TITLE: GCN CIRCULAR NUMBER: 43616 SUBJECT: GRB 260204A: LCO optical upper limits DATE: 26/02/04 21:16:28 GMT FROM: SVOM_group <svomgroup@bao.ac.cn> D. Turpin (CEA/Irfu), A. Saccardi (CEA/Irfu), D. B. Malesani (DAWN/NBI and Radboud), B. Cordier (CEA/Irfu), report on behalf of the SVOM mission team: We observed the field of GRB 260204A (Pillas et al., GCN 43613) with the LCO 1-m telescope at Siding Spring Observatory equipped with the Sinistro instrument. Our observation started on 2026-02-04 at 15:10:42 UT (about 22 min after the trigger) and we obtained 3x200 s in each of the SDSS r and Pan-STARRS z filters. In the stacked image, we do not detect any new source within the SVOM/ECLAIRs error box. We measure the following upper limit calibrated against the PanSTARRS DR1 catalog, and not corrected for Galactic extinction: r > 20.3 AB (5-sigma, mid-time 25.7 min after the trigger); z > 19.4 AB (5-sigma, mid-time 38.4 min after the trigger). This project is funded by the SVOM collaboration. View this GCN Circular online at https://gcn.nasa.gov/circulars/43616. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...