Unified description of NN and YN interactions in a quark model with effective meson-exchange potentials.

A simultaneous description of the {ital NN} and {ital YN} interactions is attempted in the resonating-group formulation of the spin-flavor SU{sub 6} quark model, in which the full Fermi-Breit interaction with explicit quark-mass dependence acts between quarks, and all the mesons of scalar and pseudo-scalar nonets couple directly to quarks. An overall agreement with the existing data is obtained with few adjustable parameters. In the {Lambda}{ital p} elastic total cross sections, the cusp structure at the {Sigma}{ital N} threshold is strongly enhanced by the antisymmetric {ital LS}{sup ({minus})} force generated from the Fermi-Breit interaction. {copyright} {ital 1996 The American Physical Society.}