GCN Circular 2964
Subject
Unusual optical transient (GRB ???)
Date
2005-01-19T17:12:22Z (20 years ago)
From
Jean-Luc Atteia at Lab d Astrophys.,OMP,Toulouse <atteia@ast.obs-mip.fr>
Subject: Unusual optical transient (GRB ???)
F. Malacrino, JL. Atteia (LA-OMP), M. Boer (OHP), A. Klotz (CESR-OMP),
C. Veillet, J-C. Cuillandre (CFHT), JJ. Kaavelars (HIA-NRC)
report on behalf of the GRB Real Time Analysis System at CFHT.
We observed an unusual optical transient recorded within the course of
the Very-Wide Survey of the CFHTLS ( http://www.cfht.hawaii.edu/Science/CFHLS/ ).
The transient is seen on January 16, 2005 in a series of three consecutive
exposures with the following relative g� magnitudes (accurate to ~0.5 mag):
16-01-2005, 29408s, g�= 20.5 � 0.1
16-01-2005, 33036s, g�= 22.1 � 0.1
16-01-2005, 36299s, g�= 23.0 � 0.5
On January 17th the transient is not detected down to g�~23.5
The coordinates (J2000) of the transient are:
RA = 08 43 55.21 � 2�
DEC = 20 02 22.2 � 2�
We have no color information on the transient, and there is no object in
the USNO-B1 Catalog (Monet 2003) at this position.
Given the fast decay of the source we consider that it is more likely to be
a faint flare star (like the transient reported in GCNs 2849, 2850, 2851)
rather than a GRB afterglow .
We nevertheless communicate the position of this transient to the community
of GRB observers in case there is some opportunity for follow-up at radio or
optical wavelengths with large instruments.