TITLE:   GCN CIRCULAR
NUMBER:  41956
SUBJECT: GRB 250920C: KAIT optical observations
DATE:    25/09/23 18:23:18 GMT
FROM:    Weikang Zheng at UC Berkeley <weikang@berkeley.edu>

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).