Einstein Probe detects X-ray transient EP260731a with short duration

AI Summary

An X-ray transient, EP260731a, was detected by Einstein Probe's WXT and later confirmed by FXT, showing a short duration of 35 seconds with an average unabsorbed flux of 1.15 x 10^-12 erg s^-1 cm^-2 in 0.5-10 keV.

Measurements

Notices (1)

Einstein Probe WXT — GRB · Fri, 31 Jul 2026 00:54:24 GMT

GCN Circulars (4)

GCN-45301 — EP260731a · Fri, 07 Aug 2026 03:41:59 GMT
The X-ray transient EP260731a, detected by the Einstein Probe mission, was analyzed to have started on 2026-07-31 at 00:53:50 UTC and lasted for 35 seconds. The Follow-up X-ray Telescope (FXT) on board the Einstein Probe observed an uncatalogued X-ray source consistent with the WXT position, with a derived average unabsorbed 0.5-10 keV flux of 1.15 x 10^-12 erg s^-1 cm^-2.

GCN-45264 — EP260731a · Fri, 31 Jul 2026 07:24:07 GMT
The COLIBRÍ telescope observed the field of EP260731a and did not detect any new source at the FXT source position, setting a 5-sigma upper limit of z > 20.9. This non-detection is consistent with previous reports and further observations are ongoing.

GCN-45263 — EP260731a · Fri, 31 Jul 2026 04:39:27 GMT
The Nordic Optical Telescope (NOT) observed the field of EP260731a, detected by EP, and found no optical transient within the error circle down to a 5-sigma limiting magnitude of z ~ 19.8, 2.46 hours post-trigger. The observation was conducted under challenging conditions with the target 16 degrees from a 98% illuminated moon.

GCN-45261 — EP260731a · Fri, 31 Jul 2026 02:15:53 GMT
The Einstein Probe (EP) mission has detected an X-ray transient, designated EP260731a, using its Wide-field X-ray Telescope (WXT). A follow-up observation with the Follow-up X-ray Telescope (FXT) confirmed an uncatalogued X-ray source within the WXT error circle, indicating a significant astronomical event.