TITLE: GCN CIRCULAR NUMBER: 37401 SUBJECT: GRB 240905E: SAO RAS optical upper limit DATE: 24/09/05 21:26:52 GMT FROM: Moskvitin Alexander at SAO RAS A. S. Moskvitin and O. I. Spiridonova (SAO RAS) report on behalf of the GRB follow-up team. We observed the field of GRB 240905E (Dichiara et al., GCN 37397) using SAO RAS 1-meter telescope Zeiss-1000 equipped with the New CCD-photometer. The observations started 2024-09-05T18:50:23, 24.3 min after the Swift trigger. We obtained 10 x 60 + 4 x 300 sec. images in Rc band (t_mid - T0 = 0.69 hours). Within the XRT error circle (Dichiara et al., GCN 37397) we did not detect any source down to a limiting magnitude of R_lim = 22.8 calibrated against nearby Pan-STARRS stars (magnitudes converted to R band) and not corrected for the MW extinction.