GCN Circular 4135
Subject
GRB 051021B: Refined analysis of the Swift-BAT burst
Date
2005-10-22T15:52:56Z (19 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
S. Barthelmy (GSFC), L. Barbier (GSFC), P. Boyd (GSFC-UMBC),
J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (GSFC/UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC),
G. Sato (ISAS), J. Tueller (GSFC), W. Voges (MPE)
on behalf of the Swift-BAT team:
Using the full data set from the recent telemetry downlink, we report
further analysis of Swift-BAT GRB 051021B (trigger #160672)
(Retter, et al., GCN 4126). The ground-analysis position is
RA,Dec 126.059,-45.537 {8h 24m 14.2s,-45d 32' 13.0"} (J2000)
with an uncertainty of 1.3 arcmin (radius, 90%, stat+sys).
T90 is 47 +- 3 sec. The partial coding fraction is 88 %.
The lightcurve has single FRED peak starting at T-6 sec (FWHM of ~12 sec)
with the decay extending out to greater than T+20 sec. There is
a second, smaller peak at ~T+20. Fitting a simple power law over
the full interval from T-5.5 to T+51.5 sec, the photon index is
1.52 +/- 0.14 with a fluence of 9.1 +/- 0.8 X 10^-7 erg/cm^2.
The peak flux in a 1-sec wide window starting at T-2.5 sec
is 0.63 +/- 0.13 ph/cm^2/sec. All values are in the 15-150 keV band
at the 90% confidence level.