TITLE: GCN CIRCULAR NUMBER: 37055 SUBJECT: GRB 240805B: BTA optical afterglow candidate DATE: 24/08/06 00:45:23 GMT FROM: Moskvitin Alexander at SAO RAS <mosk@sao.ru> A. Moskvitin, D. Oparin, A Vinokurov (SAO RAS), N. Pankov (HSE, IKI) and A. Pozanenko (IKI) report: We observed the field of the GRB 240805B (Williams et al., GCN 37043) with the BTA 6-meter telescope of SAO RAS equipped with the focal reducer Scorpio-I. We obtained 7 x 120 + 30 sec images on August 5, 2024-08-05T19:31:44 -- 2024-08-05T20:10:44 (t_mid - T0 = 8.372 hours). Within the enhanced XRT error circle (Goad et al., GCN 37053) close to its edge we detected a single source with the coordinates (J2000): R. A. = 16:56:51.20 Dec. = +18:19:11.7 +/- 0".5 and brightness of R = 21.62 +/- 0.04 (calibrated against nearby SDSS stars, magnitudes converted with Lupton 2005 equations) and not corrected for Galactic extinction. This source is located near SDSS object J165651.21+181914.0 but significantly brighter, thus it may be GRB OT. View this GCN Circular online at https://gcn.nasa.gov/circulars/37055. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...