General information
EP-WXT transient EP260105b (GRB 260105C) had full Fermi-GBM coverage and a sub-threshold GBM targeted-search signal around the EP trigger time (T0=2026-01-05T18:47:36 UTC). The most significant GBM signal occurs at T0-32 s on a 16 s timescale and is spatially consistent with the EP localization (96.3% association probability).
Wavelength coverage
- X-ray: Detected by Einstein Probe WXT (EP260105b).
- Gamma-ray: Sub-threshold detection in Fermi-GBM targeted search (no onboard trigger).
No observations were mentioned for radio, optical/IR, UV, or TeV.
Lightcurve and spectrum
- Temporal: Most significant GBM signal at T0-32 s on a 16 s timescale.
- Spectrum: Best-fit “normal” Band template with Epeak = 230 keV, alpha = -1.0, beta = -2.3.
- Significance: False alarm rate = 6.5e-05 Hz.
Redshift
What’s special vs typical
- The prompt gamma-ray signal is sub-threshold (no onboard GBM trigger) yet shows a high spatial association probability (96.3%) with the EP-WXT transient localization.