GCN Circular 12380
Subject
GRB 110921A: optical observations in Mt. Terskol and Maidanak observatories
Date
2011-09-21T20:40:56Z (13 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), M. Andreev, A. Sergeev (Terskol Branch of Institute of
Astronomy), M. Ibrahimov (MAO) on behalf of larger GRB follow up
collaboration report:
We observed the field of the Swift GRB 110921A (Baumgartner et al., GCN
12373) with Zeiss-600 telescope of Mt. Terskol observatory and AZT-22
telescope of Maidanak observatory on Sep. 21. Several images were taken in
both observatories in R filter. Within the enhanced XRT error box (Goad et
al., GCN 12379) we do not detect the candidate of optical counterpart of
GRB 110921A (Xin et al., GCN 12377). Preliminary photometry of a combined
image (Zeiss-600) and a single image of AZT-22 is based on the nearby USNO
B1.0 stars:
UT Filter, Exposure, OT, Upper Limit (3 sigma)
Telescope
(mid) (s)
Sep.21 16:50 R 1800 n/d 21.1
Zeiss-600
Sep.21 17:48 R 300 n/d 21.2
AZT-22
Since our photometry is somewhat deeper than photometry of the candidate
(Xin et al., GCN 12377), we could suggest the candidate is a real afterglow
of GRB 110921A.