GCN Circular 8087
Subject
GRB 080810: Swift-XRT Team refined analysis
Event
Date
2008-08-10T23:53:16Z (18 years ago)
From
Kim Page at U.of Leicester <kpa@star.le.ac.uk>
K.L. Page (U. Leicester) reports on behalf of the Swift-XRT team:
We have analysed the first four orbits of the XRT data obtained for GRB
080810 (Page et al., GCN Circ. 8080). The first orbit (376 s) was taken
entirely in Windowed Timing (WT) mode, followed by 2.8 of Photon Counting
(PC) data. The UVOT-enhanced position was given by Evans et al. in GCN
Circ. 8086.
The WT data show a number of flares, with the strongest peaking around 107
and 209 s after the trigger; the first of these is also visible in the BAT
data. The PC data in later orbits can be modelled with a single power-law
decay, with alpha = 1.20 +0.12/-0.11.
There is strong spectral evolution throughout the first orbit, as is
typical for flaring activity. A spectrum extracted from the PC mode data
(3.8-12.1 ks after the trigger) can be fitted with a power-law of Gamma =
1.98 +/- 0.06, absorbed by the Galactic column in this direction of
3.28x10^20 cm^-2. The observed (unabsorbed) flux over this time is 1.99
(2.20) x 10^-11 erg cm^-2 s^-1.
If the decay continues with alpha = 1.2, the predicted count-rate at 24
hours is 0.02 count s^-1, corresponding to an observed (unabsorbed) flux
of 8.5 (9.4) x 10^-13 erg cm^-2 s^-1.
This is an official product of the Swift-XRT team.