Detection of GeV Emission from an Ultralong Gamma-Ray Burst with the Fermi Large Area Telescope
Detection of GeV Emission from an Ultralong Gamma-Ray Burst with the Fermi Large Area Telescope
Abstract GRB 220627A, detected by Fermi Gamma-ray Burst Monitor (GBM), shows two episodes of gamma-ray emission, which are separated by a ∼700 s long quiescent phase. Due to similar temporal shapes and spectra in the two episodes, GRB 220627A is speculated to be a gravitationally lensed gamma-ray burst (GRB). We …