GCN Circular 3305
Subject
GRB 050421: Swift-BAT refined analysis
Date
2005-04-21T15:44:53Z (20 years ago)
From
Louis M Barbier at NASA/GSFC/Swift <lmb@cosmicra.gsfc.nasa.gov>
T. Sakamoto (GSFC/NRC), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
T. Mitani (ISAS), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC),
G. Sato (ISAS), M. Suzuki (Saitama), J. Tueller (GSFC),
on behalf of the Swift/BAT team:
At 04:11:52 UT Swift-BAT detected GRB 050421 (trigger=115135)
(GCN Circ 3296, Barbier et al.). The refined BAT ground position
is (RA,Dec) = 307.306, +73.665, [deg; J2000] +- 3.4 arcmin, (95%
containment). The partial coding was 91%.
The light curve has a FRED structure with a rise in < 1 second and a decay
in ~10 seconds. T90 (15-350 keV) is (10.3 +- 2) seconds
(estimated error including systematics).
The photon index of the time-averaged spectrum is 1.7 +-0.4.
The fluence in the 15-350 keV band is (1.8 +- 0.7 ) x 10^-7 erg/cm2.
The 1-s peak photon flux measured from T0+1.4 seconds in the 15-350
keV band and is (0.5 +- 0.1) ph/cm2/s. All the quoted errors are at the 90%
confidence level.