TITLE: GCN CIRCULAR NUMBER: 18640 SUBJECT: GRB 151122A: Swift-XRT observations DATE: 15/11/24 08:56:56 GMT FROM: Phil Evans at U of Leicester A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), D.N. Burrows (PSU), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Swift/BAT-detected burst GRB 151122A (David Palmer et al. GCN Circ. 18637), collecting 3.0 ks of Photon Counting (PC) mode data between T0+102.9 ks and T0+114.0 ks. Two uncatalogued X-ray sources have been detected inside or close to the Swift/BAT error region, however none of them is above the RASS limit or shows definitive signs of fading. Therefore, at the present time we cannot identify which, if any, is the afterglow. Details of these sources are given below: Source 1: RA (J2000.0): 299.6973 = 19:58:47.35 Dec (J2000.0): -19.9063 = -19:54:22.8 Error: 4.7 arcsec (radius, 90% conf.) Count-rate: 0.0100 ± 0.0023 ct s^-1 Flux: (4.24 ± 0.95)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) This source is 5.8" away from PMN J1958-1954, classified in SIMBAD as a radio source. Source 2: RA (J2000.0): 299.6668 = 19:58:40.03 Dec (J2000.0): -19.9360 = -19:56:09.5 Error: 4.9 arcsec (radius, 90% conf.) Count-rate: (3.9 ± 1.6)e-3 ct s^-1 Flux: (1.57 ± 0.64)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) This source is 2.1" from HD 189004, a high proper-motion, K star. Another uncatalogued was also detected, however this was too far from the GRB position to be the afterglow. The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/ToO_GRBs/00020560. This circular is an official product of the Swift-XRT team.