TITLE: GCN CIRCULAR NUMBER: 35345 SUBJECT: GRB 231215A: Swift-XRT observations DATE: 23/12/15 11:15:35 GMT FROM: Phil Evans at U of Leicester <pae9@star.le.ac.uk> P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU), S. Campana (INAF-OAB) and G. Cusumano (INAF-IASF PA) report on behalf of the Swift-XRT team: The XRT began observing the field of GRB 231215A at 10:32:51.0 UT, 2725.7 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 9.74175, 57.64645 which is equivalent to: RA(J2000) = 00h 38m 58.02s Dec(J2000) = +57d 38' 47.2" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 22 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 https://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 (4.25 x 10^21 cm^-2, Willingale et al. 2013), with an excess column of 4.7 (+2.34/-2.12) x 10^21 cm^-2 (90% confidence). View this GCN Circular online at https://gcn.nasa.gov/circulars/35345. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...