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GCN Circular 23032

GRB 180722A: Swift-XRT observations
2018-07-24T14:33:45Z (6 years ago)
Boris Sbarufatti at PSU <>
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

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