GCN Circular 45884
Subject
EP261010a: SVOM/VT optical upper limits
Event
Date
2026-10-10T12:25:59Z (2 days ago)
From
Yinuo Ma <mayn@bao.ac.cn>
Via
Web form
Y. N. Ma, H. L. Li, L. P. Xin, Y. L. Qiu, C. Wu, Z. H. Yao, J. R. Xu, L. J. Chen, X. H. Han, Y. Xu, J. Wang, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, J. S. Deng, J. Y. Wei (NAOC), J. Palmerio (CEA) report on behalf of the SVOM/VT team.
SVOM/VT performed a Target of Opportunity observation of EP261010a detected by EP/WXT (Li et al., GCN 45880). SVOM/VT began observing the field at 2026-10-10T02:20:41 UTC, 2.033 hours after the trigger, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously.
No uncatalogued candidate was identified in our stacked images within the error box provided by EP/FXT position (Li et al., GCN 45880), compared to the Legacy Survey.
The following measurements are in AB magnitudes and are not corrected for Galactic extinction:
Mid time | Band | Exposure Time | 3-sigma upper limit
3.21 hr | VT_B | 44*50 s | > 23.4 mag
2.99 hr | VT_R | 33*50 s | > 23.1 mag
Our results are consistent with MASTER and NOT (Buckley et al., GCN 45881; Zhu et al., GCN 45882).
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.