$πB_{8}B_{8}$ and $σB_{8}B_{8}$ couplings from a chiral quark potential model

Abstract

From an SU(2)$\otimes $SU(2) chiral quark potential model incorporating spontaneous chiral symmetry breaking the asymptotic $π$ and $σ$ exchange pieces of the $NN$ potential are generated. From them the $πNN$ and $σNN$ coupling constants can be extracted. The generalization to SU(3)$\otimes $SU(3) allows for a determination of $πB_{8}B_{8}$ and $% σB_{8}B_{8}$ coupling constants according to exact SU(3) hadron symmetry. The implementation of the values of the couplings at $Q^{2}=0$ provided by QCD sum rules and/or phenomenology makes also feasible the extraction of the meson-baryon-baryon form factors. In this manner a quite complete knowledge of the couplings may be attained.

21 pages, 4 figures, 3 tables