TITLE: GCN CIRCULAR NUMBER: 43303 SUBJECT: GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations DATE: 26/01/02 14:09:15 GMT FROM: Dalya Akl at New York University Abu Dhabi <dka2010@nyu.edu> Sarah Antier (IJCLAB), William H. Lee (UNAM), Dalya Akl (NYUAD), Alan M. Watson (UNAM), Stéphane Basa (UAR Pytheas), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Rosa L. Becerra (UNAM), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Nikos Mandarakas (LAM), Kin Ocelotl López (UNAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sánchez Álvarez (UNAM), Benjamin Schneider (LAM), Antonio de Ugarte Postigo (LAM), Wenjin Xie (NAOC), and Wenjun Tan (IHEP) report: We imaged the field of the SVOM GRB 260102A (Xie et al., GCN Circ. 43295) using the DDRAGO wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2026-01-02 13:04 to 13:25 UTC (about 8.9 hours after the trigger) and obtained 18 minutes of simultaneous exposure in the r/z filters. The data were reduced and coadded with the COLIBRÍ ASU pipeline and analyzed with STDWeb/STDPipe (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. We did not detect the optical counterpart reported by Wu et al. (GCN Circ. 43300) to preliminary 3-sigma magnitude limits of: r > 23.5 z > 22.8 We thank the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir and the COLIBRÍ and DDRAGO engineering teams. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico. View this GCN Circular online at https://gcn.nasa.gov/circulars/43303. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...