GCN Circular 45838
Y.Y. Shi(GXU), Z. Kang (CHO),S.J. Yin (GXU), C. Wu (NAOC), L.P. Xin, X.H. Han, P.P. Zhang, X.M. Lu (NAOC), Z.W. Li, Y. Lv (CHO), R.S. Zhang, Y.J. Xiao, Y.L. Qiu, J. Wang, J.S. Deng, L. Huang, J.Y. Wei (NAOC), W.L. Zhang(PMO), X. Tian(GXU) report on behalf of the SVOM/C-GFT team:
We observed the field of GRB 261007A detected by SVOM/ECLAIRs (Goto et al., GCN 45824) with LATIOS on SVOM/C-GFT. Observations started at 2026-10-07T12:54:31 UTC, ~7.21 hr after the trigger.
The optical candidate (Zheng et al., GCN 45825; Saccardi et al., GCN 45829; Mohan et al., GCN 45832; Saccardi et al., GCN 45837) was faintly detected in our stacked images of band g, r and i. The magnitude is:
| [date-obs(mid-time)] | Mid_t-T0(h) | exposure time (s) | band | mag (AB) | mag_err |
|---|---|---|---|---|---|
| 2026-10-07T13:46:09 | 8.07 | 19×100s | g | 20.35 | +/- 0.20 |
| 2026-10-07T14:02:59 | 8.35 | 20×100s | r | 20.26 | +/- 0.23 |
| 2026-10-07T13:28:38 | 7.78 | 19×100s | i | 19.93 | +/- 0.15 |
The photometry was calibrated against DESI Legacy Imaging Surveys DR10 catalogue and no correction for Galactic dust extinction was applied.
We thank the observation assistants B.-W. Li and H.-X. Xue at Jilin observatory for their excellent support.
The Chinese Ground Follow-up Telescope (C-GFT) for the SVOM mission is located at Jilin Station, Changchun Observatory, National Astronomical Observatories, CAS. It features two instruments: (1) CATCH at the Cassegrain focus with a 21 arcmin x 21 arcmin FOV for simultaneous g/r/i-band imaging, and (2) LATIOS, a 4k x 4k CMOS camera at the prime focus with a 1.28 deg x 1.28 deg FOV that images in g, r, and i bands via filter switching.