[vsnet-grb-info 16154] GRB 150211A: Swift-XRT observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17435
SUBJECT: GRB 150211A: Swift-XRT observations
DATE:    15/02/11 12:54:45 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 150211A at 12:27:22.5 UT,
2111.0 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source located at RA, Dec 254.85863,
55.39235 which is equivalent to:
   RA(J2000)  = 16h 59m 26.07s
   Dec(J2000) = +55d 23' 32.5"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 34 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 in excess of the Galactic value (1.61 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 5.1
(+2.58/-2.25) x 10^21 cm^-2 (90% confidence).