GCN Circular 37615

Q. C. Shui (IHEP, CAS), D. Y. Li (NAOC, CAS), C. Zhou (HUST), G. Y. Zhao (SYSU), T. C. Zheng (PMO, CAS), and W. Yuan (NAOC, CAS) on behalf of the Eintein Probe team

The Follow-up X-ray Telescope (FXT) on board the Einstein Probe (EP) mission performed an autonomous observation on the X-ray transient detected by EP-WXT (trigger ID 01709061302). The observation started at 2024-09-27 01:08:38.0 (UTC), about 5 minutes after the EP-WXT trigger time. The FXT onboard data processing system detected a source at R.A. = 350.5437 deg, DEC = -3.0283 deg (J2000) with an uncertainty of about 20 arcsec (radius, 90% C.L. statistical and systematic), consistent with the position of the WXT transient within the uncertainties. The FXT source is associated with a K-type star, PM J23221-0301, at a distance of about 46 pc and located about 8 arcsec away from the FXT position. We suggest that this X-ray transient is likely a stellar flare event.

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).