Spin effects and N annihilation effects in elastic antiproton-nucleus scattering

The differential cross section, the polarisation and the spin-rotation parameter in elastic scattering of 180 MeV antiprotons by ¹²C and ¹⁶O are calculated by means of Glauber's multiple scattering theory and Pauli-correlated wavefunction. The effects of N(mean)N annihilation are studied by using a phenomenological N(mean)N annihilation potential within this framework. The results indicate that spin effects are negligible at small angles but that at large angles spin effects improve the elastic angular distribution, and that the N(mean)N annihilation part of the amplitudes contributes significantly to the observables.