A NEW DISCRIMINATOR FOR GAMMA-RAY BURST CLASSIFICATION: THE Epeak-FLUENCE ENERGY RATIO

Using the derived gamma-ray burst (GRB) E-peak and fluences from the complete BATSE 5B Spectral Catalog, we study the ensemble characteristics of the E-peak-fluence relation for GRBs. This relation appears to be a physically meaningful and insightful fundamental discriminator between long and short bursts. We discuss the results of the lower limit test of the E-peak-E-iso relations in the E-peak-fluence plane for Burst And Transient Source Experiment bursts with no observed redshift. Our results confirm the presence of two GRB classes as well as heavily suggesting two different GRB progenitor types.