TITLE: GCN CIRCULAR NUMBER: 45045 SUBJECT: EP260623a: TNG NIR afterglow detection DATE: 26/06/25 15:50:24 GMT FROM: Riccardo Brivio at INAF-OAB <riccardo.brivio@inaf.it> R. Brivio (INAF-OAB), M. Ferro (INAF-OAB), L. Izzo (INAF-OACN and DARK/NBI), D. B. Malesani (DAWN/NBI and Radboud), A. Melandri (INAF-OAR), V. Lorenzi (INAF-TNG), A. G. de Gurtubai Escudero (INAF-TNG) report on behalf of the CIBO collaboration: We observed the field of EP260623a detected by EP/WXT (Wang et al., GCN 45020) with the Italian 3.6m TNG telescope equipped with the near-infrared camera NICS to follow up its afterglow. A series of images were obtained with the K filter starting on 2026-06-25 at 01:29:13 UT (i.e. 1.94 days after the trigger). The afterglow (Li et al., GCN 45021; Izzo et al., GCN 45022; Angulo et al., GCN 45024; Brivio et al., GCN 45025; Jiang et al., GCN 45026; Li et al., GCN 45027; Jelinek et al., GCN 45029; Lee et al., GCN 45030; Saikia et al., GCN 45034; Bochenek & Perley, GCN 45040; Busmann et al., GCN 45042) is detected in the co-added image with a preliminary magnitude of K = 19.9 +/- 0.2 mag (Vega; calibrated against the 2MASS catalogue), at a mid-time of 1.96 days after the trigger. View this GCN Circular online at https://gcn.nasa.gov/circulars/45045. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...