The Proton Spin Puzzle and $Λ$ Polarization in Deep--Inelastic Scattering

Abstract

We point out that measurements of longitudinal $Λ$ polarization in the target fragmentation region of deep--inelastic $ν\,N$ and $μ\,N$ or $e \, N$ scattering may test dynamical mechanisms invoked to explain the proton spin puzzle. A previously-proposed model for polarized $\bar s s$ pairs in the proton wave function reproduces successfully the negative $Λ$ polarization found in the WA59 $\bar ν\, N$ experiment, and makes predictions that could be tested in future $μ\, N$ and $e \, N$ experiments.