Skip to main content
New! Circulars over Kafka, Heartbeat Topic, and Schema v4.1.0. See news and announcements

GCN Circular 7981

Subject
GRB 080714: Swift-XRT refined analysis
Date
2008-07-15T14:04:07Z (16 years ago)
From
Giulia Stratta at ASDC <giulia.stratta@gmail.com>
G. Stratta, M. Perri, B. Preger (ASDC) report on behalf of the
Swift-XRT team:

We analysed the first 3 orbits of XRT data for GRB 080714 (Perri et al.,
GCN Circ. 7978) taken from 88s after the trigger (T0) in Windowed Timing
(WT)
mode and then in Photon Counting (PC) mode from T0+233 s to T0+9874 s.
The UVOT-enhanced XRT position was given by Goad et al. (GCN Circ. 7980).

The X-ray light curve from T0+88s up to ~T0+300s shows an initial 40 seconds
long flat segment followed by an increasingly steepening decay. Starting
from
T0+300s (PC data) the light curve can be fit with a power law model with a
best fit slope of 1.0+/-0.1.

The WT data spectrum from T0+88s to T0+231s is well fitted by an absorbed
power law model with photon index Gamma=1.14+/-0.05 and a total equivalent
hydrogen column density of NH=(0.3+/-0.1)e22 cm**-2. The Galactic NH is
5.44e21 cm**-2 (Kalberla et al. 2005). The 0.3-10 keV observed (unabsorbed)
flux is (3.4+/-0.2)e-10 erg/cm**2/s ((3.9+/-0.2)e-10 erg/cm**2/s).

If the light-curve continues to decay with the same rate, the count rate
24 hours after the trigger is estimated to be ~6e-3 counts/s, which
corresponds to an observed flux of ~5e-13 erg/cm**2/s.

This is an official product of the Swift-XRT team.
Looking for U.S. government information and services? Visit USA.gov