GCN Circular 30712
Subject
GRB 210822A: TSHAO optical observation
Event
Date
2021-08-25T09:49:39Z (4 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), A. Kusakin (FAP), I. Reva (FAP), Pozanenko (IKI), N.
Pankov (HSE), V. Kim (FAP) report on behalf of GRB-IKI-FuN:
We observed GRB 210822A (Page et al., GCN 30677; Wang et al., GCN
30678; Prasad et al., GCN 30693; Frederiks et al., GCN 30694) with
Zeiss-1000 telescope of Tien Shan Astronomical Observatory on Aug. 22
(UT) 15:48:55 -- 18:48:47. We obtained series with 20 and 30 sec
exposition in R-filter.
The optical afterglow (Page et al., GCN 30677; Zheng et al., GCN 30679;
Butler et al., GCN 30680; Fu et al., GCN 30684; Zhu et al., GCN 30692;
Romanov et al., GCN 30701; Guelbenzu et al., GCN 30703; Siegel et al.,
GCN 30710) at redshift z = 1.736 (Zhu et al., GCN 30692) is detected in
stacked images. Preliminary photometry of the afterglow in a stacked
image of the second series is following.
Date UT start t-T0 Filter Exp. OT Err. UL(3 sigma)
(mid, days) (s)
2021-08-22 17:26:41 0.36184 R 196*20 18.63 0.03 21.0
The photometry is based on nearby USNO-B1.0 stars.
USNO-B1.0
RA Dec R2
20:18:06.64416 +05:17:24.1404 12.33
20:17:59.55288 +05:18:19.5912 13.05