GCN Circular 3990
Subject
GRB 050915a: IR Transient
Event
Date
2005-09-16T14:52:12Z (20 years ago)
From
Josh Bloom at UC Berleley <jbloom@astron.berkeley.edu>
J. S. Bloom (UC Berkeley) reports:
"Further imaging of the field of GRB 050915a (GCNs 3977, 3979, 3983)
with the PAIRITEL 1.3m began at 2005-09-16 10:58:38 UTC. We confirm
that the source present in the first epoch (GCN 3984) has faded and
is thus the likely IR afterglow of GRB 050915a. In particular, the
mean H-band magnitude of the source during the first epoch was
H=18.25 +/- 0.16. The source was undetected in the second epoch, with
an approximate 3-sigma detection threshold of H(upper limit)=18.55 mag.
An improved astrometric solution was obtained for the imaging on
2005-09-15 UTC, yielding a J2000 position of the IRT of:
RA = 05:26:44.804
DEC = -28:00:59.27
The 1 sigma uncertainties relative to the 2MASS catalog are 0.18" and
0.09" in RA and DEC, respectively. This position is 3.2" from the
revised XRT position reported by Grupe et al. (GCN 3983).
We encourage deep z band and NIR imaging."
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