GCN Circular 20597
Subject
GRB 170203A: Swift-BAT refined analysis
Date
2017-02-03T17:29:04Z (7 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
J. R. Cummings (CPI), S. D. Barthelmy (GSFC), N. Gehrels (GSFC),
H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC), 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+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 170203A (trigger #736432)
(Racusin, et al., GCN Circ. 20583). The BAT ground-calculated position is
RA, Dec = 332.861, 25.186 deg which is
RA(J2000) = 22h 11m 26.6s
Dec(J2000) = +25d 11' 08.4"
with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 67%.
The mask-weighted light curve shows a single main peak, which starts at T+0 sec,
peaks at T+5 sec and decays to background by T+30 sec. There is a much
weaker peak from T+25 to T+50 sec. T90 (15-350 keV) is 45.2 +- 6.4 sec
(estimated error including systematics).
The time-averaged spectrum from T-0.04 to T+48.43 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.53 +- 0.29. The fluence in the 15-150 keV band is 6.2 +- 1.1 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+3.70 sec in the 15-150 keV band
is 0.8 +- 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/736432/BA/