TITLE: GCN CIRCULAR NUMBER: 43750 SUBJECT: EP260214b: LCO optical counterpart detection DATE: 26/02/15 11:37:27 GMT FROM: Ismael Perez-Fournon at Instituto de Astrofisica de Canarias <ipf@iac.es> I. Pérez-Fournon (IAC and ULL), F. Poidevin (IAC and ULL), D. Cano-Morales, A.E. Hernández-Díaz, I. Correa-Plasencia, E. Lekaroz-Urriza, M. Quintana-Ansaldo (all ULL), A. López-Oramas (IAC and ULL), and D. Aguado (IAC and ULL) Following the detection of the fast X-ray transient EP260214b (Yang et al., GCN #43744), we observed the field with one of the two Las Cumbres Observatory (LCO) 1-m telescopes located at the LCO node at McDonald Observatory, Texas. The observation consisted of a single exposure of 500 sec in the SDSS r' filter, that started on 2026-02-15 at 09:24:15 UT, about 11.34 hours after the EP trigger. The optical counterpart detected by He et al. (GCN #43745) and Watson et al. (GCN #43747) at a resdhift z = 1.208 (Le Floch et al., GCN #43749) is clearly detected in our image with an AB magnitude of r' = 21.28 +/- 0.09, calibrated against PanSTARRS-1 DR2 stars and not corrected for Galactic extinction. This work makes use of observations from the Las Cumbres Observatory global telescope network (LCO program IAC2026A-011, SGLF and Superluminous Supernovae surveys). This work made use of the Astro-COLIBRI platform (P. Reichherzer et al. 2021, ApJS, 256, 5). View this GCN Circular online at https://gcn.nasa.gov/circulars/43750. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...