Polarization inπ−−pScattering between 500 and 940 Mev

Abstract

A graphite-plate spark chamber has been used to analyze the polarization of protons recoiling from ${\pi }^{-}-p$ scattering. The observations were made at 90° (c.m. system) pion scattering angle for seven incident pion energies between 500 and 940 Mev, at 120° or 135° for five energies in this interval, and also at 75° for 500 Mev only. The results are compared with predictions of several models used to explain the maxima in the ${\pi }^{-}-p$ scattering cross section. Qualitative arguments show that the energy intervals between these maxima are not completely dominated by neighboring single-state resonances. Phase shifts found to be large in scattering also seem to be large in polarization.