Polarization transfer and spin correlation experiments in nuclear physics

Abstract

This review is concerned with nuclear reactions and nuclear elastic scattering in which the spin polarization of more than one of the reactants is measured. If both of the particles whose polarization is known are in the initial channel, or both in the final channel, we refer to a `spin correlation' experiment; if one polarized particle is in the initial and one is in the final channel, we refer to a `polarization transfer' experiment. We consider mainly particles with spin ½ and with spin 1; to a minor extent higher spins are included. The state of the art with respect to the production of polarized beams and targets and with respect to polarization analysing devices is briefly reviewed. A considerable amount of space is devoted to the definitions of cartesian polarization transfer and spin correlation coefficients which are suitable for the description of reactions involving spin ½ and spin 1 particles. These parameters are generalizations of the triple scattering and spin correlation parameters introduced by Wolfenstein for a description of nucleon-nucleon scattering. Finally, the experiments of these types so far performed are reviewed. Reactions involving photons are excluded, and the nucleon-nucleon problem is only briefly mentioned.