GCN Circular 17981
Subject
GRB 150626B, Swift-BAT refined analysis
Date
2015-06-28T20:03:41Z (9 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
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),
L. M. McCauley (PSU), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 150626B (trigger #646786)
(McCauley et al., GCN Circ. 17966). The BAT ground-calculated position is
RA, Dec = 187.627, 66.794 deg which is
RA(J2000) = 12h 30m 30.6s
Dec(J2000) = +66d 47' 39.6"
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 35%.
The mask-weighted light curve shows a single-peaked structure that starts
at ~T-15 s, peaks at ~T+1 s, and ends at ~T+30 s. T90 (15-350 keV)
is 48.0 +- 22.6 sec (estimated error including systematics).
The time-averaged spectrum from T-15.6 to T+32.4 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.36 +- 0.21. The fluence in the 15-150 keV band is 1.0 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+7.94 sec in the 15-150 keV band
is 0.6 +- 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/646786/BA/