GCN Circular 15185
Subject
GRB 130831A: ISON-UAFO optical observations
Date
2013-09-07T23:20:51Z (11 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), A. Matkin (UAFO, ISON), A. Stepura (UAFO, ISON), 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
SANTEL-650 (0.65m) and VT-50 (0.5m) telescopes of UAFO/ISON-Ussuriysk
observatory starting on Aug. 31 (UT) 13:14:32, i.e. 10.3 minutes
after burst trigger. We took unfiltered images of 120s and 30s
exposures ending observations at (UT) 19:20:53.
In each initial frames we clearly detect afterglow. A preliminary
photometry of the afterglow in the initial frames are following
T_start T0+ Filter, Exposure, OT, OT_err
(UT) (mid, d) (s)
2013-08-31T13:14:32 0.00782 none 120 13.86 0.02
2013-08-31T13:l6:40 0.00931 none 120 13.75 0.02
2013-08-31T13:18:49 0.01080 none 120 13.78 0.02
The photometry is based on 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