TITLE: GCN CIRCULAR NUMBER: 35852 SUBJECT: GRB 240215A: Swift-XRT afterglow detection DATE: 24/03/03 16:24:26 GMT FROM: Phil Evans at U of Leicester D.N. Burrows (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), C. Salvaggio (INAF-OAB), M. Ferro (INAF-OAB), R. Brivio (INAF-OAB), J. D. Gropp (PSU), S. Dichiara (PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Swift/BAT-detected burst GRB 240215A in a series of observations tiled on the sky. The total exposure time is 4.4 ks, distributed over 4 tiles; the maximum exposure at a single sky location was 2.7 ks. The data were collected between T0+44.5 ks and T0+1384.7 ks, and are entirely in Photon Counting (PC) mode. Four uncatalogued X-ray sources are detected, of which one ("Source 2") is fading with >3-sigma significance, and is therefore likely the GRB afterglow. The position of this source is RA, Dec=132.0101, -6.5099 which is equivalent to: RA (J2000): 08:48:2.42 Dec(J2000): -06:30:35.5 with an uncertainty of 8.1 arcsec (radius, 90% confidence). This position is 14.9 arcmin from the Swift/BAT position. The source is fading with alpha >0.5. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00021670. The results of the full analysis of the tiled XRT observations are available at https://www.swift.ac.uk/xrt_products/TILED_GRB00123. This circular is an official product of the Swift-XRT team.