GCN Circular 41956
Subject
GRB 250920C: KAIT optical observations
Event
Date
2025-09-23T18:23:18Z (21 hours ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
Via
email
WeiKang Zheng (UCB) and Alexei V. Filippenko (UCB) report on
behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, observed the field of GRB 250920C (Fermi GBM
team, GCN 41903; Gupta et al., GCN 41904; Mailyan et al., GCN 41917;
Gupta et al., GCN 41924; SVOM Team, GCN 41929) around mid time of
~0.778d after the burst. A set of 90x60s clear (roughly R) filter
images were obtained. We marginally detected the optical afterglow
(Wortley et al., GCN 41907; Strausbaugh et al., GCN 41911; Ghosh
et al., GCN 41913; Lipunov et al., GCN 41916; Kuin et al., GCN 41920;
Mohan et al., GCN 41925; Sanchez-Ramirez et al., GCN 41928;
Guiffreda et al., GCN 41943; de Ugarte Postigo et al., GCN 41951).
We estimate the afterglow to be 21.0 +/- 0.3 mag (Vega).