[vsnet-grb-info 17172] GRB 151027A: SAO RAS optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18521
SUBJECT: GRB 151027A: SAO RAS optical observations
DATE:    15/10/28 23:18:01 GMT
FROM:    Moskvitin Alexander at SAO RAS  <mosk at sao.ru>

A. Moskvitin (SAO RAS, Russia), report on behalf of the larger GRB
follow-up team:

The field of the GRB 151027A (Maselli et al., GCNC #18478) was observed
with the Zeiss-1000, 1 meter telescope of SAO RAS on the October, 28.
The observations started 36.3 hours after the trigger.
Two series of 300 sec. images in Rc band: 6 frames (16:13:57--16:56:20 UT)
and 3 frames (17:32:15--17:50:33 UT) were obtained under the tolerable
weather conditions.

The OT is clearly detected in the stacked frames:
#  T_mid-T0,h   exp,s      R_mag
1  36.612       6 x 300    18.7 +/- 0.1
2  37.717       3 x 300    18.9 +/- 0.1

The photometry is based on nearby USNO-B1 stars proposed
by A. Pozanenko (IKI RAS). The observations were provided with the help
of the SAO RAS staff: V. Komarov, O. Spiridonova and R. Uklein.