Quark model for baryon-baryon processes

Abstract

A quark (Q) model recently proposed by the authors for high-energy meson-baryon and photoproduction processes is extended to high-energy baryon-baryon scattering and production of negative-parity baryons. The positive- and negative-parity baryons are assumed to belong, respectively, to the representations (56,1) and (70,3) of the group SU(6)×O(3). Sum rules resembling those of SU(3) and SU(6,6), but differing in details, are obtained for the baryon-baryon processes within the 56 representation. An interesting sum rule which is obtained for negative-parity baryon production involves only nonstrange particles and could be within fairly early reach of experiment. The model is primarily characterized by an impluse approximation for Q-Q scattering and thus disallows processes involving exchanges of more than one unit of charge, hypercharge, and even spatial symmetry, among the initial and final 3Q states representing the baryons. This last condition precludes the high-energy peripheral production of metastable baryon states like the Roper resonance, which we believe to have an internal orbital structure of L^P=1⁺.