GCN Circular 40550
Subject
EP250526a: Einstein Probe detection of a fast X-ray transient
Date
2025-05-27T03:02:34Z (3 days ago)
From
EP Team at NAOC/CAS <ep_ta@bao.ac.cn>
Via
Web form
D. Y. Li (NAO, CAS), B.-T. Wang (YNAO, CAS), W. F. Wen (SZTU), J. H. Wu (GZHU), Y. Liu (NAO, CAS) on behalf of the Einstein Probe (EP) team:
We report on the detection of a fast X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP250526a. The transient triggered EP-WXT (ID: 01709176979) at 2025-05-26 19:28:23 (UTC). The WXT position of the source is R.A. = 217.049 deg, DEC = -34.355 deg (J2000) with an uncertainty of 2.9 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 circle, an uncatalogued X-ray source was detected at R.A. = 217.0509 deg, DEC = -34.3293 deg (J2000) with an uncertainty of 10 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).