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GCN Circular 33072

GRB 221215A: Swift-XRT observations
2022-12-16T15:41:34Z (2 years ago)
Phil Evans at U of Leicester <>
K.L. Page (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi 
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J. D. Gropp (PSU), S.
Dichiara (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester) and
P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Swift/BAT-GUANO-detected burst GRB 221215A, collecting 2.8 ks of Photon
Counting (PC) mode data between T0+97.3 ks and T0+113.8 ks. 

No X-ray sources have been detected consistent with being within 296
arcsec of the Swift/BAT-GUANO position. The 3-sigma upper limit in the
field is 0.005 ct  s^-1, corresponding to a 0.3-10 keV observed flux of
1.9e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum).

An uncatalogued was detected, however this was too far from the GRB
position to be the afterglow.

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at

This circular is an official product of the Swift-XRT team.
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