{
  "subject": "EP250223a: Einstein Probe detection of an X-ray transient",
  "submitter": "EP Team at NAOC/CAS <ep_ta@bao.ac.cn>",
  "format": "text/plain",
  "bibcode": "2025GCN.39429....1L",
  "eventId": "EP250223a",
  "circularId": 39429,
  "submittedHow": "web",
  "createdOn": 1740327763987,
  "body": "T. Y. Lian, W. J. Zhang (NAOC, CAS), Y. Wang (PMO, CAS), X. Tian (GXU), R. Z. Li(YNAO, CAS), H. W. Pan (NAOC, CAS) report on behalf of the Einstein Probe team:\n \nWe report on the detection of an X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP250223a. The transient triggered EP-WXT (ID: 01709131863) at 2025-02-23T15:04:35.749 (UTC). The WXT position of the source is R.A. = 98.258 deg, DEC = -22.432 deg (J2000) with an uncertainty of 3 arcmin in radius (90% C.L. statistical and systematic). \n\nA follow-up observation with the Follow-up X-ray Telescope (FXT) was performed automatically. Within the WXT error cirlce, an uncatalogued X-ray source was detected at R.A. = 98.2722 deg, DEC = -22.4442 deg (J2000) with an uncertainty of 20 arcsec in radius (90% C.L. statistical and systematic).\n\nFurther information will be updated when the telemetry data is received.\n\nLaunched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics)."
}