[vsnet-grb-info 12371] GRB 120911A: Swift-XRT observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13746
SUBJECT: GRB 120911A: Swift-XRT observations
DATE:    12/09/11 09:07:47 GMT
FROM:    Phil Evans at U of Leicester  <pae9 at star.le.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 120911A at 08:04:07.0 UT,
3333.2 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source located at RA, Dec 357.98152,
63.09831 which is equivalent to:
   RA(J2000)  = 23h 51m 55.56s
   Dec(J2000) = +63d 05' 53.9"
with an uncertainty of 4.4 arcseconds (radius, 90% containment). This
location is 33 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.  We
cannot determine whether the source is fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 6.66
x 10^21 cm^-2 (Kalberla et al. 2005).