[vsnet-grb-info 26753] GRB 201104B: Kitab optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28856
SUBJECT: GRB 201104B: Kitab optical observations
DATE:    20/11/06 17:01:34 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

S. Belkin (IKI), A. Zhornichenko (KIAM),  A. Pozanenko (IKI), V. 
Agletdinov (KIAM), Sh. Ehgamberdiev (UBAI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 201104B (Sbarufatti et al., GCN  28825) 
with Kitab-ISON RC-36  telescope in Clear filter.  Observation started 
on Nov. 4  (UT) 18:44:28, i.e. 77 minutes after trigger.
The optical afterglow (Marshall et al., GCN 28827; Vielfaure  et al., 
GCN 28840; Oates  et al., GCN 28851) at redshift z = 1.954 (Vielfaure et 
al., GCN 28840) is marginally (S/N = 1.8) detected in stacked image. 
Preliminary photometry of the afterglow is following.

  Date,      UT start, t-T0,   Exp.,  Filter, OT,   S/N  UL(3 sigma)
                     (mid, days)

2020-11-04  18:44:28 0.0741   72*60  CR      20.4  1.8   20.0

The photometry is based on nearby USNO-B1.0 stars, R magnitude.
USNO-B1.0_id R2
0979-0003163 17.51
0979-0003223 17.47