A phenomenological analysis of antiproton interactions at low energies

We present an optical potential analysis of p̄p interactions at low energies. The optical potential is purely phenomenological, and has been parametrized using data recently obtained by the Obelix Collaboration at momenta below 180 MeV/c. It reasonably fits annihilation and elastic data below 600 MeV/c, and allows an evaluation of the elastic cross section and ρ-parameter down to zero kinetic energy. The used values of the parameters agree with the values suggested by other authors from an analysis of elastic scattering. Moreover we show that the mechanism that suppresses p̄–nucleus annihilation cross sections at low energies is present in p̄p interactions too.