Electroproduction of kaons from the proton in a Regge-plus-resonance approach

Abstract

We present a Regge-plus-resonance (RPR) description of the p(e,e'K^+)Y processes (Y=Λ,Σ^0) in the resonance region. The background contributions to the RPR amplitude are constrained by the high-energy p(γ, K^+)Y data. As a result, the number of free model parameters in the resonance region is considerably reduced compared to typical effective-Lagrangian approaches. We compare a selection of RPR model variants, originally constructed to describe $KY$ photoproduction, with the world electroproduction database. The electromagnetic form factors of the intermediate N^*s and $Δ^*s are computed in the Bonn constituent-quark model. With this input, we find a reasonable description of the p(e,e'K^+)Y data without adding or readjusting any parameters. It is demonstrated that the electroproduction response functions are extremely useful for fine-tuning both the background and resonant contributions to the reaction dynamics.

14 pages, 7 figures; added discussion on double counting in the RPR model; accepted for publication in Phys. Lett. B