[vsnet-grb-info 27419] GRB 210212A: Mondy optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29522
SUBJECT: GRB 210212A: Mondy optical observations
DATE:    21/02/18 00:17:06 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

S. Belkin (IKI),  A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov (HSE) 
report  on behalf of GRB IKI FuN:

We observed the field of GRB 210212A (Troja et al., GCN 29487) with 
AZT-33IK telescope of Sayan observatory (Mondy) starting on 2021-02-12 
(UT) 14:39:29, i.e. 0.45 days after GRB trigger and reasonable FWHM of 
about 2.7". Within enhanced XRT position (Beardmore et al., GCN 29489) 
we found an object. Preliminary photometry of the object in a combined 
image is following

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

2021-02-12 14:39:29   0.44527    R      27*120  22.20 0.28  22.4

The photometry is based on the nearby USNO-B1.0 stars
USNO-B1.0_id R2
0972-0060540 15.06
0972-0060545 15.99

The object could be an afterglow of the GRB 210212A which is not 
separated from (possible host) galaxy (Heintz  et al., GCN 29498; 
Dichiara et al., GCN 29507).