GCN Circular 23032
P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), A. Tohuvavohu (PSU), S.L. Gibson (U. Leicester), Z. Liu (NAOC / U. Leicester), J.P. Osborne (U. Leicester), A. D'Ai (INAF-IASFPA) 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 180722A (Shimomukai et al. GCN Circ. 23005) in a series of observations tiled on the sky. The total exposure time is 1.2 ks, distributed over 7 tiles; the maximum exposure at a single sky location was 391 s. The data were collected between T0+45.7 ks and T0+47.1 ks, and are entirely in Photon Counting (PC) mode. No X-ray sources have been detected. The 3-sigma upper limit in the field (not including the regions where the tiles overlap) ranges from ~0.04 to ~0.12 ct s^-1, corresponding to a 0.3-10 keV observed flux of 1.8e-12 to 4.9e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum). The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/xrt_products/TILED_GRB00071. This circular is an official product of the Swift-XRT team.