GCN Circular 46257
Subject
GRB 261113A: OHP/T193 optical detections of the afterglow
Event
Date
2026-11-13T20:16:05Z (a day ago)
From
Christophe Adami at LAM <christophe.adami@lam.fr>
Via
Web form
C. Adami (LAM/Pytheas/AMU), B. Schneider (LAM), E. Le Floc’h (CEA/IRFU/DAp), S. Basa (LAM/OHP/Pytheas/AMU), report on behalf of the MISTRAL-GRB collaboration.
We observed the field of the SVOM/ECLAIRs GRB 261113A (Saccardi et al., GCN 46244) with the 1.93-m T193 telescope at the Observatoire de Haute-Provence (France), equipped with the MISTRAL spectro-imager.
We obtained 19 min, 30 min and 40 min of total integration times in the r, z, and g bands respectively, at mid-observing times of 2026-11-13 18:22UT, 2026-11-13 18:38UT and 2026-11-13 18:55UT.
In the preliminary stacked images, we detect in g, r and z bands the afterglow at the position of Gress et al. (GCN 46246), Lin et al. (GCN 46247), Lei et al. (GCN 46248), Li et al. (GCN 46249), Yin et al. (GCN 46250), Chen et al. (GCN 46251), Wu et al. (GCN 46252), Zhao et al. (GCN 46253), Li et al. (GCN 46254) and Saikia et al. (GCN 46256) with preliminary magnitudes of:
g = 22.08 +/- 0.21
r = 20.47 +/- 0.08
z = 20.16 +/- 0.08
The photometric calibration was performed using nearby stars from the Legacy Survey DR10 catalog (Dey et al. 2019) and the magnitudes are not corrected for Galactic extinction.
We acknowledge the excellent support from the Observatoire de Haute-Provence and in particular J. Balcaen. We also thank the SOPHIE observer: Neda Heidari.