GCN Circular 29423
Subject
GRB 210207B: AbAO optical upper limit
Date
2021-02-08T10:54:56Z (3 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), A. Pozanenko (IKI), R. Ya. Inasaridze (AbAO), V. R.
Ayvazian (AbAO), G. V. Kapanadze (AbAO), N. Pankov (HSE, IKI) report
on behalf of IKI-GRB-FuN:
We observed the field of GRB 210207B (Lien et al., GCN 29420) with
AS-32 telescope of Abastumani observatory (AbAO) in R-filter starting on
2021-02-08 (UT) 02:14:17. The optical afterglow (Lien et al., GCN
29420; Kumar et al., GCN 29421) is not detected in stacked image.
Date UT start t-T0 Filter Exp. OT Err. UL(3sigma)
(mid, days) (s)
2021-02-08 02:14:17 0.19837 R 47*60 n/d n/d 18.7
The photometry is based on nearby USNO-B1.0 stars
USNO-B1.0_id R2
1436-0267956 15.29
1436-0268040 15.52
The non-detection of the afterglow implies a jet break somewhere before
of our observations, or the source of the GRB 210207B is highly redshifted.