TITLE: GCN CIRCULAR NUMBER: 40895 SUBJECT: GRB 250702F: Ondrejov D50 optical afterglow detection DATE: 25/07/02 21:46:43 GMT FROM: Martin Jelinek at Astro.Inst-AVCR,Ondrejov <martin.jelinek@asu.cas.cz> M. Jelinek, F. Novotny, A. Malenakova, J. Strobl, R. Hudec, C. Polasek (ASU CAS Ondrejov) report:We are observing the position of the Swift-detected GRB 250702F (trigger #1329888, very likely identical to Fermi GBM trigger #773183208) with the D50 robotic telescope of the Astronomical Institute Ondrejov, near Prague, Czech Republic. We initially performed a series of 20s unfiltered exposures starting 27.8s after the Swift trigger. We clearly detect a possible optical afterglow in single 20s images at 14:11:44.6s +16:44:55 (J2000, 212.935979, +16.748483). The forward shock component peaked at unfiltered magnitude ~15.1 approximately 4 minutes post-GRB and shows a slow decay during our ongoing observations. Further observations and detailed photometry are in progress. View this GCN Circular online at https://gcn.nasa.gov/circulars/40895. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...