{
  "body": "L. P. Xin(NAOC), Y. G. Yang(HNU), C. WU(NAOC), Y. L. Qiu(NAOC), J. Wang(GXU/NAOC),    \n\nH. L. Li(NAOC),  C. Wu(NAOC),  E. W. Liang(GXU), X. H. Han(NAOC), X. M. Lu(NAOC),   \n\nR. S. Zhang(NAOC), Y. Xu(NAOC), Y.J . Xiao(NAOC), P. P. Zhang(NAOC), L. Lan(NAOC),   \n\nJ. Y. Wei(NAOC) on behalf of the SVOM/GWAC team:  \n\n  \n\nWe began to observe X-ray transient EP240420a (Zhang et all., GCN 36194) \n\ndetected by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission,\n\nwith GWAC-F50A telescope at Xinglong station, China, at 13:58:11 (UT), 20. April. 2024,    \n\nabout 1.9 hours after the burst.   \n\n\n\n\nThe weather was not good.  \n\n\n\n\nAfter stacking 100*100s seconds, the candidate reported (An et al., GCN 23602)or\n\nany other new sources were not detected within the errorbox of EP-FXT (Han et al., GCN 23603) \n\nin our stacked image  down to a limit magnitude of 19.5 mag \n\nin R band comparing to several nearby USNO B1.0 stars.  \n\n\n\n\nWe acknowledge the excellent support from observation assistant Yangtong ZhengandWenlongDong.\n\n\n\n\n",
  "createdOn": 1713685642772,
  "bibcode": "2024GCN.36206....1X",
  "eventId": "EP240420a",
  "submitter": "Liping Xin at NAOC, SVOM <xlp@nao.cas.cn>",
  "subject": "EP240420a:  GWAC-F50A optical upper limit",
  "submittedHow": "email-legacy",
  "circularId": 36206
}