General information
GRB 260604A is a likely long GRB detected by Fermi/GBM at 2026-06-04 02:24:27 UT and independently reported by Glowbug, SVOM/GRM, 239Alferov, and Konus-Wind. The Fermi/GBM localization is RA = 60.4 deg, Dec = -12.8 deg with a 9.3 deg statistical uncertainty.
Wavelength coverage
- Gamma-ray: Fermi/GBM detected and localized the event; Glowbug measured about 9.8 sigma significance and a 4.1 s duration; SVOM/GRM measured T90 = 4.0 +4.2/-2.2 s and a prompt spectrum/fluence; 239Alferov detected a roughly 5 s pulse with emission up to about 500 keV; Konus-Wind detected the burst in waiting mode.
- Optical/UV: SVOM/ECLAIRs did not observe the burst because it was outside the ECLAIRs field of view.
No observations are mentioned in X-ray, radio, infrared, neutrino, or gravitational-wave bands.
Lightcurve and spectrum
- Glowbug: onset at 2026-06-04 02:24:24.648, duration 4.1 s, total significance about 9.8 sigma, and a single-peak light curve; detector deadtime affected data from about T0-5 s to +1 s.
- SVOM/GRM: multiple pulses with T90 = 4.0 +4.2/-2.2 s in 15-5000 keV.
- SVOM/GRM: time-averaged spectrum from T0+0 to T0+4 s fit by a power law with index -1.69 +0.12/-0.11.
- SVOM/GRM: fluence = (1.01 +0.17/-0.16)E-06 erg/cm^2 in 10-1000 keV.
- 239Alferov: single pulse with duration about 5 s and emission seen up to about 500 keV.
Redshift
What’s special vs typical