[vsnet-grb-info 14603] GRB 140304A: Mondy optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15917
SUBJECT: GRB 140304A: Mondy optical observations
DATE:    14/03/04 15:02:59 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

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

We observed the field of GRB 140304A (Evans et al., GCN 15915)  with 
AZT-33IK telescope of Mondy observatory starting on Mar. 04 (UT) 
13:54:10, i.e. ~0.5 hour after burst trigger. In the first images of 60 
s exposure we clearly detected afterglow of GRB 140304A reported by 
Gorbovskoy et al. (GCN 15914) and Xu et al. (GCN 15916).  Preliminary 
photometry of the fading afterglow is following:

date       UT start   t-T0      Exp.  Filter  OT
                      (mid, days) (s)
2014-03-04 13:54:10  0.02406    6*60  R       20.29 ± 0.17

The photometry is based on reference stars SDSS-DR9, (R mag,
transformation by Lupton 2005):

N  SDSS_id          R(Lupton)   err
J020233.12+332550.3 15.665 0.012
J020219.91+332738.5 14.785 0.012