GCN Circular 45847
EP261007b: Einstein Probe detection of an X-ray transient
From: EP Team at NAOC/CAS
Issued: 2026-10-08 03:02 UTC
Type: X-ray Transient
Why this event is posted: it has drawn 11 GCN Circulars, at or above the top-10% threshold of 11 for X-ray transients.

W.F. Wen (SZTU), L.N. Xu (USTC), H.Y. Liu (NAO, CAS), Q.H. Lao (NAO, CAS), X.H. Tang (THU) and C.C. Jin (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 EP261007b. The transient triggered EP-WXT (ID: 01709321008) at 2026-10-07T15:05:16(UTC). The WXT position of the source is R.A. = 356.349 deg, DEC = 11.369 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. = 356.3481 deg, DEC = 11.3539 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 are 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).

Filter: only the top 10% of the past year's X-ray transients are posted, ranked by the number of GCN Circulars written about them (now ≥ 11). Thresholds are recalculated monthly. Only events first reported within the past 7 days can start a thread.
Relayed automatically from NASA's General Coordinates Network.