EP-WXT01709258519 likely linked to Mrk 421, no optical transient detected.
AI Summary
The Einstein Probe WXT triggered on February 21, 2026, at coordinates corresponding to the known gamma-ray blazar Mrk 421. No optical transient was found in follow-up observations conducted by the Xinglong Observatory.
Measurements
| Event ID | 01709258519 |
|---|---|
| Source | Einstein Probe WXT |
| Alert type | GRB |
| Significance | low |
| Trigger time (UTC) | Sat, 21 Feb 2026 08:28:55 GMT |
| Right ascension (J2000) | 166.254° |
| Declination (J2000) | 38.209° |
| Position error radius | 0.05117579° |
| Image SNR | 7 |
| GCN notices | 1 |
| GCN circulars | 3 |
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.
AI summary generated Sun, 26 Jul 2026 12:17:37 GMT.