GCN Circular 13414
Subject
GRB 120703A: Swift-BAT refined analysis
Date
2012-07-04T13:10:16Z (12 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
M. Stamatikos (OSU), 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), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), J. Tueller (GSFC),
T. N. Ukwatta (MSU), B.-B. Zhang (PSU) (i.e. the Swift-BAT team):
Using the data set from T-61 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 120703A (trigger #525671)
(Zhang, et al., GCN Circ. 13408). The BAT ground-calculated position is
RA, Dec = 339.353, -29.726 deg, which is
RA(J2000) = 22h 37m 24.7s
Dec(J2000) = -29d 43' 34.9"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%.
The mask-weighted light curve shows the burst started at ~T-45 sec with a weak
pulse with a width of about 20 sec. The burst continues with a moderate increase
to a strong central pulse from T-0.2 to T+1.0 sec, and then a decay back
to baseline at ~T+45 sec. T90 (15-350 keV) is 25.2 +- 4.3 sec
(estimated error including systematics).
The time-averaged spectrum from T-7.27 to T+32.60 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.51 +- 0.06. The fluence in the 15-150 keV band is 3.5 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.06 sec in the 15-150 keV band
is 10.5 +- 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/525671/BA/