TITLE:   GCN CIRCULAR
NUMBER:  27162
SUBJECT: GRB 200219С: Mondy and TSHAO optical observations
DATE:    20/02/21 10:54:35 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

I. Reva (FAPHI), A. Pozanenko (IKI), M. Krugov (FAPHI), with Zeiss-1000 
1-m telescope of Tien Shan Astronomical Observatory

A. Pozanenko (IKI), S. Belkin (IKI),  E. Klunko (ISTP), I. Reva (FAPHI), 
  M. Krugov (FAPHI), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf 
of IKI-GRB-FuN:

We observed the field of GRB 200219С (The Fermi GBM team, GCN 27145; 
Dirirsa et al., GCN 27151; Hamburg et al., GCN  27155) with AZT-33IK 
1.5-m telescope of Sayan observatory (Mondy) starting on Feb. 20 (UT) 
21:21:45 and with Zeiss-1000 1-m telescope of Tien Shan Astronomical 
Observatory starting on Feb. 20 (UT) 23:17:45. Within enhanced XRT
position of XRT afterglow (Burrows et al., GCN 27157) we detected an 
optical object in coordinates of (J2000) 17:30:02.275 +10:32:22.47 with 
uncertainities of 0.3 arcsec in both coordinates. Coordinates are 
consistent with possible host galaxy (Xu et al., GCN 27161) which is 
presented in  Pan-STARRS catalaog. Preliminary photometry of the object 
is following.

Date UT start t-T0 Filter Exp. OT Err UL(3sigma)   telesope
                         (mid, days) (s)
2020-02-20 21:21:45 0.90596 R 40*60 21.55 0.15 22.2 AZT-33IK
2020-02-20 23:17:45 0.99207 R 56*60 n/d   n/d  21.3 Z-1000

Photometry is based on the USNO-B2.0 nearby stars.
USNO-B1.0    R2
1005-0285285 17.74
1005-0285301 19.23
1005-0285213 19.99

The object is somewhat brighter than that presented in Pan-STARRS DR1, 
and we suggest this object is a candidate for the afterglow of GRB 200115A.