of NOT observation
DATE:    10/01/17 03:10:10 GMT
FROM:    Martin Jelinek at Inst.Astrophys.Andalucia,Granada  <mates@iaa.es>

Martin Jelinek (IAA CSIC Granada), Petr Kubanek (IPL Valencia)
and Javier Gorosabel, Antonio J. Delgado (IAA CSIC) on behalf
of a larger colaboration.

report:

In light of the new XRT improved position we reexamined the
NOT image from our previous report (Jelinek et al., GCN 10329)
and found that only the (extended) object A at

 00:13:28.12 -00:49:32.6 +-2" (J2000)

stays within the XRT errorbox and may be possibly related to
the GRB100115A, either as its afterglow, host galaxy or a
combination of both.

The improved identification card can be downloaded from
http://www.iaa.es/~mates/grb100115a-not-errorbox2.jpg

We thank Alex Kann for pointing out the new XRT position. 

This message may be cited.


GRB_name: GRB100115A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10332
SUBJECT: GRB 100115A: SARA Astrometry
DATE:    10/01/17 04:56:47 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. Alexander Kann (TLS Tautenburg), Adria C. Updike and Dieter H. Hartmann 
(Clemson University) report:

We performed astrometry (against the USNO-B1.0 catalog) on the image of 
the field of GRB 100115A (Cummings et al., GCN 10325) taken by the 0.9m 
SARA observatory at KPNO, which revealed a possible afterglow candidate 
(Updike et al., GCN 10328).

For this object, we derive a position of (conservative error 1"):

RA (J2000):    00:13:28.05
Dec. (J2000): -00:49:32.4

in full agreement with the position given for Object "A" by Jelinek et al. 
(GCN 10331), and possibly closer to (or identical with) the brighter 
southwest component of Object "A".

Given the lack of photometric information in Jelinek et al. (GCN 10331) we 
cannot confirm if the SARA candidate has faded significantly, but note 
that, in the SARA image, the afterglow candidate is about as bright as the 
star to the southwest at RA (J2000): 00:13:27.20, Dec. (J2000): -00:49:42.4, and it 
seems to be much fainter than this source (note the different filters, 
though) in the Jelinek finding chart.

This message may be cited.


GRB_name: GRB100116A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10333
SUBJECT: GRB 100116A: Fermi LAT detection
DATE:    10/01/17 05:04:12 GMT
FROM:    Julie McEnery at NASA/GSFC  <julie.e.mcenery@nasa.gov>

Julie McEnery (GSFC), Jim Chiang (SLAC), Nicola Omodei (Stanford) and
Tak Nakamori (Tokyo Institute of Technology) report on behalf of the 
Fermi LAT team:

At 21:32:36.00 (UT) on 16 Jan 2010, the Fermi Large Area Telescope
(LAT) detected gamma rays from the long GRB 100116A, which was
triggered and located by the Fermi Gamma-ray Burst Monitor (GBM)
(trigger 285370262 / 100116.897, GCN10330). The angle of the GBM best
position (RA, Dec= 301.48, 16.24) with respect to the LAT boresight was
~29 degrees at the time of the LAT detection, which is well within our
field of view.

The data from the Fermi LAT shows an increase in the event rate coincident
with the second peak in the GBM lightcurve (around 90s after the GBM 
trigger)
that is spatially correlated with the GBM emission. It is a relatively weak
detection with less than 20 excess events, most with energy below 100 MeV.

The best LAT on-ground localization is found to be (RA, Dec = 305.02,
14.45) (RA=20h 20' 04.80'', Dec=14d 27' 00.0'', J2000) with a 90%
containment radius of 0.30 deg (statistical; 68% containment radius: 
0.17 deg)
which is consistent with the GBM localization.

A Swift TOO request cannot be requested due to Sun constraints.

Further analysis is ongoing.

The point of contact for this burst is

Julie McEnery: julie.mcenery@nasa.gov

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

This message can be cited.


GRB_name: GRB100115A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10334
SUBJECT: GRB 100115A: Enhanced Swift-XRT position
DATE:    10/01/17 10:18:01 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti (INAF-OAB), P.A. Evans and M.R. Goad (U. Leicester) report
on behalf of the Swift-XRT team:

Using 1321 s of XRT Photon Counting mode data and 1 UVOT 
images, we find an astrometrically corrected X-ray position (using the
XRT-UVOT alignment and matching UVOT field sources to the USNO-B1
catalogue): RA, Dec =3.36730, -0.82650 which is equivalent to:

RA (J2000):  00 13 28.16
Dec (J2000): -00 49 35.4

with an uncertainty of 4.0 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 is an official product of the Swift-XRT team.


GRB_name: GRB100115A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10335
SUBJECT: GRB 100115A: Gemini-N photometry
DATE:    10/01/17 16:53:52 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara, D. B. Fox (PennState), E. Berger (Harvard U.)
report on behalf of a larger collaboration:

"On January 16.20 UT we observed the field of GRB100115A
(Cummings et al. 10325, Margutti et al. GCN 10326) with the
Gemini-North GMOS camera in r and g bands.
We collected a sequence of 5x180s images in each filter.
In the coadded images the afterglow candidate is visible in
both filters (GCN 10328,10331,10332).

On January 17.20 UT we collected a second epoch with the same set-up.
The following magnitude have been calibrated using the USNO-B1.0
star at RA: 00:13:30.44 Dec: -00:49:16.93 ( = 19.76 mag):

Jan. 16.20 UT:
r = 21.37 +- 0.08 mag

Jan 17.20 UT:
r = 21.86 +- 0.08 mag

A similar fading of ~0.5 mag is present in our g-band observations.
Therefore we conclude that Object "A", which shows two structures,
contains a fading transient. Further observation are planned.

We thank the Gemini staff, in particular Sandy Leggtt, for performing these
observations.


GRB_name: GRB100117A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10336
SUBJECT: GRB 100117A: Swift detection of a short hard burst
DATE:    10/01/17 21:19:26 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. De Pasquale (UCL-MSSL), S. D. Barthelmy (GSFC),
D. N. Burrows (PSU), S. Campana (INAF-OAB), P.A. Curran (MSSL-UCL),  
N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
V. Mangano (INAF-IASFPA), R. Margutti (Univ Bicocca&OAB),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
C. Pagani (PSU), D. M. Palmer (LANL), P. Romano (INAF-IASFPA),
T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), M. Stamatikos (OSU/NASA/GSFC) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 21:06:19 UT, the Swift Burst Alert Telescope (BAT) triggered and  
located GRB 100117A (trigger=382941).  Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 11.260, -1.594 which is
   RA(J2000)  =  00h 45m 02s
   Dec(J2000) = -01d 35' 38"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty).  The BAT light curve shows a single spike   
structure with a duration of about 0.4 sec.  The peak count rate
was ~4500 counts/sec (15-350 keV), at T_zero.

The XRT began observing the field at 21:07:39.6 UT, 80.1 seconds after   
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 11.26946, -1.59620 which
is equivalent to:
   RA(J2000)  = 00h 45m 4.67s
   Dec(J2000) = -01d 35' 46.3"
with an uncertainty of 4.6 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.  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 (2.66e+20
cm^-2, Kalberla et al. 2005), with an excess column of 4 (+3.65/-2.58)
x 10^21 cm^-2 (90% confidence).

The initial flux in the 2.5 s image was 1.24e-09 erg cm^-2 s^-1 (0.2-10
keV).


UVOT took a finding chart exposure of 150 seconds with the White filter
starting 88 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag.
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02.



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


GRB_name: GRB100117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10337
SUBJECT: GRB100117A: Possible afterglow from NOT observation
DATE:    10/01/17 23:14:51 GMT
FROM:    Dong Xu at DARK,NBI  <dong@astro.ku.dk>

D. Xu (WIS, DARK/NBI), D. Malesani, G. Leloudas, J.P.U. Fynbo 
(DARK/NBI), A.A. Djupvik, R. Karjalainen (NOT), N.R. Tanvir (U. 
Leicester), P. Jakobsson (Univ. of Iceland) report on behalf of a larger 
collaboration:

We observed the field of GRB100117A (De Pasquale et al., GCN 10336) with 
the Nordic Optical Telescope equipped with StanCam and NOTCam, starting 
at 21:26:40 UT on Jan 17th, 20.35 mins after the burst trigger. The 
observations were carried out at high airmass (~2) and in poor seeing.

In a 900 s R-band image, starting at 21:48:42 UT, we notice the presence 
of a faint, marginally significant object at coordinates:

RA(J2000)=00h 45m 04.75s
Dec(J2000)=-01d 35' 47.4"

with an error circle of 0.5 arcsec. If real, its magnitude is R = 
22.5+/-0.5.

The co-addition of a series of K-band images doesn't show any convincing 
counterpart on the position.


GRB_name: GRB100117A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10338
SUBJECT: GRB 100117A: Swift-BAT refined analysis
DATE:    10/01/17 23:45:29 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

C. B. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), M. De Pasquale (UCL-MSSL), E. E. Fenimore (LANL),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+484 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100117A (trigger #382941)
(De Pasquale, et al., GCN Circ. 10336).  The BAT ground-calculated position is
RA, Dec = 11.280, -1.586 deg which is 
   RA(J2000)  =  00h 45m 07.1s 
   Dec(J2000) = -01d 35' 11.1" 
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 66%.
 
The mask-weighted light curve shows a single peak starting at T+0.0 and ending
at T+0.4 sec.  T90 (15-350 keV) is 0.3 +- 0.05 sec (estimated error including
systematics).
 
The time-averaged spectrum from T-0.0 to T+0.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
0.88 +- 0.22.  The fluence in the 15-150 keV band is 9.3 +- 1.3 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T-0.35 sec in the 15-150 keV band
is 2.9 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/382941/BA/


GRB_name: GRB100117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10339
SUBJECT: GRB 100117A: Gemini South Imaging and CFHT Pre-Explosion Images
DATE:    10/01/18 02:06:23 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

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

We have obtained pre-explosion images of the field of GRB100117A from the
Canada-France-Hawaii MegaCam archive.  Images were obtained in the g', r',
and z' filters on 26 December 2005, and in the i' filter on 12 November
2007.  Exposure times ranged from 240 s in g'-band to 500 s in i'-band.

Inside the candidate XRT afterglow localization (de Pasquale; GCN 10336),
we find four sources, with the following positions and R- and I-band
magnitudes (calibrated relative to several USNO-B1 sources in the field;
expected systematic uncertainty ~ 0.3 mag):

Source  RA  Dec (J2000)  R I
----------------------------------------------------------------------
S1 00:45:04.82  -01:35:47.7   23.1 21.0
S2 00:45:04.78  -01:35:45.5   23.6 22.9
S3 00:45:04.70  -01:35:42.0   24.5 22.9
S4 00:45:04.53  -01:35:49.2   > 24.7 23.6

We have also obtained a single epoch of acquisition imaging in i'-band of
the field with GMOS on Gemini South beginning at 00:46 on 18 January 2010
(~ 4.7 hours after the burst).  We detect only S1 in this image, at a
magnitude consistent with the value derived from the CFHT image.

Furthermore, given the uncertainty in our astrometry (~ 0.5" in each
coordinate), we believe it likely this is the same source identified by
Xu et al. (GCN 10337) at R = 22.5 +/- 0.5.  We therefore have no evidence
that this source has varied.

Further observations are planned.

We wish to thank the Gemini Observatory staff, in particular Peter Pessev,
for assistance with these observations.


GRB_name: GRB100117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10340
SUBJECT: GRB 100117A: Magellan IMACS imaging
DATE:    10/01/18 06:12:30 GMT
FROM:    Ryan Chornock at UC Berkeley  <chornock@astro.berkeley.edu>

R. Chornock, E. Berger (Harvard), R. Williams, and D. Kelson (OCIW) report:

"We observed the location of the short GRB 100117A (GCN 10336) with
IMACS on the Magellan/Baade 6.5-m telescope starting on 2010 Jan
18.042 UT (3.9 hours after the burst).  In a 1200 sec stacked R-band
image with a seeing of about 1" we detect the same four objects within the XRT
error circle (GCN 10336) found in archival CFHT images by Cenko et al. and
listed in GCN 10339.  All four objects appear to be extended in our image,
indicating that one of them may represent the GRB host galaxy.  No new sources
appear to be present within the XRT error circle, with a 3-sigma limiting
magnitude of approximately R=24.7."


GRB_name: GRB100117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10341
SUBJECT: GRB 100117A: Gemini-North upper limit
DATE:    10/01/18 07:31:14 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara, D. B. Fox (PSU), E. Berger, R. Chornok (Harvard),
A. Fruchter, J. Graham (STScI) report on a larger collaboration:


"We observed the location of the short GRB 100117A (GCN 10336) with
GMOS on the Gemini-North 8-m telescope starting on 2010 Jan 18.208 UT
(7.9 hours after the burst).  In a 2700 sec stacked r-band image with
a seeing of about 1" we detect the same four objects within the XRT
error circle (GCN 10336) found in archival CFHT images by Cenko et
al. and listed in GCN 10339 (see also GCN 10340).  As in the
Magellan/IMACS image (GCN 10340) all four objects appear to be
extended in the Gemini-North/GMOS data, indicating that one of them
may represent the GRB host galaxy.  No new sources appear to be
present within the XRT error circle, with a 3-sigma limiting magnitude
of approximately r=26.5."


GRB_name: GRB100117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10342
SUBJECT: GRB 100117A: Swift-XRT refined analysis
DATE:    10/01/18 14:44:00 GMT
FROM:    Boris Sbarufatti at INAF-IASF-Pa  <sbarufatti@ifc.inaf.it>

B. Sbarufatti, R. Margutti (INAF/OAB) and M. De Pasquale (UCL-MSSL)  
report on behalf of the Swift-XRT team:

We have analysed 5.5 ks of XRT data for GRB 100117A (De Pasquale et  
al. GCN Circ. 10336), from 69 s to 18.9 ks after the BAT trigger. The  
data comprise 180 s in Windowed Timing (WT) mode with the remainder in  
Photon Counting (PC) mode.

The best position is the SPER UVOT enhanced position: RA,Dec =  
11.2690, -1.5949
(degrees) which is equivalent to:
RA (J2000) = 00 45 4.56
Dec (J2000) = -01 35 41.7

with an uncertainty of 2.4 arcsec (radius, 90% containment).
This location is 50.8 arcseconds from the BAT ground position, inside  
the BAT
error circle.

After the initial flaring activity the light curve can be modeled with  
a power-law decay with a decay index of alpha=3.5 (+/-0.2). The  
afterglow is not detected after the first snapshot of data (ending 500  
s after the trigger), with an upper limit of 5E-3 count/sec at ~12 ks  
after the trigger

The spectrum formed from the WT mode data can be fitted with an  
absorbed power-law with a photon spectral index of 1.6 (+/-0.13). The  
best-fitting absorption column is 1.2 (+/-0.4) x 10^21 cm^-2, in  
excess of the Galactic value of 2.7 x 10^20 cm^-2 (Kalberla et al.  
2005). The observed (unabsorbed) 0.3-10 keV flux is 4.14 (4.84) x  
10^-10 erg cm^-2 s^-1.

The spectrum formed from the PC mode data can be fitted with an  
absorbed power-law with a photon spectral index of 2.3 (-0.5+0.6). The  
best-fitting absorption column is 1.1 (+1.3-0.9) x 10^21 cm^-2,  
slightly in excess of the Galactic value of 2.7 x 10^20 cm^-2  
(Kalberla et al. 2005). The observed (unabsorbed) 0.3-10 keV flux is  
2.40 (3.54) x 10^-12 erg cm^-2 s^-1.

The count-rate to flux conversion factor is 6.0E-11 erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00382941 
.

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


GRB_name: GRB100117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10343
SUBJECT: GRB 100117A: Optical object inside the revised XRT error circle
DATE:    10/01/18 16:23:10 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. Alexander Kann (TLS Tautenburg), D. Malesani (DARK/NBI), D. Xu (WIS, 
DARK/NBI) report on behalf of a larger collaboration:

Using the improved XRT position (B. Sbarufatti et al. GCN 10342) for the 
Swift short/hard GRB 100117A (M. de Pasquale et al., GCN 10336), we find 
that the afterglow candidate reported from NOT observations (D. Xu et al., 
GCN 10337), which is probably identical to source "S1" from S. B. Cenko et 
al. (GCN 10339), lies outside the error circle. We therefore consider it 
unlikely that this object is related to the GRB, also considering the lack 
of pronounced variability (S. B. Cenko et al. GCN 10339).

Of the four sources reported by S. B. Cenko et al. (GCN 10339) and 
confirmed by R. Chornock et al. (GCN 10340) and A. Cucchiara et al. (GCN 
10341), only source "S3" still lies within the new XRT error circle. 
Source S3, which is extended according to the above reports, may be the 
host galaxy of GRB 100117A, although lack of variability does not allow a 
conclusive statement.

An additional image epoch to perform image subtraction is encouraged.

This message may be cited.


GRB_name: GRB100117A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10344
SUBJECT: Swift/UVOT refined analysis of GRB100117A
DATE:    10/01/18 18:00:20 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

M. De Pasquale (MSSL/UCL), S. T. Holland (NASA/GSFC), S. Oates (MSSL) 
report, on the behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 100117A
89s after the BAT trigger (De Pasquale et al., GCN 10336). We do not
detect any source in the UVOT-enhanced XRT error circle (Sbarufatti et
al. GCN 10342) in the initial finding chart in the white filter, nor
in the other filters. We do not detect the the S3 source of Cenko
et al. (GCN 10339). UVOT magnitude 3-sigma upper limits are
reported in the following table:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
WHITE        89      238     147          > 20.4
WHITE        89    11957    1228          > 21.4
v          5589    17747    1082          > 19.8
b           557     6607     216          > 19.9
u           302     6402     442          > 19.9
uvw1       5999    18941     474          > 20.1
uvm2       5793    18652    1082          > 20.8
uvw2       5384    12757     978          > 20.9

No UVOT source has been found at the position of the NOT source
(Xu et al., GCN 10337) outside the XRT error circle.

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.02 mag
(Schlegel et al. 1998). All photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).


GRB_name: GRB100117A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10345
SUBJECT: GRB 100117A: Fermi GBM detection
DATE:    10/01/18 19:14:16 GMT
FROM:    Bill Paciesas at UAH  <bill.paciesas@nasa.gov>

W. Paciesas (UAH) reports on behalf of the Fermi GBM Team:

"At 21:06:19.66 UT on 17 January 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100117A (trigger 285455181 / 100117879)
which was also detected by the Swift-BAT (De Pasquale et al. 2010, GCN
10336).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 86 degrees.

The GBM light curve consists of one pulse
with a duration (T90) of about 0.4 s.
The time-averaged spectrum from T0-0.128 s to T0+0.256 s is
adequately fit by a power law function with an exponential
high energy cutoff. The power law index is -0.14 (+0.33 / -0.27) and
the cutoff energy, parameterized as Epeak, is 287 (+74 / -50) keV
(CSTAT 548 for 484 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(4.1 +/- 0.5 )E-07 erg/cm^2. The 0.256-sec peak photon flux measured
starting from T0-0.128 s in the 8-1000 keV band
is 6.1 +/- 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: GRB100117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10346
SUBJECT: GRB 100117A:  Gemini North spectroscopy
DATE:    10/01/19 06:55:58 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger, R. Chornock (Harvard), A. Cucchiara, D. B. Fox (PSU)
report:

"Starting on 2010 Jan 19.22 UT we used the GMOS spectrograph on the 
Gemini North 8-m telescope to obtain spectroscopic observations of
several extended objects (GCNs 10339, 10340, 10341) located inside and
near the revised XRT error circle (GCN 10342) of the short GRB 100117A
(GCN 10336).  The slit was aligned so that it covered sources S1, S2,
and S3 (GCN 10339).  Preliminary inspection of the combined 3000 sec
spectrum covering the wavelength range 4000-8000 A reveals that source
S1 is an M dwarf star.  We detect continuum emission from sources S2
and S3 redward of about 5000 and 5600 A, respectively, but no clear
emission or absorption features are identified."


GRB_name: GRB100116A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10347
SUBJECT: Konus-Wind observation of GRB 100116A
DATE:    10/01/19 13:23:06 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long hard GRB 100116A (Fermi-GBM trigger 285370262:
Briggs and Connaughton, GCN 10330;
Fermi-LAT localization: McEnery et al., GCN 10333)
triggered Konus-Wind at T0=77543.747s UT (21:32:23.747)

The burst light curve shows a single-pulse structure
with a total duration of ~30 s. A weaker precursor, reported by
Fermi-GBM (GCN 10330) is clearly seen in the low-resolution
background mode data at T0-88s.
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/GRB100116_T77543/

As observed by Konus-Wind the burst
had a fluence of 5.7(+/-0.6)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+6.144s
of 4.2(+/-0.4)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+23.296 s) is well be fitted
in the 20 keV - 10 MeV range by a power law
with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), with
alpha = -0.96(-0.06, +0.07),
and Ep = 968(-130, +163) keV (chi2 = 105/98 dof).

The spectrum of the most intense part of the burst
(measured from T0+0.256 to T0+8.192 s) is well fitted
in the 20 keV - 10 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.96(+/-0.6),
and Ep = 1015(-121, +146) keV (chi2 = 107/101 dof).

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


GRB_name: GRB100119A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10348
SUBJECT: GRB 100119A: Swift detection of a burst
DATE:    10/01/19 18:40:44 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

V. Mangano (INAF-IASFPA), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
S. Campana (INAF-OAB), P.A. Curran (MSSL-UCL),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
K. L. Page (U Leicester), J. L. Racusin (NASA/GSFC),
T. Sakamoto (NASA/UMBC), M. H. Siegel (PSU), M. C. Stroh (PSU),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 18:25:25 UT, the Swift Burst Alert Telescope (BAT) triggered and  
located GRB 100119A (trigger=383063).  Swift did not slew because
of a Sun observing constraint. 
The BAT on-board calculated location is
RA, Dec 299.327, -53.160 which is
   RA(J2000)  =  19h 57m 18s
   Dec(J2000) = -53d 09' 36"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty).  The BAT light curve shows multiple overlapping
peaks with a duration of about 25 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at T+5 sec. 

Due to an observing constraint, Swift cannot slew to the BAT position. 
There will thus be no XRT or UVOT data for this trigger. No observations 
with XRT or UVOT will be possible for approximately the next 26 days. 

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


GRB_name: GRB100117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10349
SUBJECT: GRB 100117A: candidate optical afterglow
DATE:    10/01/19 20:04:13 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan@warwick.ac.uk>

A.J. Levan (Warwick), J. Graham, A. Fruchter (STScI), N. Tanvir
(Leicester) A. Cucchiara, D. Fox (PSU), E. Berger, R. Chornock
(Harvard) report for a larger collaboration:

"We obtained a second epoch of Gemini North imaging of the short
duration GRB 100117A (De Pasquale et al. GCN 10336) beginning at
06:17 UT. A total of 2700s of observations were acquired in the
r-band.

Comparison with our first epoch of observations (Cucchiara et al.
GCN 10341) reveals that source S3 identifed by Cenko et al. (GCN
10339) has faded by 0.23 +/- 0.06 magnitudes in the timeframe between
the two epochs of observation (approximately 25 hours). This is
confirmed by image subtraction, which shows an offset from the centre
of S3 by ~0.6".

We suggest this is the afterglow of GRB 100117A. "


GRB_name: GRB091109A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10350
SUBJECT: GRB091109A: VLT/FORS2 spectroscopic redshift 
DATE:    10/01/19 22:11:33 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

Arne  Rau (MPE  Garching), Johan Fynbo (DARK), and Jochen Greiner (MPE 
Garching):

"We report on additional analysis of our VLT/FORS2 spectrum of the 
optical afterglow of GRB 091109A (Oates et al., GCN #10138, Guidorzi et 
al. GCN#10142, Oates GCN#10143, Afonso et al., GCN #10158 ).

A careful search revealed  absorption lines at 6227, 6308, and 6321 
Angstroem  which we identify with  SiII  and the CIV doublet a common 
redshift of  z=3.076 +/- 0.002.  Lyman-alpha absorption at this redshift 
is located shortwards of the blue wavelength cut-off and the earlier 
reported tentative detection at 5700A (Afonso et al., GCN #10158) is not 
confirmed."


GRB_name: GRB100119A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10351
SUBJECT: GRB 100119A: Swift-BAT refined analysis
DATE:    10/01/19 22:29:14 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
V. Mangano (INAF-IASFPA), C. B. Markwardt (GSFC/UMD), T. Sakamoto (GSFC/UMBC),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100119A (trigger #383063)
(Mangano, et al., GCN Circ. 10348).  The BAT ground-calculated position is
RA, Dec = 299.308, -53.149 deg which is 
   RA(J2000)  =  19h 57m 14.0s 
   Dec(J2000) = -53d 08' 56.7" 
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 7%.
 
The mask-weighted light curve shows several overlapping peaks starting
at ~T-30 sec, peaking at ~T+3 sec, and ending at ~T+30 sec.
T90 (15-350 keV) is 23.8 +- 4 sec (estimated error including systematics).
 
The time-averaged spectrum from T-15.8 to T+15.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.01 +- 0.06.  The fluence in the 15-150 keV band is 1.4 +- 0.0 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+2.12 sec in the 15-150 keV band
is 7.7 +- 1.0 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/383063/BA/


GRB_name: GRB100115A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10352
SUBJECT: GRB 100115A: Swift-XRT refined analysis
DATE:    10/01/20 08:55:01 GMT
FROM:    Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>

R. Margutti, B. Sbarufatti (INAF-OAB), S. Oates (MSSL/UCL),
report on behalf of the Swift-XRT team:

The Swift ToO observations of the BATSS burst GRB 100115A
(Cummings et al., GCN Circ. 10325) started  40ks  after the
trigger. The XRT data set consists of 8 ks exposure in PC mode
split into two epochs: the first observation was performed
at T0+40 ks, while a second epoch of observations was acquired
at T0+306 ks. The UVOT-enhanced XRT position was given by
Margutti et al. in GCN Circ. 10334.

In the second observation the X-ray source reported by Margutti
et al., GCN Circ.10326 has faded to a level of (1.4 +/- 0.9)e-3
count/sec corresponding to a decay index of -0.7 +/- 0.4.
This source is likely to be the afterglow of GRB 100115A.
No further observations are planned.

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.0 (+1.0, -0.5). The
best-fitting absorption column is consistent with the Galactic value
of 3.1 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum
is 3.4 x 10^-11 (3.8 x 10^-11) erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020126.

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


GRB_name: GRB100116A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10353
SUBJECT: GRB 100116A: Suzaku WAM observation of the prompt emission
DATE:    10/01/21 13:06:25 GMT
FROM:    Takeshi Uehara at Hiroshima U  <uehara@hirax7.hepl.hiroshima-u.ac.jp>

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

The long GRB 100116A (Fermi/GBM trigger #285370262 / 100116.89 
Briggs et al., GCN 10330, McEnery et al., GCN 10333) triggered the Suzaku 
Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV 
at 21:31:00.15 UT (=T0).

The observed light curve shows two separated pulses, a precursor at T0+0 to T0+4 sec 
and a main harder pulse at T0+81 to T0+111 sec, and the duration (T90) was about 
96 seconds. The fluences in 100 - 1000 keV were 1.24(-0.16, +0.17) e-6 and 2.89 (-0.08, +0.06) e-5 erg/cm^2 
in the precursor and the main pulse, respectively. The 1-s peak flux measured from T0+94 s
was 7.26 (-0.43, +0.47) photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0+81 s to T0+111 s is well fitted by a power-law with exponential cutoff model:
  dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
  alpha      1.15 (-0.10, +0.09), and
  Epeak      1119 (-135, +137) keV (chi^2/d.o.f. = 79.0/54).

Due to the brightness of this burst, a 3% systematic error
was added for low energy channels.
All the quoted errors are at 90% confidence level.

The light curves of this event are available at the following URL:
 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html

-- 

 Takeshi Uehara  (Hiroshima Univ.)
 E-mail: uehara@hep01.hepl.hiroshima-u.ac.jp


GRB_name: GRB100122A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10354
SUBJECT: GRB 100122A: MASTER-Net  optical observations  
DATE:    10/01/22 16:50:16 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

S.Sergienko, V.Yurkov
Blagoveschensk Educational State University, Blagoveschensk


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

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


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


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


MASTER  robotic telescope (MASTER-Net: http://observ.pereplet.ru, 200
mm, FOV=8 square degrees (testing mode)) and  Very Wide Field Camera (D=50 
mm, 1000 square  degrees, 11 Mpx, 36" per pix, mounted on telescope) 
located at Blagoveschensk   was responted to the  GRB 100122A 
(Fermi-GBM  alert, TRIGGER_NUM: 285864459) 30 sec after first Notice time 
and 59 s after the GRB time . 
We have a number images with exposition from 5s to 180 s.
The image limit from telescope ~17m .
The image limit from Very Wide Filed Camera ~11.5.
Fermi GBM error box locate in   vicinity  Orion Nebula.
More accurate   error-box is required.
The image reduction is continued.

The one of the first nice images MASTER VWF camera (with Orion 
constalation and trees)  is available  at 
http://observ.pereplet.ru/images/GRB100122A/grb.html  .
The message may be cited.

mailto: lipunov@sai.msu.ru


GRB_name: GRB100122A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10355
SUBJECT: GRB 100122A: Fermi GBM detection
DATE:    10/01/23 02:32:50 GMT
FROM:    Narayana Bhat at U Alabama/Huntsville/GBM  <Narayana.Bhat@nasa.gov>

A. von Kienlin (MPE), P. N. Bhat (UAH) and R. D. Preece (UAH)
report on behalf of the Fermi GBM Team:

"At 14:47:37.31 UT on 22 January 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100122A (trigger 285864459 / 100122616).

The on-ground calculated location, using the GBM trigger
data, is RA = 79.2 , DEC = -2.7 (J2000 degrees,
equivalent to 05h 16.8m, -2d 42'), with an uncertainty
of 1.3 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
 
The angle from the Fermi LAT boresight is 45 degrees.

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


The GBM light curve consists of 2 pulses (a weak pulse at trigger followed
by a much larger pulse about 21 s later) with a duration (T90)
of about 6.6 s (8-1000 keV).
The time-averaged spectrum from T0-2.688 s to T0+25.984 s is
adequately fit by a Band function with Epeak = 45.6 +/- 1.5 keV,
alpha = -0.98 +/- 0.05, and beta = -2.31 +/- 0.03

(CSTAT 1673 for 478 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.00 +/- 0.01)E-05 erg/cm^2. The 1.0-sec peak photon flux measured
starting from T0+20.9 s in the 8-1000 keV band
is 10.44 +/- 0.07 ph/s/cm^2.

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


GRB_name: GRB100119A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10356
SUBJECT: Konus-Wind observation of GRB 100119A
DATE:    10/01/23 17:39:23 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 100119A (Swift-BAT trigger=383063:
Mangano et al., GCN 10348) triggered Konus-Wind
at T0=66306.167s UT (18:25:06.167)

The burst light curve shows a complex structure
with a total duration of ~45 s.
The emission is seen up to several MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100119_T66306/

As observed by Konus-Wind the burst
had a fluence of 6.1(+/-0.3)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+18.176s
of 4.3(+/-0.3)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+37.376 s) is well be fitted
in the 20 keV - 10 MeV range by a power law
with GRB (Band) model, for which:
the low-energy photon index alpha = -0.73 (-0.08,+0.09),
the high energy photon index beta = -2.8(-1.9, +0.4),
the peak energy Ep = 377(-35, +35)keV (chi2 = 66/97 dof).

The spectrum of the most intense part of the burst
(measured from T0+15.360 to T0+21.504 s) is well fitted
in the 20 keV - 10 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.52(+/-0.11),
and Ep = 387(-32, +37) keV (chi2 = 97/96 dof).

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


GRB_name: GRB100119A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10357
SUBJECT: GRB 100119A: Suzaku WAM observation of the prompt emission
DATE:    10/01/28 05:12:04 GMT
FROM:    Nicolas Vasquez at Tokyo Inst of Tech  <nvasquez.aa@m.titech.ac.jp>

=========================================================================

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

The long GRB 100119A (Swift BAT trigger #383063; Mangano et al. GCN 10348)
triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an
energy range of 50 keV - 5 MeV at 18:25:09.630 UT (=T0).

The observed light curve shows a complicated structure, with
overlapping pulses. The duration (T90) was about 24 seconds.
The fluence in 100 - 1000 keV band is 4.55(-0.21, +0.17) x 10^-6 erg/cm2
with a 1-s peak flux measured from T0+18.5 sec of 6.94 (-0.63, +0.32)
photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0-3.5 s to T0+37.5 s is well fitted by a cut off power-law model:
 dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
 alpha      1.17 (-0.27, +0.26), and
 Epeak      510 (-45, +54) keV (chi^2/d.o.f. = 26.7/24).

Due to the brightness of this burst, a 3% systematic error
was added for low energy channels.
All the quoted errors are at 90% confidence level.

The light curves of this event are available at the following URL:
 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html

=========================================================================


GRB_name: GRB100131A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10358
SUBJECT: GRB 100131A: Fermi GBM detection
DATE:    10/02/02 06:00:26 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (UAH) reports on behalf of the Fermi GBM Team: 

"At 17:30:57.67 UT on 31 January 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100131A (trigger 286651859 / 100131730).
The Fermi Observatory executed a maneuver following this trigger and 
tracked the burst location for the next 5 hours, subject to 
Earth-angle constraints.

The on-ground calculated location, using the GBM trigger 
data, is RA = 120.4, DEC = +16.5 (J2000 degrees, 
equivalent to 08h 02m, 16d 29'), with an uncertainty 
of 1.2 degrees (radius, 1-sigma containment, 
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight was 27 degrees.

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

The GBM light curve consists of a single bright spike with substructure
with a duration (T90) of about 6.2 s (8-1000 keV). 
The time-averaged spectrum from T0 to T0+4.5 s is 
best fit by a Band function with Epeak = 132.10 +/- 6.28 keV, 
alpha = -0.63 +/- 0.05, and beta = -2.21 +/- 0.05
(Castor C statistic of 413 for 360 d.o.f.).

The event fluence (8-1000 keV) in this time interval is 
(7.723 +/- 0.130)E-06 erg/cm^2. The 0.128-sec peak photon flux measured 
starting from T0 in the 8-1000 keV band is 33.8 +/- 1.5 ph/s/cm^2.

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


GRB_name: GRB100203A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10360
SUBJECT: GRB 100203A Detected in Ground Analysis of BAT Data
DATE:    10/02/04 22:09:23 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>

J. R. Cummings (NASA/GSFC/CRESST), H. A. Krimm (NASA/GSFC/CRESST),
F. E. Marshall (GSFC), D. M. Palmer (LANL)
report on behalf of the Swift-BAT team:

At 18:31:07 UTC on Feb-03-2010, BAT triggered on GRB 100203A.
The source was detected onboard at a significance too low to trigger an 
automated response. In ground analysis, a source was found at RA, Dec = 96.225, 
+4.793, which is

RA (J2000) 06h 24m 54s
Dec (J2000) 4d 47' 33"

with an estimated uncertainty of 2 arcmin radius (90% containment).

The Galactic coordinates of the source are 205.629, -3.690. While the
event appears to be a faint, soft, long GRB,  we cannot completely
discount the possibility of it being a Galactic transient.

The lightcurve shows 3 well-separated peaks, each about 10 seconds long,
at T-50, T+0, and T+60 seconds.

A 4 ksec follow-up observation with the Swift XRT and UVOT has been scheduled.


GRB_name: GRB100205A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10361
SUBJECT: GRB 100205A: Swift detection of a burst
DATE:    10/02/05 04:34:16 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

J. L. Racusin (NASA/GSFC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
D. N. Burrows (PSU), P. A. Evans (U Leicester), E. A. Hoversten (PSU),
J. A. Kennea (PSU), C. B. Markwardt (CRESST/GSFC/UMD),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
D. M. Palmer (LANL), M. H. Siegel (PSU),
M. Stamatikos (OSU/NASA/GSFC), R. L. C. Starling (U Leicester),
T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the
Swift Team:

At 04:18:43 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100205A (trigger=411248).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA 141.406d, Dec  +31.739d,  which is 
   RA(J2000) = 09h 25m 37s
   Dec(J2000) = +31d 44' 22"
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 ~800 counts/sec (15-350 keV), at ~8 sec after the trigger. 

The XRT began observing the field at 04:21:38.0 UT, 174.9 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 141.3874, 31.7405 which
is equivalent to:
   RA(J2000)  = 09h 25m 32.99s
   Dec(J2000) = +31d 44' 25.8"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 57 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
1.65e+20 cm^-2 (Kalberla et al. 2005). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 177 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. 

Burst Advocate for this burst is J. L. Racusin (judith.racusin 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: GRB100205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10362
SUBJECT: GRB 100205A: NOT optical observations
DATE:    10/02/05 06:01:21 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

D. Malesani (DARK/NBI), D. Xu (WIS and DARK/NBI), J. P. U. Fynbo 
(DARK/NBI), P. Jakobsson (Univ. Iceland), N. R. Tanvir (Univ. 
Leicester), J. Lindberg (NOT and Univ. Copenhagen), report on behalf of 
a larger collaboration:

We observed the field of GRB 100205A (Racusin et al., GCN 10361) with 
the NOT equipped with ALFOSC. Observations were carried out in the R and 
I bands, starting at 4:58 and 5:16 UT, that is 39 and 58 min after the 
GRB, respectively.

Within the XRT error circle, we do not detect any new source down to 
limiting magnitudes R > 23.7 and I > 23.2 (assuming R=17.3 and I = 16.8 
for the object at RA = 09:25:28.94, Dec = +31:44:20.8).

We encourage NIR observations.


GRB_name: GRB100131A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10363
SUBJECT: GRB 100131A: Suzaku WAM observation of the prompt emission
DATE:    10/02/05 06:03:29 GMT
FROM:    Yusuke Nishioka at Miyazaki U.  <yusuke613@astro.miyazaki-u.ac.jp>

 Y. Nishioka, H. Hayashi, N. Ohmori, A. Daikyuji, E. Sonoda, K. Kono,
 K. Noda, M. Yamauchi (Univ. of Miyazaki), T. Sugasahara, M. Tashiro, 
 Y. Terada, A. Endo, K. Onda, W. Iwakiri (Saitama U.), S. Sugita
 (Nagoya U.), K. Yamaoka (Aoyama  Gakuin U.), M. Ohno, M. Suzuki, 
 M. Kokubun, T. Takahashi (ISAS/JAXA), Y. E. Nakagawa, T. Tamagawa 
 (RIKEN), N. Vasquez (Tokyo Tech.), Y. Urata, H.M  Lin (NCU), 
 Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.), 
 T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), S. Hong (Nihon U.), 
 on behalf of the Suzaku WAM team, report
 
 The long GRB 100131A (Fermi/GBM trigger #286651859 ; A. Goldstein et al., GCN 10358) 
 triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers an 
 energy range of 50 keV - 5 MeV on 2010-01-31 17:30:58.052 UT (=T0). 
 
 The observed light curve shows a multi-peaked structure lasting from T0-0.5s to T0+2s,
 followed by a weaker emission seen up to T0+4s with a duration (T90) of 
 about 3.2 seconds. The fluence in 100 - 1000 keV was 2.72(-0.41, +0.30) x10^-6 erg/cm^2. 
 The 1-s peak flux measured from T0 s was 4.52(-0.80, +0.57) photons/cm^2/s in the same 
 energy range.

 Preliminary result shows that the time-averaged spectrum from T0-0.5s to 
 T0+5.5s is well fitted by a single power-law with a photon index 
 of 2.62 (-0.37, +0.44) (chi^2/d.o.f = 11.8/13).

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

 The light curves for this burst are available at:

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


GRB_name: GRB100205A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10364
SUBJECT: GRB 100205A: Super-LOTIS early observations
DATE:    10/02/05 06:20:25 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

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

We observed the field of GRB 100205A (Racusin et al., GCN 10361) with the
0.6m Super-LOTIS telescope located at KPNO under poor conditions.
Observations began 110 seconds after the trigger and continued for 7
minutes before we were forced to close due to humidity.  In 270 seconds of
stacked V-band exposures, we detect no new sources in the XRT error circle
down to a limiting magnitude V > 18 (upon comparison to the NOMAD
catalog), which is consistent with the NOT observations (Malesani et al.,
GCN 10362).


GRB_name: GRB100205A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10365
SUBJECT: GRB 100205A: Gemini-South Observations
DATE:    10/02/05 08:13:43 GMT
FROM:    Bethany Cobb at UC Berkeley  <bcobb@astro.berkeley.edu>

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

We have imaged the field of GRB 100205A (Racusin et al., GCN 10361) with
the Gemini Multi-Object Spectrograph (GMOS) on the 8 m Gemini South
telescope beginning at 05:48 UT on 05 February 2010 (~ 40 minutes after
the burst trigger time).  Observations were conducted in the r' filter for
a total of 600 seconds.

We find no new point sources at the location of the X-ray afterglow 
(Racusin et al., GCN 10361).  The preliminary limiting magnitude of our
image is r' >~ 23.4 mag for isolated point sources (assuming the SDSS
value of r = 17.76 for the object at RA: 09:25:28.956, Dec: +31:44:20.61).


GRB_name: GRB100205A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10366
SUBJECT: GRB 100205A Gemini-North IR afterglow candidate
DATE:    10/02/05 12:24:45 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick), 
A. Cucchiara & D. Fox (PSU), B. E. Cobb (UC Berkeley),
R. Mason (Gemini) report on behalf of a larger collaboration:

We observed the field of GRB 100205A (Racusin et al. GCN 10361)
with Gemini-North/NIRI, beginning at 06:55 UT (approx 2.6 hr post burst).

In a deep K-band integration we detect a point source within
the enhanced XRT error circle, at position (accuracy ~0.5 arcsec):

RA(2000) = 09 25 33.02
dec(2000)= +31 44 25.0

The approximate magnitude (calibrated against two faint 2MASS stars
in the field) is K~20.2.  The source is also marginally detected
in both J and H.

Further analysis is ongoing.


GRB_name: GRB100205A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10367
SUBJECT: GRB 100205A: Enhanced Swift-XRT position
DATE:    10/02/05 14:00:10 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

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

Using 1394 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 100205A, 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 = 141.38751, +31.74050 which is equivalent
to:

RA (J2000): 09h 25m 33.00s
Dec (J2000): +31d 44' 25.8"

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: GRB100203A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10368
SUBJECT: GRB 100203A: Swift XRT and UVOT refined analyses
DATE:    10/02/05 16:44:31 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C. Starling (U Leicester), E.A. Hoversten (PSU) and F.E.
Marshall (NASA/GSFC) report on behalf of the Swift XRT and 
UVOT teams:

We observed the Swift GRB 100203A, detected in ground analysis 
(Cummings et al. GCN Circ. 10360), with Swift XRT and UVOT 
beginning 25.66 hours (92.3 ks) after the BAT trigger (#411011). 

The XRT observed the field for 3.85 ks. No source has been detected at 
the 3-sigma confidence level or above, with a 3-sigma upper limit on the 
count rate at the BAT position of 6 x 10^-3 ct s^-1. We note that this 
source lies near the Galactic Plane, where Galactic absorption in this 
direction is high, at 5.3 x 10^21 cm^-2.

The UVOT observed the field of GRB 100203A in the uvm2 filter.
Visual comparison with DSS images of the field reveal no afterglow
candidates. Given the low Galactic latitude, afterglow detection
is complicated by high extinction and numerous bright stars in the
field.

The observed 3-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for initial exposures are:

Filter   T_start(s)   T_stop(s)   Exp(s)   3-sigma upper limit
=============================================================
uvm2       92604       103268      3915         > 21.27

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.55 in the direction of the burst
(Schlegel et al. 1998).

This circular is an official product of the Swift team.


GRB_name: GRB100205A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  10369
SUBJECT: GRB 100205A: Swift XRT refined analysis
DATE:    10/02/05 16:47:28 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C. Starling (U Leicester) and J.L. Racusin (NASA/GSFC) report on 
behalf of the Swift-XRT team:

We have analysed 1.5 ks of XRT data for GRB 100205A 
(trigger=411248, Racusin et al. GCN Circ. 10361), from 157 s to 4.95 ks 
after the BAT trigger. The data comprise 11 s of Windowed Timing (WT)
mode settling data and the remainder is in Photon Counting (PC) mode. 
At this point Swift coverage of the source stopped due to thermal 
constraints, but further observations are now underway. 
The enhanced XRT position is given in Evans et al. GCN Circ. 10367.

The light curve can be fit with a doubly broken power law. The difference 
between the initial WT mode settling data and the first PC data suggest 
a steep initial decay of alpha~9.5. This power law decay breaks at ~180 s 
to a plateau with alpha~-0.05, which breaks at 330 +140/-60 s to a decay 
of alpha = 2.5 +0.4/-0.3.

The time-averaged PC mode spectrum can be fit with an absorbed power law 
of photon index Gamma = 2.2 +/-0.3, and absorption column
N_H (intrinsic at z=0) = (7 +6/-5) x 10^20 cm^-2 in excess of the Galactic 
column of 1.65 x 10^20 cm^-2 (Kalberla et al. 2005). 
The observed (unabsorbed) 0.3-10 keV flux is (9.0 +1.6/-2.0) x 10^-12 (1.2 
x 10^-11) erg cm^-2 s^-1.
The observed (unabsorbed) counts to flux conversion is 3.7 x 10^-11 (4.9 x 
10^-11) erg cm^-2 ct^-1.

If the light curve continues to decay with alpha = 2.5 the predicted count 
rate at T+24h is 1 x 10^-6 ct s^-1.

The results of the XRT-team automatic analysis are available at 
http://www.swift.ac.uk/xrt_products/00411248.

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


