NONPERTURBATIVE INTERACTIONS AMONG PARTONS

We propose a model of interactions among <<wee>> quarks and antiquarks . Our fundamental assumption is that such partons may give rise -throu gh nonperturbative interactions-to pseudoscalar q-qBAR bosons and to s calar diquarks; in particular we suppose that sea is organized in pseu doscalar q-qBAR bosons. Some of the interactions that a valence quark has, either with another valence quark or with sea, modify the predict ions of the naive quark-parton model about the spin and spin-averaged quark densities. In order to take into account these modifications, we have suitably parametrized the probability densities relative to the interactions in question; moreover we have fixed all the parameters in volved, in such a way that our model matches some data of nucleon stru cture functions and of low-energy hadron physics. Our model has some p redictive power with respect to other data of deep inelastic scatterin g, in particular with respect to the recent EMC and NMC data; furtherm ore some predictions do not depend on the specific parametrizations ch osen for the probability densities, but only on the kinds of interacti ons assumed. The predictions are in good agreement with available data .