{
  "circularId": 41761,
  "submitter": "Yinuo Ma <mayn@bao.ac.cn>",
  "body": "Y. N. Ma, Z. H. Yao, L. P. Xin, Y. L. Qiu, C. Wu, H. L. Li, X. H. Han, Y. Xu, J. Wang, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. S. Deng, J. Y. Wei (NAOC), J. Palmerio (CEA) report on behalf of the SVOM/VT team. \n\nSVOM performed a Target of Opportunity observation of EP250908c detected by EP/WXT (Zhang et al., GCN 41754). SVOM/VT began observing the field at 2025-09-09T00:29:02 UTC, 0.636 hours after the trigger, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. \n\nWith X-band data availible, the optical counterpart (Malesani et al., GCN 41760) was clearly detected in both VT_B and VT_R. The magnitudes are:\n\nmid time (h) | exposure time (s) | band | mag (AB) | mag err\n-------------|-------------------|------|----------|--------\n    0.987    |      16*50        | VT_B |  20.73   |  0.05 \n    0.987    |      15*50        | VT_R |  19.76   |  0.04 \n\nOur photometry was not corrected for Galactic extinction.\n\nThe 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.\n",
  "eventId": "EP250908c",
  "bibcode": "2025GCN.41761....1M",
  "submittedHow": "web",
  "format": "text/plain",
  "subject": "EP250908c: SVOM/VT optical observation",
  "createdOn": 1757395373727
}