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GCN Circular 32464

GRB 220810A: Swift-XRT observations
2022-08-13T09:28:21Z (2 years ago)
Phil Evans at U of Leicester <>
J. D. Gropp (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), A.P.
Beardmore (U. Leicester), J.P. Osborne (U. Leicester), A. Melandri
(INAF-OAB), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the second optical
afterglow candidate observed by MeerLICHT (de Wet et al. GCN Circ.
32460) of the Fermi/GBM detected burst GRB 220810A (Fermi GBM team, GCN

32455), collecting 4.9 ks of Photon Counting (PC) mode data between
T0+156.3 ks and T0+180.2 ks. 

No X-ray sources have been detected consistent with being within 9.9
arcsec of the MeerLICHT optical afterglow candidate position. The
3-sigma upper limit in the field is 0.003 ct  s^-1, corresponding to a
0.3-10 keV observed flux of 1.1e-13 erg cm^-2 s^-1 (assuming a typical
GRB spectrum).

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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