GCN Circular 43887
Subject
EP260227a: SVOM/VT optical observation
Event
Date
2026-03-01T09:51:54Z (7 months ago)
From
Yinuo Ma <mayn@bao.ac.cn>
Via
Web form
Y. N. Ma, Z. H. Yao, H. L. Li, Y. L. Qiu, C. Wu, L. P. Xin, X. H. Han, Y. Xu, J. Wang, P. P. Zhang, 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 a Target of Opportunity observation of EP260227a detected by EP/WXT (Wang et al., GCN 43869). SVOM/VT began observing the field at 2026-02-28T07:20:51 UTC, 11.14 hours after the trigger, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously.
With X-band data available, the optical counterpart (Eyles-Ferris et al., GCN 43867; Li et al., GCN 43868; Fu et al., GCN 43873; Mandarakas et al., GCN 43874; Eyles-Ferris & Tanvir, GCN 43875; Malesani et al., GCN 43876; Eyles-Ferris et al., GCN 43877; Strausbaugh & Cucchiara, GCN 43879; Bochenek & Perley, GCN 43880; Gassert et al., GCN 43881; Gupta et al., GCN 43884) was detected in both VT_B and VT_R bands. The magnitudes are:
mid time (h) | exposure time (s) | band | mag (AB)
-------------|-------------------|------|--------------
11.362 | 38*50 | VT_B | 21.9+-0.1
11.313 | 31*50 | VT_R | 21.3+-0.1
Our photometry was not corrected for Galactic extinction.
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.