Distinguishing short and long Fermi gamma-ray bursts

Two classes of gamma-ray bursts (GRBs), short and long, have been determined without any doubts, and are usually ascribed to different progenitors, yet these classes overlap for a variety of descriptive parameters. A subsample of 46 long and 22 short Fermi GRBs with estimated Hurst Exponents (HEs), complemented by minimum variability time-scales (MVTS) and durations (T-90) is used to perform a supervised machine learning and Monte Carlo simulation using a support vector machine algorithm. It is found that while T-90 itself performs very well in distinguishing short and long GRBs, the overall success ratio is higher when the training set is complemented by MVTS and HE. These results may allow us to introduce a new (non-linear) parameter that might provide less ambiguous classification of GRBs.