Parametrization of pion-nucleon phase shifts and effects upon pion-nucleus scattering calculations.

Abstract

Pi meson interactions with free nucleons as known from recent experiments have been fit by Arndt {ital et} {ital al}. in the form of phase shifts. In the present work these phase shifts are fit by a simple parametrization, and observables computed from the resulting parametrized phase shifts are compared successfully to important examples of recent measurements. The parameters of this work are readily suited to pion-nucleus optical model codes built upon the impulse approximation. Some examples of the effect of the new pion-nucleon data upon these pion-nucleus calculations are shown, relative to older results based upon far fewer pion-nucleon data. {copyright} {ital 1996 The American Physical Society.}