TITLE: GCN CIRCULAR NUMBER: 35234 SUBJECT: GRB 231129C: Swift-XRT observations DATE: 23/11/30 13:59:14 GMT FROM: Phil Evans at U of Leicester J. D. Gropp (PSU), S. Dichiara (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J.A. Kennea (PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Fermi/GBM-detected burst GRB 231129C in a series of observations tiled on the sky. The total exposure time is 1.5 ks, distributed over 4 tiles; the maximum exposure at a single sky location was 633 s. The data were collected between T0+19.3 ks and T0+35.4 ks, and are entirely in Photon Counting (PC) mode. One uncatalogued X-ray source has been detected, it is below the RASS limit and shows no definitive signs of fading. Therefore, at the present time we cannot confirm this as the afterglow. Details of this source are given below: Source 2: RA (J2000.0): 11.1769 = 00:44:42.45 Dec (J2000.0): -81.9936 = -81:59:37.0 Error: 9.5 arcsec (radius, 90% conf.) Count-rate: 0.0208 [+0.0113, -0.0084] ct s^-1 Distance: 1341 arcsec from Fermi/GBM position. Flux: (8.6 [+4.7, -3.5])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) A catalogued source was also detected. The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/xrt_products/TILED_GRB00117. This circular is an official product of the Swift-XRT team.