image hyperon and hypernuclear production in the image reaction on nucleon and nuclei in a field theoretical model

We investigate the production of a cascade hyperon (Ξ) and bound Ξ hypernuclei in the image reaction on proton and nuclear targets, respectively, within a covariant effective Lagrangian model. The image production vertex is described by excitation, propagation and decay of Λ and Σ resonance states in the initial collision of a image meson with a free or bound proton in the incident channel. The parameters of the resonance vertices are taken from previous studies and SU(3) symmetry considerations. The model is able to provide a good description of the available data on total and differential cross sections for the image reaction. The same mechanism was used to describe the hypernuclear production reactions image and image, where Ξ bound state spinors calculated within a phenomenological model have been employed. Both the elementary and hypernuclear production cross sections are dominated by the contributions from the image intermediate resonant state. The beam momentum dependence of the 0° differential cross sections for the formation of the Ξ hypernuclei is found to be remarkably different from what has been observed previously in the impulse approximation model calculations.