TITLE: GCN CIRCULAR NUMBER: 44341 SUBJECT: EP260416a: Ondrejov D50 optical detection DATE: 26/04/18 19:52:07 GMT FROM: Martin Jelinek at Astro.Inst-AVCR,Ondrejov <martin.jelinek@asu.cas.cz> M. Jelinek, J. Strobl, F. Novotny, A. Malenakova and R. Hudec (ASU CAS Ondrejov, CZ) report: We observed the field of EP260416a (Hu et al., GCN 44307) with the 50 cm robotic telescope (D50) of the Astronomical Institute Ondrejov, near Prague, Czech Republic. We obtained a series of 120 s Sloan-r band exposures starting at 20:09 UT on 2026 April 17, i.e. 38.66 h after the initial trigger, and combined 68 frames with a mean exposure time of 40.03 h after the trigger. The optical counterpart (Ducoin et al., GCN 44310; Li et al., GCN 44315; Hua et al., GCN 44318; Lee et al., GCN 44319; Zheng et al., GCN 44321; Martin-Carrillo et al., GCN 44328; Li et al., GCN 44334) is detected in the combined image. The preliminary AB magnitude of the object is r = 21.08 +/- 0.23, calibrated against the ATLAS catalog and not corrected for Galactic extinction. Our measurement is consistent with the continued fading of the afterglow. View this GCN Circular online at https://gcn.nasa.gov/circulars/44341. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...