GCN Circular 36124
Subject
GRB 240415A: OHP/T193 optical observations
Date
2024-04-15T22:12:13Z (23 days ago)
From
Benjamin Schneider at MIT <bschn@mit.edu>
Via
Web form
B. Schneider (MIT), C. Adami, O. Ilbert, N. A. Rakotondrainibe (LAM/Pytheas/AMU), D. Turpin, E. Le Floc’h (CEA Paris-Saclay), A. Saccardi, S. Vergani (GEPI/Obs. de Paris) report on behalf of a larger collaboration:
We observed the field of the GRB 240415A (Fermi GBM team, GCN 36107; Moss et al., GCN 36108; Evans et al., GCN 36109) and its afterglow candidate (Pankov et al., GCN 36118, GCN 36121; Moskvitin et al., GCN 36122; Reguitti et al., GCN 36123) using the T193cm telescope at Observatoire de Haute-Provence (France) equipped with the MISTRAL spectro-imager. A total of 6 exposures (5x600s + 1x480s) were obtained in the r-band at 20:37:17.5 UT on 2024-04-15 (~14.1h after the trigger). In the combined frame, we clearly detect the optical afterglow and measure the following preliminary magnitude:
r = 21.67 +/- 0.10 mag (AB)
The photometric calibration was performed using nearby stars from the PanSTARRS catalog and the magnitude is not corrected for Galactic extinction.
We acknowledge the excellent support from Observatoire de Haute-Provence and in particular Jean Balcaen for the MISTRAL observations.