GCN Circular 18091
Subject
GRB 150728A: Swift-BAT refined analysis
Date
2015-07-28T17:30:34Z (9 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU)
(i.e. the Swift-BAT team):
Using the data set from T-240 to T+946 sec from the recent telemetry downlinks,
we report further analysis of BAT GRB 150728A (trigger #650617)
(Krimm, et al., GCN Circ. 18087). The BAT ground-calculated position is
RA, Dec = 292.271, 33.906 deg, which is
RA(J2000) = 19h 29m 05.1s
Dec(J2000) = +33d 54' 20.8"
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows a single spike starting at ~T_zero
and ending at ~T+1.5 sec. T90 (15-350 keV) is 0.83 +- 0.23 sec
(estimated error including systematics).
The time-averaged spectrum from T+0.24 to T+1.20 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
2.02 +- 0.48. The fluence in the 15-150 keV band is 3.3 +- 1.0 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T+0.22 sec in the 15-150 keV band
is 0.5 +- 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/650617/BA/