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GCN Circular 32173

GRB 220606B: Swift follow-up observations
2022-06-07T13:36:38Z (2 years ago)
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

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

This circular is an official product of the Swift team.
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