Fermi GBM GRBs' multivariate statistics

Studying their gamma-ray spectra may reveal some physical information on -ray bursts (GRBs). The Fermi satellite has observed more than 2,000GRBs. The FERMIGBRST catalog contains the GRB parameters (peak energy, spectral indices, intensity) estimated for both the total emission (fluence) and the emission during the interval of the peak flux. We found a relationship with linear discriminant analysis between the spectral categories and the model-independent physical data. We compared the Swift and Fermi spectral types, and found a connection between the Fermi fluence spectra and the Swift spectra, but the result of the peak flux spectra can be disputable. We found that those GRBs that were observed by both Swift and Fermi can similarly discriminate as the complete Fermi sample. We conclude that the common observation probably did not find any trace of selection effects in the spectral behavior of GRBs.