Spin observables in low energy nucleon-antinucleon scattering

We discuss the model dependence of the spin parameters for low and medium energy antinucleon-nucleon (N̄N) scattering. An N̄N potential model is used, consisting of a t-channel meson exchange part, supplemented by a complex annihilation potential, adjusted to reproduce the observed energy dependence of total elastic, inelastic, and charge exchange cross sections. A number of striking spin effects are predicted, particularly in the charge exchange channel. We explore the sensitivity of the effects to changes in the real and imaginary parts of the N̄N potential; in particular, we assess the possibility of extracting the strength of the coherent N̄N tensor potential due to π, ρ, and ω exchange from future data. Some implications of our results for future experiments are mentioned.NUCLEAR REACTIONS Nucleon-antinucleon scattering, spin-dependent observables.