[vsnet-grb-info 6923] GRB 081024B: Swift-XRT late-time observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8513
SUBJECT: GRB 081024B: Swift-XRT late-time observations
DATE:    08/11/10 16:01:33 GMT
FROM:    Cristiano Guidorzi at INAF-OAB  <cristiano.guidorzi at brera.inaf.it>

C. Guidorzi (INAF-OAB) on behalf of the Swift-XRT team reports:

Swift-XRT re-observed the field of the Fermi-LAT and Fermi-GBM
GRB 081024B (Omodei et al. GCN Circ. 8407; Connaughton et al GCN Circ. 8408)
from 13.1 to 15.1 days after the burst with a net exposure of 9.8 ks.

We compared this with our previous observations (Guidorzi et al. GCN Circ.
8410, 8416, 8454). We still detect source 2, identified in our first
observation (Guidorzi et al. GCN Circ. 8410), with a count rate of
(1.1 +- 0.4)e-3 count/s, which is compatible with a constant rate
source throughout the entire XRT observations.
We also derived an upper limit to the possible power-law decay
index of alpha<0.4 from ~1e5 to ~1.3e6 s (90% confidence).
We conclude that source 2, initially proposed as possibly associated
with GRB 081024B (Guidorzi et al. GCN Circ. 8416, 8454), is not the
corresponding X-ray afterglow.

This circular is an official product of the Swift-XRT team.