TITLE: GCN CIRCULAR NUMBER: 32173 SUBJECT: GRB 220606B: Swift follow-up observations DATE: 22/06/07 13:36:38 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp (PSU), J.A. Kennea (PSU), P.A. Evans (U. Leicester), A. Breeveld (UCL-MSSL) report on behalf of the Swift team: Swift-XRT has performed follow-up observations of the Swift/BAT-GUANO-detected burst GRB 220606B (Tohuvavohu et al., GCN Circ. 32167), collecting 4.9 ks of Photon Counting (PC) mode data between T0+44.9 ks and T0+68.8 ks. No credible X-ray afterglow candidate has been detected within the BAT-GUANO error circle (Tohuvavohu, GCN Circ. 32170) down to a 0.3 - 10 keV count-rate upper limit of ~ 2e-3 ct/s (3sigma c.l.). The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/ToO_GRBs/00021504. Swift-UVOT began settled observations 45.1 ks after the trigger. No optical afterglow consistent with the BAT-GUANO position is detected. The 3.9 ks exposure in the white filter gives an upper limit of >21.9 mag. This circular is an official product of the Swift team.