[vsnet-grb-info 13875] GRB 130831A: optical observation in Chuguev AO

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15189
SUBJECT: GRB 130831A: optical observation in Chuguev AO
DATE:    13/09/07 23:56:01 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

A. Volnova (IKI), Yu. Krugly (IA KhNU), I. Slyusarev (IA KhNU), I. 
Molotov (KIAM), A. Pozanenko (IKI) report on behalf of  larger GRB 
follow-up collaboration:

We observed the afterglow  (Hagen et al., GCN  15139; Guidorzi et al., 
GCN 15140) of the Swift GRB 130831A (Hagen et al., GCN  15139)  with 
AZT-8 (0.7m) telescope of Institute of Astronomy, Kharkiv National 
University in R filter starting on Sep. 01 (UT) 19:37:49.  A preliminary 
photometry of combined images is based on  SDSS DR9 stars

T_start              T0+       Filter, Exposure, OT,    OT_err
(UT)                 (mid, d)            (s)

2013-09-01T19:37:49  1.29474   R       28x120    21.26   0.07

Reference stars SDSS-DR9, (R mag, transformation by Lupton 2005)

N	SDSS id			R(Lupton)errR
1	J235443.71+292539.3	13.491	 0.016
2	J235438.60+292547.3	14.136	 0.015
3	J235423.64+292452.8	17.120	 0.016