Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 34986

GRB 231110A: Swift-XRT afterglow detection
2023-11-11T20:48:23Z (6 months ago)
Phil Evans at U of Leicester <>
A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), M. Perri
(SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti
(INAF-OAB), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU), J. D. Gropp
(PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT

Swift-XRT has performed follow-up observations of the
Swift-BAT-detected burst GRB 231110A, collecting 10 ks of Photon
Counting (PC) mode data between T0+8.9 ks and T0+61.1 ks. 

Four uncatalogued X-ray sources are detected consistent with being
within 296 arcsec of the Swift-BAT position, of which one ("Source 2")
is believed to be the afterglow.  The position of this source is RA,
Dec=356.2752, +82.6447 which is equivalent to:

RA (J2000): 23:45:6.05
Dec(J2000): +82:38:40.9

with an uncertainty of 5.1 arcsec (radius, 90% confidence).  This
position is 85 arcsec from the Swift-BAT position.  There is evidence
that the source may be fading, however we cannot constrain the decay at
the current time

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

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

Looking for U.S. government information and services? Visit