{
  "bibcode": "2026GCN.43799....1M",
  "body": "Min-He (NAOC),  Junjie-Jin (NAOC), Haiyang-Mu (NAOC), Feng-Xiao (NAOC), Pengliang-Du (NAOC), Zhou-Fan (NAOC), Hong-Wu (NAOC) report on behalf of a large collaboration:\n\nFollowing the detection of EP-WXT01709258519, we observed the field of EP-WXT01709258519 ( +11:05:00.96 +38:12:32.40 ) using the 2.16-m telescope at Xinglong Observatory, NAOC. We obtained 3x300s clear-band frames with a median time of 2026-02-21T19:28:39, 11 hr after the EP trigger.\n\nNo uncatalogued optical transient is detected in the stacked images within the 3 arcmin EP/WXT error circle (WXT01709258519), down to 3-sigma limiting magnitudes of 21.01 mag for 2.16-m, calibrated with Pan-STARRS sources in the field. Also there is no apparent brightening for the catalogued sources within the error circle.",
  "circularId": 43799,
  "subject": "EP-WXT01709258519: Xinglong optical upper limit",
  "submitter": "Xinglong Observatory at National Astronomical Observatories (NAOC), Chinese Academy of Sciences (CAS) <xinglong@nao.cas.cn>",
  "format": "text/plain",
  "submittedHow": "web",
  "createdOn": 1771709115053
}