TITLE: GCN CIRCULAR NUMBER: 40401 SUBJECT: EP250508a: KAIT optical upper limit DATE: 25/05/08 18:38:55 GMT FROM: Weikang Zheng at UC Berkeley <weikang@berkeley.edu> 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 EP250508a (Liang et al., GCN 40390) starting at 06:17, May 08 UT, about 14 minutes after the burst. A set of clear (roughly R) filter images were obtained. Preliminary analysis do not reveal any new optical counterpart candidate within the X-ray afterglow error circles (Liang et al., GCN 40390; Zhao et al., GCN 40399). Due to the bright moonlight, our image quality are degraded and we estimate the limiting magnitude of our single image to be ~17.0 mag, shallower than the upper limit reported by other groups (Ugarte Postigo et al., GCN 40391; Lipunov et al., GCN 40393; Brivio et al., GCN 40395). View this GCN Circular online at https://gcn.nasa.gov/circulars/40401. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...