GCN Circular 28505
Subject
GRB 200922A: Chilescope optical observations
Event
Date
2020-09-26T16:18:20Z (5 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), S. Belkin (IKI), A. Volnova (IKI), P. Minaev (IKI),
N. Pankov (HSE) report on behalf GRB IKI FuN collaboration:
We observed the field of GRB 200922A (Moss et al., GCN 28471) with
RC-1000 Chilescope observatory in r'-filter starting on 2020-09-22 (UT)
23:25:05. In a single obtained image of 1200 s exposure we cannot
resolve the OT reported earlier (Moss et al., GCN 28471; Izzo et al.,
GCN 28478; Siegel et al., GCN 28482; Malesani et al., GCN 28492).
Instead we subtract the flux of nearby star from SkyMapper DR1.1 from
the (nearby star + OT) photometry.
Preliminary photometry of the OT after the above-mentioned procedure is
following.
Date UT start t-T0 Filter Exp. OT(AB) Err. UL(AB)
(mid, days) (s)
2020-09-22 23:25:05 0.478 r' 1200 18.92 0.05 20.7
The photometry is based on nearby SkyMapper DR1.1 stars.