Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 23097

GRB 180806A: Swift-XRT afterglow detection
2018-08-07T22:15:00Z (6 years ago)
Antonino D'Ai at IASF-PA <>
S.L. Gibson (U. Leicester), Z. Liu (NAOC / U. Leicester), V. D'Elia
(ASDC), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), B. Sbarufatti
(INAF-OAB/PSU), D.N. Burrows (PSU), A. Tohuvavohu (PSU) and P.A. Evans
(U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/GBM-detected burst GRB 180806A (Malacaria et al. GCN Circ.
23095), collecting 1.8 ks of Photon Counting (PC) mode data between
T0+57.6 ks and T0+76.2 ks. 

Two uncatalogued X-ray sources are detected, of which one ("Source 1")
is fading with 3-sigma significance, and is therefore likely the GRB
afterglow.  The position of this source is RA, Dec=11.5536, +24.3370
which is equivalent to:

RA (J2000): 00:46:12.86
Dec(J2000): +24:20:13.2

with an uncertainty of 5.0 arcsec (radius, 90% confidence). 
This position is 1.3 arcsec from the Fermi/GBM position and 2.7 arcsec
from the OT position reported by Lipunov (GCN 23091) and Watson (GCN

The source is fading with alpha >2.2.

The results of the XRT-team automatic analysis of the likely afterglow
are 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