Effects of instantons on P-wave multiquark systems.

Abstract

We study noncentral parts of the flavor-singlet interquark interactions induced by the instanton-light-quark coupling and their effects on the $P$-wave multiquark systems: the negative parity nonstrange baryons and the relative $P$-wave two-nucleon systems. It is found that the noncentral force from the instanton induced interaction reduces that from the one-gluon exchange in the excited $P$-wave nucleons. This cancellation does not occur in the spin-orbit force between nucleons, where the flavor-symmetric $q\ensuremath{-}q$ interaction plays a dominant role.