TITLE: GCN CIRCULAR NUMBER: 43905 SUBJECT: EP260227a: Gemini-South optical observations DATE: 26/03/03 10:58:44 GMT FROM: Laura Cotter at University College Dublin <laura.cotter@ucdconnect.ie> R. A. J. Eyles-Ferris (Leicester), J. Quirola-Vasquez (Radboud), G. Corcoran (UCD), A. Martin-Carrillo (UCD), P. G. Jonker (Radboud), , A. J. Levan (Radboud), D. B. Malesani (DAWN/NBI and Radboud) report on behalf of a larger collaboration: We observed the optical counterpart of the fast X-ray transient EP260227a (Wang et al., GCN 43869) with the Gemini-South telescope equipped with the GMOS-S instrument, obtained 12x60 s exposures in the r band starting at 2026-03-03 05:52:34 UT (t_mid = 81.9 hr). In our stacked image, we detect a faint source coincident with the optical counterpart (Eyles-Ferris et al., GCN 43867; Li et al., GCN 43868; Fu et al, GCN 43873; Mandarakas et al., GCN 43874; Eyles-Ferris and Tanvir et al., GCN 43875; Malesani et al., GCN 43876; Eyles-Ferris et al., GCN 43877; Strausbaugh et al., GCN 43879; Bochenek et al., GCN 43880; Gassert et al., GCN 43881; Gupta et al., GCN 43884; Ma et al., GCN 43887; Eyles-Ferris et al., GCN 43888; Zhong et al., GCN 43891; Volnova et al., GCN 43894). In our preliminary photometry, we measure an AB magnitude of r = 24.80 +/- 0.33 calibrated to Pan-STARRS and not corrected for Galactic extinction. It is unclear at this stage whether this is continued transient emission or the underlying host galaxy. View this GCN Circular online at https://gcn.nasa.gov/circulars/43905. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...