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GCN Circular 22931

GRB 180703A: Swift-XRT afterglow detection
2018-07-09T13:33:20Z (6 years ago)
Antonino D'Ai at IASF-PA <>
S.L. Gibson (U. Leicester), Z. Liu (NAOC / U. Leicester), P. D'Avanzo
(INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), S. J. LaPorte
(PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), J.P. Osborne
(U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

Swift-XRT has conducted further observations of the field of the
Fermi/LAT-detected burst GRB 180703A (Racusin et al. GCN Circ. 22883).
The observations now extend from T0+17.3 ks to T0+263.7 ks. The source
previously reported by Gibson et al. (GCN Circ. 22891), "Source 1", is 
believed to be the afterglow.  The position of this source is RA,
Dec=6.4699, -67.1802 which is equivalent to:

RA (J2000): 00:25:52.79
Dec(J2000): -67:10:48.7

with an uncertainty of 4.8 arcsec (radius, 90% confidence).  This
position is 5.7 arcmin from the Fermi/LAT position.  The source is
fading with alpha >0.8.

The results of the XRT-team automatic analysis are available at
The results of the full analysis of the tiled XRT observations are
available at

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