GCN Circular 7806
Subject
GRB 080603B, Swift-BAT refined analysis
Date
2008-06-04T12:32:40Z (17 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), V. Mangano (INAF-IASFPA), C. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. Palmer (LANL), A. M. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+470 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080603B (trigger #313087)
(Mongano, et al., GCN Circ. 7794). The BAT ground-calculated position is
RA, Dec = 176.554, 68.061 deg, which is
RA(J2000) = 11h 46m 13.0s
Dec(J2000) = +68d 03' 40.5"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows three main clusters of peaks. The first
starts at T-1 sec, peaks at T+1 sec, and ends at ~T+7 sec. The second
starts at T+8 sec and ends at T+20 sec. The third starts at ~T+42 sec
and ends at ~T+80 sec. T90 (15-350 keV) is 60 +- 4 sec (estimated error
including systematics).
The time-averaged spectrum from T-0.1 to T+68.6 sec is best fit by a power law
with an exponential cutoff. This fit gives a photon index 1.21 +- 0.30,
and Epeak of 71.0 +- 16.0 keV (chi squared 63.16 for 56 d.o.f.). For this
model the total fluence in the 15-150 keV band is 2.4 +- 0.1 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+0.96 sec in the 15-150 keV band is
3.5 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index
of 1.78 +- 0.07 (chi squared 75.18 for 57 d.o.f.). 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/313087/BA/