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Roles of Quarks in Strong and Weak YN Interactions

M. Oka·Y. Tani·T. Inoue·K. Sasaki
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Abstract

The short range parts of the strong and weak hyperon-nucleon interactions are studied with quark substructure of the baryons taken into account. A summary of the quark cluster model calculations of the baryon-baryon interactions is presented. It is pointed out that the spin-flavor symmetry structure determines the qualitative behaviors of the short-range YN interactions. We also show that the spin-orbit YN forces give characteristic behaviors, which are distinct from the meson exchange forces. Weak decays of $Λ$ in hypernuclei are described by the direct quark mechanism. We find that the neutron induced nonmesonic decay is enhanced due to the direct quark transition. Importance of the $ΔI=3/2$ decay amplitudes is emphasized both for the nonmesonic weak decays and the $π^+$ emission in the $Λ$ decay.

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M. Oka, Y. Tani, T. Inoue, K. Sasaki. 1998-11-10. Roles of Quarks in Strong and Weak YN Interactions. https://arxiv.org/abs/nucl-th/9811033

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