TITLE:   GCN CIRCULAR
NUMBER:  46221
SUBJECT: GRB 261110A: LCO optical upper limits
DATE:    26/11/11 02:57:39 GMT
FROM:    SVOM_group <svomgroup@bao.ac.cn>

Y.Y. Shi (GXU), A. Saccardi, D. Turpin (CEA/Irfu), C. Wu, L.P. Xin (NAOC), S.J. Yin, Y.X. Guan (GXU),  W.Jun. Tan (PKU), J.X. Cao (GXU) report on behalf of the SVOM mission team:


We observed the field of GRB 261110A (SVOM burst-id sb26111002) detected by SVOM (Wang et al., GCN 46215) with the LCO 1m telescope at Cerro Tololo Inter-American Observatory equipped with the Sinistro instrument.

Our observation started on 2026-11-11T00:46:09 UTC (about 12.94 hr after the trigger) and we obtained 3x200 s exposures in the SDSS r and Pan-STARRS z filter.

We do not detect the optical counterpart (Wu et al., GCN 46218; Li et al., GCN 46219; Moskvitin et al., GCN 46220) in our stacked image. We measure the following upper limits calibrated against the Pan-STARRS DR1 catalog, and not corrected for Galactic extinction:

r > 22.3 AB (3-sigma, mid-time 13.03 hr after the trigger),
z > 20.2 AB (3-sigma, mid-time 13.07 hr after the trigger).

This project is funded by the SVOM collaboration.