Decays of Baryon Resonances in an O(3.1) Model

Abstract

AbstractThe notion of dynamical groups [1] has been introduced into hadron physics in order to relate amplitudes of particles of many different spins. In particular the O(3.1)‐model of BARUT and KLEINERT [5a, 6] gives the pseudoscalar form factors of all the strange and non‐strange baryons in terms of a few adjustable coupling constants and claims that they furnish a good approximation in the region of not too large physical momentum transfers. Here we report on an extensive comparison of this O(3.1)‐model with experimental information. For one such comparison we take the known partial decay widths [7] of baryon resonances into members of the nucleon and pseudoscalar meson octet. The fit which we obtain is quite good and the SU(3) symmetry breaking is described in much better agreement with experiment than in an approach which, instead of O(3.1)‐form factors, takes only the correct threshold behavior into account. Further we look at baryon decays with two final mesons and calculate theoretical Dalitz‐plots. Very good agreement with some recent results on Δ(1920) → Δ Kπ is achieved. Finally we give some closed functional form for the form factors which approximate the complicated O(3.1) form factors well in the region relevant for phenomenological calculations.