Reactionp¯p→Λ¯Λ in the meson-exchange picture

A study of the strangeness production process p¯p→Λ¯Λ at threshold and intermediate energies has been performed doing a full coupled-channel (p¯p,Λ¯Λ) calculation. The elastic part of the p¯p and Λ¯Λ interactions has been derived from a one-boson-exchange version of the Bonn NN potential and a corresponding extension to the hyperon-nucleon case whereas the annihilation part is taken into account by introducing suitable optical potentials. The transition interaction between p¯p and Λ¯Λ is based on K- and ${\mathit{K}}^{\mathrm{*}}$-meson exchange. A reasonably good description of empirical cross sections as well as polarization data is achieved. It is demonstrated that the results are quite sensitive even to short-range modifications of the channel interactions. We also compare our model with other approaches and suggest a new experiment which would be able to check the very different predictions of the meson-exchange and constituent quark model, respectively.