General information
GRB 260512A is a likely long-duration GRB detected by Fermi/GBM at 2026-05-12 16:56:43 UT, with prompt emission also reported by NuSTAR (ACS), AstroSat/CZTI, Konus-Wind, and Mars Odyssey, and an IPN triangulation localization.
Wavelength coverage
- Gamma-ray / hard X-ray: Fermi/GBM trigger and localization; NuSTAR CsI shields prompt detection; AstroSat CZTI (20–200 keV) and Veto (100–500 keV) detection; Konus-Wind detection with spectroscopy (20 keV–10 MeV); IPN includes Mars-Odyssey detection.
- Optical: MASTER-OAFA reported only upper limits to ~19.9 mag (clear/C) at ~1.28 days post-trigger.
No observations were mentioned in radio, infrared, ultraviolet, soft X-ray afterglow imaging, TeV, neutrinos, or gravitational waves.
Lightcurve and spectrum
- NuSTAR CsI shields: ~10 s long burst consistent with the Fermi/GBM lightcurve; peak ~2500 cps over ~1000 cps baseline; no evidence above 100 keV in CZT detectors.
- AstroSat CZTI: light curve peak at 16:56:47.5 UTC; T90 = 13(+1,-1) s (20–200 keV). Veto: peak at 16:56:46.4 UTC; T90 = 10(+2,-2) s (100–500 keV).
- Konus-Wind: multipeaked structure with total duration ~23 s; emission up to ~2 MeV; fluence 2.45(-0.24,+0.20)×10^-5 erg/cm^2 and 64-ms peak flux 6.32(-0.82,+0.83)×10^-6 erg/cm^2/s (20 keV–10 MeV). Band-model fits reported with Ep ~202 keV (time-averaged) and Ep ~193 keV (near peak), with alpha/beta values given in the circular.
Redshift
What’s special vs typical