GCN Circular 41754
Subject
EP250908c: Einstein Probe detection of an X-ray transient
Event
Date
2025-09-09T02:45:12Z (4 days ago)
From
EP Team at NAOC/CAS <ep_ta@bao.ac.cn>
Via
Web form
M. H. Zhang, M. J. Liu (NAO, CAS), Y.-H. I. Yin (NJU), X. X. Sun, T. Y. Liu, H. Y. Ren, H. Sun (NAO, CAS) on behalf of the Einstein Probe (EP) 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 EP250908c. The transient triggered EP-WXT (ID: 01709240659) at 2025-09-08T23:50:54 (UTC). The WXT position of the source is R.A. = 8.226 deg, DEC = -50.447 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 circle, an uncatalogued X-ray source was detected at R.A. = 8.2170 deg, DEC = -50.4633 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).