ENERGY-INDEPENDENT HYPERON-NUCLEON EFFECTIVE INTERACTIONS

Energy-independent hyperon-nucleon (YN) effective interactions are der ived from the Julich JA and JB meson-exchange potentials. A folded-dia gram method is employed, where the effective interaction V-eff is give n as a (Q) over cap-box folded-diagram series. A model space consisted of nucleons in the Op1sOd shells and hyperons in the OsOp shells is e mployed. We first derive the YN G-matrix corresponding to this model s pace, with an accurate treatment of the Pauli exclusion operator for t he G-matrix. Then the (Q) over cap-box is evaluated including diagrams first- and second-order in G. A non-degenerate Lee-Suzuki iteration m ethod is employed to sum up the folded-diagram series. We have applied our derived V-eff to O-18(inverted V), and have found that the effect s of core polarization and folded diagrams are both important for the YN V-eff.