GCN Circular 17669
Subject
GRB 150323C: Khureltogot optical observations
Date
2015-04-04T11:07:51Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), S. Schmalz (AIP), N. Tungalag (Research Center of
Astronomy and Geophysics MAS), 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 150323C (Amaral-Rogers et al., GCN 17621)
with ORI-40 telescope of Khureltogot observatory starting on Mar., 23 (UT)
17:20:51, i.e. ~15 minutes after burst trigger. We obtained 180 unfiltered
images of 60 s exposure. Within enhanced Swift-XRT error circle (Osborne et
al., GCN 17633) we detect optical afterglow (Xu et al. GCN 17625, Xin et
al. GCN 17631; Watson et al. GCN 17632). Preliminary photometry of the
afterglow in combined images is following
Date UT start t-T0 Filter Exp. OT OT_err
(mid, days) (s)
2015-01-23 17:20:51 0.01449 none 10*60 21.1 0.3
2015-01-23 17:31:40 0.02199 none 10*60 20.5 0.25
2015-01-23 17:42:28 0.02950 none 10*60 20.8 0.25
2015-01-23 17:53:17 0.03700 none 10*60 20.2 0.2
2015-01-23 18:04:04 0.04451 none 10*60 20.0 0.2
2015-01-23 18:14:54 0.06199 none 35*60 21.3 0.3
2015-01-23 18:54:26 0.09409 none 39*60 21.0 0.3
2015-01-23 19:57:04 0.13649 none 40*60 21.5 0.4
Photometry is based on SDSS DR9 stars:
SDSS9_id R(Lupton)
J125026.13+501147.9 16.16
J125023.08+501048.2 16.84
Our photometry confirms non-monotonic behaiviour of a lighr curve of the
afterglow mentioned by Xin et al. (GCN 17631).
The light curve of GRB 150323C afterglow can be found in
http://grb.rssi.ru/GRB150323C/GRB150323C_ORI40_lc.png