[vsnet-grb-info 17778] GRB 160321A: AbAO optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19219
SUBJECT: GRB 160321A: AbAO optical observations
DATE:    16/03/22 20:25:03 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

E. Mazaeva (IKI), A. Volnova
  (IKI), R. Inasaridze (AbAO), V. Ayvazian (AbAO), I. Molotov (KIAM), A. 
Pozanenko (IKI) report on behalf of larger
GRB follow-up collaboration:

We observed the field of Swift GRB 160321A (Stamatikos et al., GCN 
19211) with AS-32 (0.7m) telescope of Abastumani Observatory starting on 
Mar. 21 (UT) 16:26:45. We obtained several unfiltered images of the 
field. We do not detect any source within enhanced XRT error circle 
(Beardmore et al., GCN 19213) down to 21.9m. A probable source (S/N = 2) 
detected 3.5 arcsec South from the center of XRT error circle (Beardmore 
et al., GCN 19213) in coordinates (J2000) 06:37:40.74 +05:44:48.2 +/- 
0.5 arcsec in both coordinates.

Preliminary photometry of the field is following


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

2016-03-21 16:26:45   0.06839  none    41*120  21.9

Photometry is based on nearby USNO-B1.0 stars
USNO-B1_id   R2
0956-0104166 16.23
0957-0105913 15.38
0957-0106394 14.58
0956-0104566 15.41