TITLE: GCN CIRCULAR NUMBER: 42389 SUBJECT: EP251023a: GSP Optical Counterpart Detection DATE: 25/10/23 09:13:54 GMT FROM: Wenxiong Li at NAOC W. X. Li, S. J. Xue (NAOC); M. Andrews, J. Farah, D. A. Howell, M. Newsome, E. Padilla Gonzalez, C. McCully, and G. Terreran (Las Cumbres Observatory), on behalf of a larger collaboration, report optical follow-up observations of EP251023a (Wu et al. GCN 42388) obtained with a Las Cumbres Observatory (LCO) 1-m telescope at Teide Observatory, Tenerife, ~3.6 hours after the EP-WXT trigger. We acquired 2 × 300 s exposures using the broad optical w band. The optical counterpart reported by Wortley et al. (GCN 42387) is detected. Preliminary photometry, calibrated to the r band, yields r ≈ 18.5 mag (not corrected for Galactic extinction). No known source is found at this position in the MPC or other major catalogs. These observations were taken as part of the Global Supernova Project (GSP).