TITLE:   GCN CIRCULAR
NUMBER:  14200
SUBJECT: GRB 121123A: optical observations
DATE:    13/02/13 16:34:45 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

Yu. Krugly (Institute of Astronomy of Kharkiv National University), 
R.Inasaridze, O. Kvaratskhelia(Abastumani Astrophysical Observatory), 
I. Molotov (KIAM), A. Pozanenko (IKI)  report on behalf of  larger GRB 
follow-up collaboration:

We observed the field of the Swift GRB 121123A (Helder et al., GCN 
13982) with AC-32 (0.7m Maksutov) telescope of Abastumani Observatory, 
starting on Nov. 23 (UT) 15:18. We took several unfiltered images of 180 
s exposure. We clearly detected the afterglow (Helder et al., GCN 13982; 
Zhao et al., GCN 13983) in every  single image. The photometry of the 
stacked images is based on USNO-B1.0 stars (R2):

Start,    T0+,        Filter,   Exp.,  OT
(UT)      (mid),days

15:18:28  0.2229      none      4x180  19.01 +/- 0.10
15:33:10  0.2337      none      4x180  18.96 +/- 0.09
15:48:15  0.2448      none      4x180  18.88 +/- 0.08
16:02:57  0.2551      none      4x180  19.17 +/- 0.11
16:02:57  0.2642      none      4x180  18.94 +/- 0.10
16:28:40  0.2729      none      4x180  19.06 +/- 0.11