GCN Circular 42571
Subject
GRB 251103A: KAIT optical observations
Event
Date
2025-11-04T08:07:10Z (a day ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
Via
email
WeiKang Zheng (UCB), Xuhui Han (NAOC), Pinpin Zhang (NAOC) 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 251103A (Hu et al.,
GCN 42534; Fermi GBM Team, GCN 42536; Wang et al., GCN 42552;
Sonawane et al., GCN 42553; DeLaunay et al., GCN 42568) starting
at 11:54 UT, 7.13 hours after the burst. A set of clear (roughly R)
filter images were obtained. We clearly detected the afterglow
(Schneider et al., GCN 42535; Turpin et al., GCN 42538; Gritsevich
et al., GCN 42539; Izzo et al., GCN 42540; O'Neill et al., GCN 42543;
Ghosh et al., GCN 42545; Schneider et al., GCN 42549; Breeveld et al.,
GCN 42554; Hellot et al., GCN 42559; Mo et al., GCN 42562) in our
coadd image. We measure its brightness to be 19.4 +/- 0.2 mag (Vega)
at mid time of 7.72 hours after the burst.