TITLE: GCN CIRCULAR NUMBER: 35619 SUBJECT: GRB 240123A: SAO RAS optical observations DATE: 24/01/24 11:10:25 GMT FROM: Moskvitin Alexander at SAO RAS <mosk@sao.ru> A. S. Moskvitin, O. A. Maslennikova, O. I. Spiridonova (SAO RAS) report on behalf of the GRB follow-up team. We observed the field of GRB 240123A (D'Ai et al., GCN #35602; Scotton, GCN #35610) with the 1-m telescope of SAO RAS equipped with the CCD photometer. We obtained 12 x 300 sec. images in Rc band on Jan 24, 02:15:54 -- 03:42:02 UT (t_mid - T0 = 0.66194 days). The OT (D'Ai et al., GCN #35602; Pankov et al., GCNs #35605, #35609; Sasada et al., GCN #35618) is clearly detected in our stacked frame with the brightness of R = 21.12 +/- 0.09. The photometry is based on R2 magnitudes of nearby USNO-B1 stars. View this GCN Circular online at https://gcn.nasa.gov/circulars/35619. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...