[vsnet-grb-info 16754] GRB 150711A: Burakan-ISON optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18035
SUBJECT: GRB 150711A: Burakan-ISON optical observations
DATE:    15/07/18 22:00:01 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

E. Mazaeva (IKI), V. Nevskiy (ISON) I. Molotov (KIAM), A. Pozanenko 
(IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150711A (Bernardini et al. GCN 18011) with 
the 40 cm telescope of Burakan-ISON observatory starting on Jul., 11 
(UT) 18:36:16, i.e. ~13 min after burst trigger. We obtained several 
unfiltered images. In a combined image we  do not detect any source 
within the XRT error box (Osborne et al. GCN 18012) down to a limiting 
magnitude of R = 16.9

Date       UT start  t-T0      Filter   Exp.  OT    UL(3 sigma)
                     (mid, days)         (s)

2015-07-11 18:36:16  0.01250   none     9*60  n/d   16.9

The photometry is based on nearby USNO-B1.0  stars.