General information
GRB 260616B was detected by Fermi GBM at 07:05:16.39 UT on 2026-06-16, with consistent GBM and BALROG localizations near RA 256–257.5 deg and Dec about -32 deg. The reported statistical localization uncertainty is 1.5–1.7 deg (1 sigma), with additional systematic uncertainty noted in both analyses.
Wavelength coverage
- Gamma-ray: Fermi GBM detected the burst and reports prompt-emission timing, localization, fluence, peak flux, and a Band-function spectral fit.
No observations are mentioned in radio, millimeter/submillimeter, infrared, optical, ultraviolet, X-ray, or non-electromagnetic channels.
Lightcurve and spectrum
- The GBM light curve consists of two main pulses.
- The duration is T90 about 13.8 s in the 50–300 keV band.
- The time-averaged spectrum from T0+0.002 to T0+14.464 s is best fit by a Band function.
- The fitted spectral parameters are Epeak = 240 +/- 10 keV, alpha = -0.63 +/- 0.04, and beta = -2.09 +/- 0.06.
- The fluence in 10–1000 keV is (2.03 +/- 0.03)E-05 erg/cm^2.
- The 1 s peak photon flux starting at T0+10 s in 10–1000 keV is 21.3 +/- 0.4 ph/s/cm^2.
Redshift
What’s special vs typical
- The event is better characterized than a minimal trigger because prompt gamma-ray temporal and spectral properties are already reported, and two Fermi-based localization products are available.
- Based on the provided text alone, it still looks typical of a routine GBM GRB notice rather than an unusually special burst with counterpart, host, redshift, or multi-messenger association.