[vsnet-grb-info 18472] GRB 160912A: Mondy optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19920
SUBJECT: GRB 160912A: Mondy optical observations
DATE:    16/09/13 13:19:46 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

A. Volnova (IKI),  A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva 
(IKI), I. Korobtsev (ISTP)  report on behalf of larger GRB follow-up 
collaboration:

We observed the field of the GRB 160912A (Cannizzo et al.
GCN 19912) with  AZT-33IK telescope of Sayan observatory (Mondy) 
starting on Sep., 12 (UT) 18:14:25. We obtained several images in 
R-filter. We  clearly detected optical afterglow (Tanvir et al., GCN 
1991). Coordinates of the afterglow are (J2000)   20 05 59.64
+57 33 55.2 with uncertainty of 0.4 arcsec in both coordinates. The 
afterglow is 5 arcsec from nearby star (USNO-B1.0 1475-0371357 (J2000) 
RA = 20:06:00.32 Dec = +57:33:57.0 R2 = 18.21) and within enhanced XRT 
position (Beardmore et al. GCN 19915). Preliminary photometry  of the 
afterglow is following

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

2016-09-12  18:14:25   0.10883    R     30*120 22.57 +/-0.08  23.5

Photometry is based on nearby USNO-B1.0 stars
ID             RA           Dec        R2
2 1475-0371275 20:05:49.83 +57:33:12.9 17.09
3 1475-0371352 20:05:59.47 +57:32:43.8 17.46
4 1475-0371174 20:05:41.08 +57:33:00.0 17.43
5 1475-0371504 20:06:16.57 +57:32:46.8 17.62

The finding chart can be found at 
http://grb.rssi.ru/GRB160912A/GRB160912A_160912_AZT33IK_fc.png