GCN Circular 8054
Subject
GRB 080802: Swift-XRT Refined Analysis
Date
2008-08-03T03:20:34Z (16 years ago)
From
Michael Stroh at PSU/Swift <stroh@astroh.org>
M.C. Stroh (PSU) reports on behalf of the Swift-XRT team:
We have analyzed the first two orbits of Swift-XRT data obtained for
GRB 080802 (Baumgartner et al., GCN Circ. 8051), totaling 81s of
Windowed Timing and 2.4ks of Photon Counting data.
The X-ray light-curve begins with a single flare that peaks to ~40 cts/
s near T+100 seconds. The rest of the light-curve can be fit by a
single broken power-law with an initial decay index of 2.91 +/- 0.33,
second decay index of -0.51 +/- 0.25 and a break near T+1000s. Since
the second decay index indicates brightening, we cannot accurately
predict counting rates at T+24 or T+48 hours.
The spectrum from the Windowed Timing data can be fit with a power-law
in excess of the Galactic value (2.75e21 cm-2, Kalberla et al. 2005),
with a column density of 4.8 (+2.0/-1.7)e21 cm^-2 and a photon index
of 1.40 (+0.24/-0.22). The observed (unabsorbed) 0.3-10 keV flux is
4.78e-10 (4.95e-10) ergs/cm^2/s.
This is an official product of the Swift-XRT team.