[vsnet-grb-info 26749] GRB 201104B: TSHAO optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28852
SUBJECT: GRB 201104B: TSHAO optical observation
DATE:    20/11/06 11:11:37 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

S. Belkin (IKI), N. Pankov (HSE), I. Reva (FAPHI), A. Pozanenko (IKI) 
report on behalf of GRB-IKI-FuN:

We observed the field of GRB 201104B (Sbarufatti et al., GCN  28825) 
with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory 
starting on Nov. 05 (UT) 12:51:33.

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 detected in stacked image in R-filter. Preliminary 
photometry of the afterglow is following.

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

2020-11-05 12:51:33 0.82641  R      43*90 21.20 0.1 22.2

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

USNO-B1.0_id R2
0979-0003163 17.51
0979-0003223 17.47

We note the presence of a galaxy 3.6" South-East from the afterglow. The 
galaxy is clearly visible in Pan-STARRS and SDSS and detected in 
USNO-B1.0, PS1 and SDSS DR12 (J002051.50+075026.5).