GCN Circular 31004
Subject
GRB 211023A: Mondy optical observations
Event
Date
2021-10-26T12:06:17Z (4 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov (HSE),
report on behalf of GRB IKI FuN:
We observed the GRB 211023A (Fermi GBM team, GCN 30958) with AZT-33IK
telescope of Sayan observatory (Mondy) starting on 2021-10-25 (UT)
15:16:32. We obtained 17 images in R-filter. The afterglow of the GRB
211023A (Lipunov et al., GCN 30977; Kann et al. GCN 30982; Hu et
al. GCN 30990) is clearly detected. Preliminary photometry of the
afterglow in a stacked image is following
Date UT start t-T0 Filter Exp. OT Err. UL(3sigma)
(mid, days) (s)
2021-10-25 15:16:32 2.10265 R 17*120 19.87 0.15 21.0
The photometry is based on the nearby USNO-B1.0 stars
RA DEC R2
04:53:23.10336 +85:19:26.4720 14.09
04:52:47.26344 +85:22:52.1508 15.75
Based on photometry reported early (Kann et al. GCN 30982; Hu et al.
GCN 30990) we can approximate a light curve of the afterglow as a power
law with the index of 1.49+/-0.03. See also the figure of the light curve in
http://grb.rssi.ru/GRB211023A/GRB211023A_LC.png