SU(3) systematization of baryons

Abstract

We review the spectrum of all baryons with the mass less than approximately 2000-2200 MeV using methods based on the approximate flavor SU(3) symmetry of the strong interaction. The application of the Gell-Mann--Okubo mass formulas and SU(3)-symmetric predictions for two-body hadronic decays allows us to successfully catalogue almost all known baryons in twenty-one SU(3) multiplets. In order to have complete multiplets, we predict the existence of several strange particles, most notably the \Lambda hyperon with J^P=3/2^-, the mass around 1850 MeV, the total width approximately 130 MeV, significant branching into the \Sigma \pi and \Sigma(1385) \pi states and a very small coupling to the N \bar{K} state. Assuming that the antidecuplet exists, we show how a simple scenario, in which the antidecuplet mixes with an octet, allows to understand the pattern of the antidecuplet decays and make predictions for the unmeasured decays.