[vsnet-grb-info 16762] GRB 150722A: Swift-XRT observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18043
SUBJECT: GRB 150722A: Swift-XRT observations
DATE:    15/07/22 12:06:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9 at leicester.ac.uk>

S. Campana (INAF-OAB), P.A. Evans (U. Leicester), J.P. Osborne (U.
Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU) and G. Tagliaferri
(INAF-OAB) report on behalf of the Swift-XRT team:

The XRT began observing the field of GRB 150722A at 10:51:48.0 UT,
3234.9 seconds after the BAT trigger. Using promptly downlinked data we
find a fading, uncatalogued X-ray source located at RA, Dec 218.27775,
-35.19644 which is equivalent to:
   RA(J2000)  = 14h 33m 06.66s
   Dec(J2000) = -35d 11' 47.2"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 17 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 5.92
x 10^20 cm^-2 (Willingale et al. 2013).