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). View this GCN Circular online at https://gcn.nasa.gov/circulars/41956. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...