LOW-ENERGY PROTON-ANTIPROTON SCATTERING IN THE NONRELATIVISTIC P-3(0)QUARK-MODEL

We are investigating low-energy proton-antiproton-scattering cross sec tions in the framework of a potential model. The nucleon-antinucleon i nteraction is assumed to have two parts. The short-range annihilation part is derived from a non-relativistic quark model where nucleon-anti nucleon transitions involving two- and three-meson final states are ta ken into account. The underlying quark dynamics is ruled by annihilati on diagrams, where quark-antiquark pairs are created or destroyed with vacuum quantum numbers (P-3(0) n LS-coupling). The long- and medium-r anged elastic interaction is taken from a G-parity-transformed one-bos on-exchange model for the nucleon-nucleon interaction. We present mode ls, employing differing one-boson-exchange parts, as defined by the Bo nn and the Paris potentials. We compare the results for the total, ela stic, annihilation, charge-exchange and differential cross sections wi th the experimental data. We encounter an old shortcoming of microscop ic models - albeit in a somewhat improved form: their inability to ful ly understand the total flux into the annihilation channels. We show t hat the annihilation cross section strongly depends on the elastic int eraction.