TITLE: GCN CIRCULAR NUMBER: 38746 SUBJECT: GRB 241229B: Continued CrAO ZTSh observations DATE: 24/12/31 23:03:47 GMT FROM: Alexei Pozanenko at IKI, Moscow <grb.alex@gmail.com> N. Pankov (HSE, IKI), A. Volnova (IKI), A. Pozanenko (IKI), V. Rumyantsev (CrAO), report on behalf of the IKI-GRB-FuN collaboration: We observed the field of GRB 241229B (Fermi GBM Team, GCN 38698; D'Ai et al., GCN 38699) with 2.6-meter ZTSh telescope of CrAO. The observations started on 2024-12-30 (UT) 18:30, i.e. ~1.73 days since GBM trigger. The series of 30x120 s images were obtained using the CCD-photometer. The optical counterpart (SVOM/VT team, GCN 38729; Volnova et. al, GCN 38732) has been detected in a stacked image. Preliminary photometry is the following: Date UTstart T-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) 2024-12-30 18:13:33 1.73423 30x120 R 23.40 0.15 24.0 The photometry has been calibrated against nearby PS1 stars (see Volnova et. al, GCN 38732). View this GCN Circular online at https://gcn.nasa.gov/circulars/38746. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...