TITLE: GCN CIRCULAR NUMBER: 36123 SUBJECT: GRB 240415A: optical afterglow detection from the INAF Asiago Observatory DATE: 24/04/15 21:17:04 GMT FROM: Paolo D'Avanzo at INAF-OAB A. Reguitti (INAF-OAB / INAF-OAPd), P. D'Avanzo (INAF-OAB), L. Tomasella (INAF -OAPd), E. Cappellaro (INAF -OAPd), report on behalf of the CIBO and of the GRAWITA collaborations: We carried out follow-up optical observations of GRB 240415A (Fermi GBM Team, GCN Circ. #36107; Moss et al., GCN Circ. #36108) from the INAF - Padova Astronomical Observatory located in Asiago (Italy) with the 67/92 Schmidt telescope starting on 2024-04-15 at 19:13:10 UT (~ 12.8 hours after the burst) with the r-sdss filter. In our stacked image the optical afterglow (Pankov et al., GCN Circ. #36118; Pankov et al., GCN Circ. #36121; Moskvitin et al., GCN Circ. #36122) is detected. From preliminary analysis we estimate a magnitude of r = 21.0 +/- 0.3 (AB; calibrated against r band of the PanSTARRS catalog). Further observations are ongoing.