GCN Circular 22169
A. Volnova (IKI), A. Kusakin (Fesenkov Astrophysical Institute), I. Reva (Fesenkov Astrophysical Institute), E. Mazaeva (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 171123A (Evans et al., GCN 22148) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on Nov., 23 (UT) 23:31:56. We took several images in R-filter. Within enhanced XRT error circle (Goad et al., GCN 22150) we do not detect any object. Preliminary photometry of the afterglow is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) (3 sigma) 2017-11-23 23:31:56 0.41294 R 38*120 n/d n/d 22.2 Photometry is based on nearby USNO-B1.0 stars, R2 magnitude.