TITLE: GCN CIRCULAR NUMBER: 43375 SUBJECT: EP260110a: SVOM/VT optical upper limits DATE: 26/01/12 04:40:42 GMT FROM: Huali Li at at NAOC, SVOM <lhl@nao.cas.cn> H. L. Li, L. P. Xin, Y. L. Qiu, C. Wu, Y. N. Ma, Z. H. Yao, X. H. Han, J. Wang, P. P. Zhang, Y. Xu, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. R. Xu, J. S. Deng, J. Y. Wei (NAOC), J. Palmerio (CEA) report on behalf of the SVOM/VT team. SVOM/VT performed ToO observation on the fast X-ray transient EP260110a (Zhang et al., GCN 43363; 43367). The observation started on 2026-01-10T14:29:11 UT (i.e. 2.52 hour post trigger) in VT_B (400nm-650nm) and VT_R (650nm-1000nm) channel simultaneously. Inside the error box of the EP-FXT (Zhang et al., GCN 43367) we did not detect any new uncatalogued source, which was consistent with the non detections reported by other groups (Perez-Garcia et al., GCN 43364; Kang et al., GCN 43365; Antier et al., GCN 43366; Zheng et al., GCN 43368; Lipunov et al., GCN 43372). The 3 sigma limits in AB magnitude are derived as below: Mid time | Band | Exposure Time | 3 sigma limit magnitude 4.11 hour VT_B 52*70 sec > 23.5 4.64 hour VT_R 50*70 sec > 23.5 The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. VT was jointly developed by Xi'an Institute of Optics and Precision Mechanics (XIOPM), CAS and National astronomical observatories (NAOC), CAS. View this GCN Circular online at https://gcn.nasa.gov/circulars/43375. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...