TITLE: GCN CIRCULAR NUMBER: 32633 SUBJECT: GRB 221008A: Swift-XRT observations DATE: 22/10/09 15:09:33 GMT FROM: Phil Evans at U of Leicester S. Dichiara (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the MAXI-detected burst GRB 221008A (Soejima et al. GCN Circ. 32630) in a series of observations tiled on the sky. The total exposure time is 1.2 ks, distributed over 4 tiles; the maximum exposure at a single sky location was 466 s. The data were collected between T0+50.0 ks and T0+51.4 ks, and are entirely in Photon Counting (PC) mode. No uncatalogued X-ray sources have been detected. The 3-sigma upper limit in the field (not including the regions where the tiles overlap) ranges from ~0.03 to ~0.06 ct s^-1, corresponding to a 0.3-10 keV observed flux of 1.1e-12 to 2.4e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum). A previously-catalogued X-ray source has been detected, however because it is a catalogued object it is unlikely to be the afterglow. 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_GRB00109. This circular is an official product of the Swift-XRT team.