Kaon properties and cross sections in the nuclear medium

Results for the π+N→Λ, Σ+K reactions in nuclear matter of Tsushima K et al (2000 Phys. Rev. C 62 064904) are presented. To evaluate the in-medium modification of the reaction amplitude as a function of the baryonic density we introduce relativistic, mean-field potentials for the initial, final and intermediate mesonic and baryonic states in the resonance model. These vector and scalar potentials were calculated using the quark-meson coupling model. Contrary to earlier work which had not allowed for the change of the cross section in the medium, we find that the data for kaon production at SIS energies are consistent with a repulsive K+-nucleus potential. (author)