GCN Circular 4019
Subject
GRB 050922B: Swift-BAT refined analysis
Date
2005-09-23T00:03:15Z (19 years ago)
From
Takanori Sakamoto at NASA/GSFC <takanori@milkyway.gsfc.nasa.gov>
D. Hullinger (UMD), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/NRC), E. Fenimore (LANL), F. Marshall (GSFC),
N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC),
G. Sato (ISAS), A. Smale (NASA HQ), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Using the data set from T-120 to T+450 sec from the recent telemetry
downlink, we report further analysis of Swift-BAT GRB 050922B
(trigger #156434) (Norris, et al., GCN 4008). The refined BAT ground
position is (RA,Dec) = 5.789, -5.602 {00:23:09,-05:36:08} [deg; J2000]
+-2.3 arcmin, (radius, sys+stat, 90% containment). The partial coding
was 12%.
The light curve shows a broad peak from T+15 to T+65 and a second peak
from T+80 to T+110. There is no extended emission T>120 sec.
T90 (15-350 keV) is (80 +- 10) sec (estimated error including systematics).
The power law index of the time-averaged spectrum is 1.89 +- 0.23.
The fluence in the 15-150 keV band is (1.8 +- 0.3) x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T0+98 sec in the 15-150 keV
band is (1.1 +- 0.4) ph/cm2/sec. All the quoted errors are at the 90%
confidence level.