Julich hyperon-nucleon model revisited

A one-boson-exchange model for the hyperon-nucleon (Lambda N,Sigma N) interaction is presented. The model incorporates the standard one boson exchanges of the lowest pseudoscalar and vector meson multiplets with coupling constants fixed by SU(6) flavor symmetry relations. As the main new feature of the model, the contributions in the scalar-isoscalar (sigma) and vector-isovector (rho) exchange channels are now constrained by a microscopic model of correlated pi pi and K (K) over bar exchange. Additional short-ranged ingredients of the model in the scalar-isovector (a(0)) and scalar-isospin-1/2 (kappa) channels are likewise viewed as arising from meson-meson correlations but are treated phenomenologically. With this model a satisfactory reproduction of the available hyperon-nucleon data can be achieved.