GRB 01709258519 detected by Einstein Probe WXT likely originates from Mrk 421; no optical transient found.
Event ID: 01709258519
Significance: medium
Notices: 1
Circulars: 3
Generated: Fri, 13 Mar 2026 14:14:16 GMT
AI Summary
The Einstein Probe WXT detected a GRB event with a net count rate of 0.03 counts/s in the 0.5-4 keV range. Follow-up optical observations by the Xinglong Observatory did not reveal any new transient within the error circle.
Notices (1)
Einstein Probe WXT — GRB · Sat, 21 Feb 2026 08:28:55 GMT
GCN Circulars (3)
GCN-44232 — EP-WXT01709259586
· Tue, 07 Apr 2026 15:12:09 GMT
Astronomical alert: EP-WXT01709259586: Xinglong optical upper limit
GCN-43799 — EP-WXT01709258519
· Sat, 21 Feb 2026 21:25:15 GMT
The Xinglong Observatory at NAOC reported no detection of a new optical transient in the field of EP-WXT01709258519 using the 2.16-m telescope. The team obtained three 300s clear-band frames with a limiting magnitude of 21.01 mag, which is 11 hours after the EP trigger.
GCN-43790 — The EP-WXT trigger 01709258519 is likely caused by Mrk 421
· Sat, 21 Feb 2026 10:01:16 GMT
The EP-WXT trigger 01709258519, detected on February 21, 2026, is likely linked to the known active galaxy Mrk 421. This event was observed by the Einstein Probe (EP), a space X-ray observatory launched in January 2024.