TITLE:   GCN CIRCULAR
NUMBER:  43681
SUBJECT: EP260210a: Einstein Probe detection of an X-ray transient
DATE:    26/02/10 12:13:39 GMT
FROM:    EP Team at NAOC/CAS <ep_ta@bao.ac.cn>

R. Shi (PMO), Z. H. Yang, Q. C. Zhao (IHEP), G. Y. Zhao (SYSU), Y. J. Zhang (THU) and Z. X. Ling (NAOC) 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 EP260210a. The transient triggered EP-WXT (ID: 01709257873) at 2026-02-10T10:23:01 (UTC). The WXT position of the source is R.A. = 169.840 deg, DEC = 45.408 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. = 169.8314 deg, DEC = 45.3949 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).