GCN Circular 39525
Subject
EP250228a: Einstein Probe detection of an X-ray transient
Date
2025-02-28T07:09:00Z (9 days ago)
From
EP Team at NAOC/CAS <ep_ta@bao.ac.cn>
Via
Web form
H.Y. Liu (NAO, CAS), J.Q. Peng (IHEP, CAS), W. F. Wen(SZTU), J. H. Wu (GZHU), C.C. Jin (NAO, CAS) report on behalf of the Einstein Probe team:
We 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 EP250228a. The transient triggered EP-WXT (ID: 01709132122) at 2025-02-28T03:59:09 (UTC). The WXT position of the source is R.A. = 103.607 deg, DEC = -41.581 deg (J2000) with an uncertainty of 3 arcmin in radius (90% C.L. statistical and systematic).
A 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. = 103.6021 deg, DEC = -41.5715 deg (J2000) with an uncertainty of 20 arcsec in radius (90% C.L. statistical and systematic).
Further information will be updated when the telemetry data is received.
Launched 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).