GCN Circular 7498
Subject
GRB 080319D, Swift-BAT refined analysis
Date
2008-03-21T13:15:13Z (16 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
T. Ukwatta (GWU) S. D. Barthelmy (GSFC), P. J. Brown (PSU),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080319D (trigger #306793)
(Brown, et al., GCN Circ. 7453). The BAT ground-calculated position is
RA, Dec = 99.479, 23.982 deg which is
RA(J2000) = 06h 37m 55.0s
Dec(J2000) = +23d 58' 56.0"
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 59%.
The mask-weighted light curve shows a roughly symmetric peak starting
at ~T+0, peaking at ~T+23, and ending at ~T+50 sec.
T90 (15-350 keV) is 24 +- 4 sec (estimated error including systematics).
The time-averaged spectrum from T+5.0 to T+34.5 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.92 +- 0.35. The fluence in the 15-150 keV band is 3.2 +- 0.7 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+25.35 sec in the 15-150 keV band
is 0.1 +- 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/306793/BA/