[vsnet-grb-info 14636] GRB 140311B: Swift-XRT observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15950
SUBJECT: GRB 140311B: Swift-XRT observations
DATE:    14/03/11 23:07:34 GMT
FROM:    Phil Evans at U of Leicester  <pae9 at leicester.ac.uk>

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

The XRT began observing the field of GRB 140311B at 22:11:04.3 UT,
3394.7 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source located at RA, Dec 252.32458,
52.72393 which is equivalent to:
   RA(J2000)  = 16h 49m 17.90s
   Dec(J2000) = +52d 43' 26.1"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 110 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 3.03
x 10^20 cm^-2 (Kalberla et al. 2005).