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GCN Circular 26699

ANTARES 200108A: No detection by Swift-XRT
2020-01-10T16:19:42Z (4 years ago)
Phil Evans at U of Leicester <>
P.A. Evans (U. Leicester), A. Tohuvavohu (U. Toronto), J.A. Kennea (PSU)
and S.B. Cenko (GSFC) report on behalf of the Swift/XRT team:

Swift performed a series of 19 observations tiling the sky area of the 
Fermi-LAT / ANTARES coincident event ANTARES 200108A (Turley et al., GCN 
Circ. 26674). The observations were centred on RA=02h 49m 56.5s, 
Dec=-18d 05' 17", with a radius of ~50', and were carried out between 
22:53:41 UT on Jan 8 until 00:37:14 UT on Jan 9; the detection of GRB 
200109A subsequently interrupted the campaign. We gathered between 30 s 
and 150 s of exposure per tile, with the typical exposure being 110 s.

No X-ray sources were found, with a typical upper limit of 0.06 ct/sec 
(0.3-10 keV).

Assuming a standard AGN spectrum (NH=3e20, Gamma=1.7) this corresponds 
to a 0.3-10 keV observed flux of 2.6 x 10^-12 erg/cm^-2 s^-1.
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