GCN Circular 23881

I. V. Sokolov (Terskol Peak Observatory), A. V. Sergeev (Terskol Peak
Observatory), A. S. Moskvitin (SAO RAS), V. B. Petkov (BNO INR RAS)
report on behalf of larger collaboration.

We observed the field of the GRB 190202A (Lien et al., GCNC #23830)
with the Zeiss-2000 telescope of Terskol Peak Observatory
on February, 3, 21:14:49--22:52:52 UT.

We detected the OT (Novichonok et al., GCNC #23831; Steeghs et al.,
GCNC #23833; Paul Kuin & A. Y. Lien, GCNC #23834; Cucchiara,
GCNC #23839; Paek et al., GCNC #23841; Malesani et al., GCNC #23842; Belkin
et al., 23843; Moskvitin & Spiridonova, GCNC #23844;
Brajesh Kumar et al., GCNC #23853; Moskvitin et al., GCNC #23870;
Xu et al., GCNC #23871) in the stacked 16 x 180 sec. R band image.

Preliminary brightness of OT is R = 21.92 +/- 0.17 (T-T0 = 1.850 d).
The calibrations is based on nearby SDSS stars, magnitudes converted
with the Lupton 2005 equations.