GCN Circular 13040
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 120311B at 15:59:18.5 UT, 3067.7 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 258.56101, -13.05235 which is equivalent to: RA(J2000) = 17h 14m 14.64s Dec(J2000) = -13d 03' 08.5" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 212 arcseconds from the BAT onboard position. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. This position is more than 2-sigma away from the BAT position, and so possibly unrelated to the trigger. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 1.64 x 10^21 cm^-2 (Kalberla et al. 2005).