Spin Observables in Consistent Relativistic Models of (e, e'p) and (gamma, p) Reactions

Abstract

Single nucleon knockout reactions must be described in a consistent framework in order to extract information about nuclear structure and reaction mechanisms. Consistent relativistic models for the direct knockout contribution to the (e, e'p) and (gamma, p) reactions have been developed and used previously to examine existing momentum distribution and cross section data for the two reactions^{1}. We present results of calculations of spin observables obtained from these models of (e, e'p) and (gamma, p) reactions. For the (e, e'p) reaction we consider the importance of the choice of kinematics and show that perpendicular kinematics result in distributions with relatively large cross sections and comparatively large polarizations. In the (gamma, p) reactions the photon asymmetry and proton polarization are not very sensitive to changes in model ingredients when the incident photon energy is less than 100 MeV. For higher energies these observables show increasing sensitivity to modifications of both the bound and continuum wave functions.