Einstein Probe detects X-ray transient EP260314a with no confirmed optical counterpart.

AI Summary

EP260314a was detected as an X-ray transient by Einstein Probe's WXT and FXT, with follow-up observations failing to identify a persistent optical counterpart.

Notices (1)

Einstein Probe WXT — GRB · Sat, 14 Mar 2026 22:51:36 GMT

GCN Circulars (9)

GCN-44025 — EP260314a · Mon, 16 Mar 2026 13:00:42 GMT
The Xinglong Observatory at NAOC reported no detection of an optical transient in the error circle of EP260314a, which was previously detected by EP-WXT, down to a limiting magnitude of g = 21.5. No apparent brightening was observed for catalogued sources within the error circle.

GCN-44024 — EP260314a · Mon, 16 Mar 2026 10:31:28 GMT
A team of astronomers led by Amar Aryan at National Central University reported an optical upper limit for the transient EP260314a using the 1m LOT at the Lulin observatory as part of the Kinder collaboration. No optical counterpart was detected in the stacked or difference image, and an upper limit of >22.8 AB mag was obtained. This result is consistent with previous non-detections.

GCN-44019 — EP260314a · Sun, 15 Mar 2026 12:33:39 GMT
A team of international astronomers using the COLIBRÍ telescope at the Observatorio Astronómico Nacional in Mexico conducted follow-up observations of the gamma-ray burst EP260314a. They did not detect the reported optical counterpart candidate down to the limits of i > 24.08 and z > 23.17. The non-detection may suggest that the candidate is fading, strengthening the hypothesis that it is the true counterpart.

GCN-44016 — EP260314a · Sun, 15 Mar 2026 09:29:55 GMT
The Einstein Probe (EP) mission detected a new X-ray transient, EP260314a, using its Wide-field X-ray Telescope (WXT) and Follow-up X-ray Telescope (FXT). The transient was observed for approximately 16 seconds with WXT and 2.9ks with FXT. The X-ray spectra were fitted with absorbed power laws, and the derived fluxes and hydrogen column densities are reported. The FXT observation revealed an uncatalogued source consistent with the WXT position. The optical follow-up observations are ongoing to explore the nature of this transient.

GCN-44015 — EP260314a · Sun, 15 Mar 2026 09:27:12 GMT
The BOOTES-6/DPR team at Boyden Observatory reported no detection of a new optical source at the position of EP260314a, a gamma-ray transient detected by Einstein Probe, using the 0.6m robotic telescope. They obtained upper limits of magnitudes 18.5, 20.9, and 21.7 for exposures of 60s, 300s, and 600s respectively, which align with previous reports.

GCN-44014 — EP260314a · Sun, 15 Mar 2026 09:18:43 GMT
A global observation campaign led by the MASTER-Net collaboration using the MASTER-OAFA robotic telescope in Argentina reported upper limits on the brightness of EP260314a, an astronomical transient, reaching down to 20.1 and 20.4 mag in clear filter observations. The observations were initiated 18771 seconds after the notice time and 31448 seconds after the trigger time, with the sun altitude being -37.3 degrees.

GCN-44013 — EP260314a · Sun, 15 Mar 2026 03:58:26 GMT
The Space Variable Objects Monitor (SVOM) team reported the detection of a new optical source, EP260314a, in the error box of the Einstein Probe observation. The source was detected in the VT_R channel with a magnitude of 22.70+/-0.26 mag, while no significant detection was made in the VT_B channel. The team could not confirm the fading of the candidate due to limited data. The source is located at R.A. (J2000) = +14:07:22.14, Dec. (J2000) = -23:27:27.82 with an uncertainty of 0.5 arcsec.

GCN-44010 — EP260314a · Sun, 15 Mar 2026 02:16:51 GMT
The Einstein Probe mission, launched in 2024, has detected an X-ray transient designated EP260314a using its Wide-field X-ray Telescope (WXT). The transient's position was determined to be R.A. = 211.845 deg, DEC = -23.445 deg (J2000) with an uncertainty of 3 arcmin. A follow-up observation with the Follow-up X-ray Telescope (FXT) identified an uncatalogued X-ray source at R.A. = 211.8437 deg, DEC = -23.4601 deg (J2000) with a smaller uncertainty of 20 arcsec. Further information will be provided once telemetry data is received.

GCN-44009 — The EP-WXT trigger 01709258851 · Sun, 15 Mar 2026 01:07:35 GMT
A team of astronomers using the Las Cumbres 1m telescope at Sutherland Observatory did not detect any uncataloged source within the error circle of EP-WXT trigger 01759258851, reaching a limiting magnitude of 21.5 mag 50 minutes after the trigger. No further information on the nature or significance of the trigger was provided in the alert.