TITLE: GCN CIRCULAR NUMBER: 37000 SUBJECT: EP240801a: KAIT optical counterpart observations DATE: 24/08/01 17:41:44 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, automatically responded to the fast X-ray transient EP240801a from the Einstein Probe (Zhou et al. GCNC 36997) starting at 09:27 UT, ~0.41 hours after the trigger. A set of clear (roughly R) filter images were obtained. The optical counterpart reported by Fu et al. (GCN 36998) and Li et al. (GCN 36999) was clearly detected in our coadded images. The preliminary photometry results are shown below calibrated to the PS1 catalog: Tmid-T0(hr) exp(s) Mag err 0.41 6x20s 19.86 0.07 0.54 6x40s 20.02 0.05 0.73 5x60s 20.05 0.04 0.93 5x60s 20.11 0.07 1.54 7x60s 20.17 0.06 1.93 9x60s 20.09 0.06 View this GCN Circular online at https://gcn.nasa.gov/circulars/37000. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...