Einstein Probe detects X-ray transient EP260707a but later classified as a false alarm.

AI Summary

Initial detection by Einstein Probe's WXT led to follow-up observations, but subsequent analysis revealed it to be a false alarm with no real transient detected optically.

Measurements

Notices (1)

Einstein Probe WXT — GRB · Tue, 07 Jul 2026 16:45:24 GMT

GCN Circulars (5)

GCN-45112 — EP260707a · Wed, 08 Jul 2026 04:41:03 GMT
Astronomers using the Nordic Optical Telescope did not detect any new optical transient in the field of an uncatalogued X-ray source detected by EP-FXT, setting a 5-sigma limiting magnitude of r ~ 23.0 (AB). This observation was part of the follow-up to the very likely fake event of EP260707a.

GCN-45111 — EP260707a · Wed, 08 Jul 2026 02:34:57 GMT
The X-ray transient candidate EP260707a, initially detected by the Einstein Probe mission, has been determined to be a false alarm. The source detected by the Follow-up X-ray Telescope is considered a coincidental alignment rather than a real transient.

GCN-45110 — EP260707a · Tue, 07 Jul 2026 21:12:22 GMT
Astronomers Robert Strausbaugh and A. Cucchiara reported observations of the EP260707a field using the LCOGT 1-meter Sinistro instrument, finding no uncatalogued source in the FXT error region. The optical upper limits were determined to be r > 22.1 and i > 21.6, consistent with other reports.

GCN-45109 — EP260707a · Tue, 07 Jul 2026 19:33:31 GMT
An observation of the field of EP260707a, detected by EP, was conducted using the 0.7-m telescope of the Thai Robotic Telescope network (TRT) in New South Wales, Australia. No uncatalogued optical transient was detected within the error circle, with a 5-sigma limiting magnitude of R ~ 21.0 (Vega).

GCN-45107 — EP260707a · Tue, 07 Jul 2026 18:30:09 GMT
Astronomical alert: EP260707a: Einstein Probe detection of an X-ray transient