General information
EP260731a is an Einstein Probe X-ray transient detected by WXT at 2026-07-31T00:54:24 UTC, with an uncatalogued FXT X-ray source subsequently found at R.A. 344.4279 deg, Dec. -11.7623 deg. The event has prompt optical follow-up but no reported optical counterpart.
Wavelength coverage
- X-ray: EP-WXT triggered on the transient, and EP-FXT detected an uncatalogued X-ray source within the WXT error circle.
- Optical: NOT/ALFOSC z-band imaging at 2.37 hr post-trigger found no uncatalogued transient to z ~ 19.8 at 5 sigma; COLIBRI/DDRAGO z-band imaging from 4.9739 to 6.2776 hr post-trigger found no new source to z > 20.9 at 5 sigma.
No observations are mentioned in gamma-ray, radio, infrared, ultraviolet, gravitational-wave, or neutrino bands.
Lightcurve and spectrum
- EP-WXT trigger time: 2026-07-31T00:54:24 UTC.
- NOT stacked z-band limit: z ~ 19.8 at a median time of 2.46 hr post-trigger.
- COLIBRI stacked z-band limit: z > 20.9 from observations spanning 4.9739 to 6.2776 hr after the trigger.
Redshift
What’s special vs typical