GCN Circular 31003
Subject
GRB 211023B: Mondy optical afterglow confirmation
Event
Date
2021-10-26T11:09:14Z (5 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), S. Belkin (IKI), E. Klunko (ISTP), N. Pankov (HSE),
report on behalf of GRB IKI FuN:
We observed the field of GRB 211023B (Dichiara et al., GCN 30960) with
AZT-33IK telescope of Sayan observatory (Mondy) starting on 2021-10-23
(UT) 21:23:21. We obtained 60 images in R-filter. We confirm afterglow
of the GRB 211023B (Dichiara et al., GCN 30960; Kuin et al. GCN 30975;
Kann et al. GCN 30995; O'Connor et al., GCN 31000; Rastinejad et al.,
GCN 31002). Preliminary photometry of the afterglow in stacked images
is following
Date UT start t-T0 Filter Exp. OT Err. UL(3sigma)
(mid, days) (s)
2021-10-23 21:23:21 0.15613 R 15*60 20.46 0.31 20.5
2021-10-23 21:23:21 0.03297 R 60*60 20.97 0.40 20.9
The photometry is based on the nearby USNO-B1.0 stars
RA DEC R2
11:21:12.41280 +39:08:38.1120 15.33
11:21:05.20872 +39:04:33.9600 14.18
We note the obtained magnitudes are in agreement with non-detections of
the optical counterpart (Lipunov et al., GCN 30964; Pozanenko et al.,
GCN 30972; Watson et al., GCN 30973; Yu et al., GCN 30976).