STRANGENESS MATRIX-ELEMENTS IN THE NUCLEON

We investigate the strangeness "content" of the proton in three nucleonic models: a simple relativistic meson-loop picture, a naive nonrelativistic quark model with mesons, and an extended cloudy bag model. In each case, pseudoscalar mesons are included. Nucleon matrix elements involving strange quarks are generated through the formation of a kaon cloud. We concentrate on the last two models, with the one free parameter chosen to reproduce the electromagnetic nucleon observables. We give theoretical predictions for F2s(0), the strange quark contribution to the weak magnetic form factor, [r2]s, the strangeness radius of the nucleon, and g(A)s, the strangeness axial vector matrix element. We observe a strong dependence of the strange quark matrix elements on the choice of the momentum cutoff or bag size.