[vsnet-grb-info 9681] GRB 100725B: Maidanak optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11149
SUBJECT: GRB 100725B: Maidanak optical upper limit
DATE:    10/08/27 14:11:00 GMT
FROM:    Alina Volnova at SAI MSU  <alinusss at gmail.com>

A. Volnova (SAI MSU), A. Pozanenko (IKI), B. Satovski (Astrotel), M.
Ibrahimov (MAO) report on behalf of  larger GRB  follow-up
collaboration:

We observed the field of the Swift GRB 100725B (Baumgartner et al.,
GCN 10983) with AZT-22 telescope of  Maidanak observatory in R-band on
Jul.25 between (UT) 16:36:55 - 17:51:54 under good waether conditions
(seeing 0.7"). We took 9 images with exposure 300 seconds. We do not
detect any sources in enhanced XRT error circle (Goad et al. GCN
10986). The upper limit (3 sigma) of stacked image is based on
SDSS-DR7 is the following:

t-t0,d	filter	exp., 	uplim
0.24295	R	9x300	22.7