TITLE:   GCN CIRCULAR
NUMBER:  28512
SUBJECT: GRB 200925B: Swift-XRT refined analysis update
DATE:    20/09/27 11:32:20 GMT
FROM:    Andy Beardmore at U Leicester  <ab271@leicester.ac.uk>

A.P. Beardmore (U. Leicester) and S. B. Cenko (GSFC) report on
behalf of the Swift-XRT team:

An additional 4.9 ks of Swift-XRT Photon Counting mode data have
been collected on GRB 200925B (Cenko et al.  GCN Circ. 28499,
Sbarufatti et al. GCN Circ. 28508), bringing the total XRT
exposure to 10 ks, from 87 s to 86.3 ks after the BAT trigger.
The late time X-ray light curve from T0+29.2 ks to 86.3 ks
is now decaying with a power-law decay slope of 1.1 +/- 0.4.

If the light curve continues to decay at the same rate than
the predicted count rate at T0+3 days will be 3.4e-03 count/sec,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 
1.05 x 10^-13 (1.28 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00997453.

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