GCN Circular 4020
Subject
GRB 050922C: Swift-BAT refined analysis
Date
2005-09-23T00:37:09Z (19 years ago)
From
Takanori Sakamoto at NASA/GSFC <takanori@milkyway.gsfc.nasa.gov>
H. Krimm (GSFC/USRA), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cannizzo (GSFC-UMBC), L. Cominsky (Sonoma State U.),
J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (UMD), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), G. Sato (ISAS),
J. Tueller (GSFC) on behalf of the Swift-BAT team:
Using the data set from T-10 to T+60 sec from the recent telemetry
downlink, we report further analysis of Swift-BAT GRB 050922C
(trigger #156467) (Norris, et al., GCN 4013). The refined BAT ground position
is (RA,Dec) = 317.381, -8.762 {21:09:32, -8:45:43} [deg; J2000]
+- 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding
was 53%.
The light curve shows the intense broad peak starting from T-3 to T+3 with
at least two sub-peaks on top. T90 (15-350 keV) is (5 +- 1) sec
(estimated error including systematics).
The power law index of the time-averaged spectrum is 1.33 +- 0.06.
The fluence in the 15-150 keV band is (1.7 +- 0.1) x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.02 sec in the 15-150 keV
band is (7.5 +- 0.3) ph/cm2/sec. All the quoted errors are at the 90%
confidence level.