TITLE:   GCN CIRCULAR
NUMBER:  14813
SUBJECT: GRB 130603A: AAO optical observations
DATE:    13/06/07 18:24:37 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (IKI), R.Inasaridze (AAO), O. Kvaratskhelia (AAO), V. 
Ayvazian(AAO), Yu. Krugly (IA KhNU),  I. Molotov (KIAM), A. Pozanenko 
(IKI)  report on behalf of  larger GRB follow-up collaboration:

We observed the field of the Swift Swift GRB 130603A (Melandri et al., 
GCN 14731)with AS-32 (0.7m) telescope of Abastumani Observatory  on Jun. 
03 and Jun. 04. We obtained several unfiltered images of 300 s and 180 s 
exposures. The afterglow (Melandri  et al., GCN 14732) is well detected 
in  combined images in both epochs. Preliminary photometry

Date        T_start    t-t0,      exp,    OT
             (UT)       mid, d     s
2013-06-03  22:19:06   0.69976    9x300   20.30 +/- 0.09
2013-06-04  20:28:49   1.62003   13x180   21.60 +/- 0.19

is based on SDSS stars R mag, where R mag obtained via transformations 
ugriz in BVRI (Lupton, 2005):

n SDSS                  R     errR
1 J054806.91+825053.0  17.648 0.015
2 J054805.54+825456.1  16.750 0.013
3 J054706.99+825234.5  15.573 0.012