TITLE: GCN CIRCULAR NUMBER: 43868 SUBJECT: The EP-WXT trigger 01709258681 (EP260227a?): Las Cumbres follow-up observation of the optical counterpart DATE: 26/02/28 02:12:37 GMT FROM: Wenxiong Li at NAOC <liwenxiong1992@gmail.com> Wenxiong Li (NAOC), Iair Arcavi (TAU), Ido Keinan (TAU), Runduo Liang (NAOC), David Sand (U of Arizona) We observed the position of the EP-WXT trigger 01709258681 (EP260227a?) with a Las Cumbres 1m telescope at Siding Spring Observatory 2.6 hours after the Einstein Probe WXT trigger and again 4 hours after the trigger. We took 2x300s exposures in each visit in the broad optical w band. We find a rapidly fading source consistent with the position reported by Eyles-Ferris et al. (GCN 43867) and measure the following preliminary photometry calibrated to the r band: Epoch 1: MJD 61098.954 Mag 20.28 ± 0.09 Epoch 2: MJD 61099.011 Mag 21.08 ± 0.10 View this GCN Circular online at https://gcn.nasa.gov/circulars/43868. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...