GCN Circular 6580
Subject
INTEGRAL burst GRB070615: X-ray continued observations
Date
2007-06-26T15:01:42Z (17 years ago)
From
Olivier Godet at U.of Leicester <og19@star.le.ac.uk>
O. Godet, N. Lyons, K.L. Page, A.P. Beardmore (U. Leicester) report on
behalf the Swift-XRT team:
In Godet et al. (GCN Circ. 6544), we reported the detection of a faint
and uncatalogued X-ray source after analysing 3ks of Swift PC data taken
10.7h after the IBAS trigger (Mereghetti et al., GCN Circ. 6537). We
estimated the source count rate to be between 5.5e-4 c/s and 3.6e-3 c/s
at a 95% confidence level using the Bayesian method. However, it was
impossible to say whether or not the source was fading due to the limited
statistics.
We analysed 8.5ks of additional PC data taken 6.9 days after the IBAS
trigger and no counts were found inside the 7.5 arcsec radius error
circle. In this region, only 0.1 background counts would be expected.
Using the Bayesian method, we estimated the upper limit on the count
rate to be around 3.5e-4 c/s at a 95% confidence level.
So, the weak X-ray source may be fading.
This is an official product of the Swift XRT team.