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GCN Circular 12602

Subject

GRB 111129A: Swift-BAT refined analysis

Date

2011-11-30T00:47:25Z (12 years ago)

From

Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC), T. Sakamoto (GSFC/UMBC),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-61 to T+242 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 111129A (trigger #508712)
(Racusin, et al., GCN Circ. 12600Not found
 
 
).  The BAT ground-calculated position is
RA, Dec = 307.415, -52.722 deg, which is 
   RA(J2000)  =  20h 29m 39.5s 
   Dec(J2000) = -52d 43' 20.9" 
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 61%.
 
The mask-weighted light curve shows two slightly overlapping peaks
starting at ~T-7 sec, peaking at ~T-5 and T+1 sec, and ending at ~T+10 sec.
T90 (15-350 keV) is 7.6 +- 1.4 sec (estimated error including systematics).
 
The time-averaged spectrum from T-6.29 to T+2.88 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.56 +- 0.38.  The fluence in the 15-150 keV band is 1.8 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.41 sec in the 15-150 keV band
is 0.9 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/508712/BA/