TITLE:   GCN CIRCULAR
NUMBER:  14321
SUBJECT: GRB 130313A: optical upper limit in Mondy observatory
DATE:    13/03/16 19:54:28 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A.Volnova (SAI MSU/IKI), E. Klunko (ISTP), A. Pozanenko (IKI) report on 
behalf of larger GRB follow-up collaboration:

We observed the field of the Swift GRB 130313A (Gompertz  et al., GCN 
14293) with AZT-33IK telescope of Sayan observatory (Mondy) on March 13 
between (UT) 17:45:47 - 22:55:49. We took several images in R-filter of 90 s 
exposure which cover  partially the refined BAT error box (Barthelmy et al., 
GCN 14296).  Within  XRT position (Gompertz et al., GCN  14297; Osborne et 
al., GCN  14300) we do  not detect any source. Preliminary photometry of 
combined images is following

UT start,    t-t0           filter      Exp.   OT      UL (3 sigma)
             (mid, days)                (s)

17:54:56    0.06737        R          20x90   n/d     20.3
17:54:56    0.17047        R        147x90   n/d     23.3

The photometry is based on two SDSS DR8  stars
SDSS J154537.18-001931.3 RA = 15 45 37.18 Dec = -00 19 31.3 (J2000), R = 
18.95
SDSS J154535.15-001918.8 RA = 15 45 35.15 Dec = -00 19 18.8 (J2000), R = 
16.76