Phi meson production cross sections in pion-baryon and baryon-baryon interactions

Abstract

Phi meson production in pion-baryon and baryon-baryon interactions near the production threshold is studied in a boson-exchange model. Parameters in this model are either taken from the Bonn model for the nucleon-nucleon potential or determined from the measured phi meson decay width and the experimental data for the reactions $π^-p\arr ϕn$ and $pp\arr ppϕ$. The isospin-averaged cross sections for the reactions $πN\arr ϕN$, $πΔ\arr ϕN$, $NN\arr NNϕ$, which are needed in transport models to study phi meson production in heavy-ion collisions at subthreshold energies, have been evaluated. For the reactions $NΔ\arr NNϕ$ and $ΔΔ\arr NNϕ$, which become singular when the exchanged pion is on-shell, the Peierls method is used to calculate their cross sections. We find that the cross section for the reaction $πN\arrϕN$ is much larger than the other cross sections.