TITLE:   GCN CIRCULAR
NUMBER:  29174
SUBJECT: GRB 201223A: AbAO optical observations
DATE:    20/12/24 21:31:45 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

N. Pankov (HSE, IKI), A. Pozanenko (IKI), S. Belkin (IKI), R. Ya. 
Inasaridze (AbAO), V. R. Ayvazian (AbAO),  G. V. Kapanadze (AbAO), A. 
Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of  GRB 201223A (Gropp et al., GCN 29158;  Wood et
al., GCN 29161) with AS-32 telescope of Abastumani observatory (AbAO) in 
R-filter. The optical afterglow (Lipunov et al., GCN 29157; Gropp
et al., GCN 29158; Zhu et al., GCN 29159; Hu et al., GCN 29160;
Hosokawa et al., GCN 29164; Romanov et al., GCN 29165; Xin et al., GCN
29166; Belkin et al., GCN 29167; Kumar et al., GCN 29168; Xu et al., GCN 
29169; Gupta et al., GCN 29173) is detected in stacked images.

Date       UT start   t-T0    Filter Exp.    OT    Err.  UL(3sigma)
                        (mid, days)     (s)


2020-12-23 19:39:59   0.0733  R      8*60   19.38  0.17  19.8
2020-12-23 21:19:22   0.1517  R     35*60   20.28  0.13  20.9

The photometry is based on nearby USNO-B1.0 stars.