[vsnet-grb-info 16437] GRB 150413A: ISON-Ussuriysk optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17718
SUBJECT: GRB 150413A: ISON-Ussuriysk optical observations
DATE:    15/04/17 21:33:14 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

E. Mazaeva (IKI),  A. Stepura (UAFO, ISON),  A. Matkin (UAFO, ISON), A. 
Volnova (IKI), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of 
larger GRB follow-up collaboration:

We observed the field of the GRB 150413A (Markwardt  et al., GCN 17688) 
with SANTEL-650 (0.65m)  telescope of UAFO/ISON-Ussuriysk observatory 
sstarting on Apr., 14 (UT) 11:48:05.   The afterglow   (Ivanov et al., GCN 
17689) is clearly detected in a combined image. Preliminary photometry the 
unfiltered combined image  is following

Date            UT start   t-T0        Filter     Exp.     OT      OT_err
                                 (mid, days)          (s)

2015-04-14  11:48:05  0.95859   none     117*60  20.35   0.15

The photometry is based on nearby USNO-B1.0  stars