Photoproduction of K Mesons in Hydrogen near Threshold

The total cross sections near threshold of the three processes: γ+p→Λ⁰+K⁺, Σ⁰+K⁺, Σ⁺+K⁰, have been calculated as a function of the incident photon energy in the laboratory system under the assumptions that the hyperons have spin ⁺ with positive anomalous magnetic moments and that the K meson has spin 0±{} and is coupled to the baryon field by direct Yukawa interaction. A pseudoscalar K meson gives a steep increase of the cross section for neutral production and at the same time gives a large K⁰K⁺ production ratio compared to that for a scalar K meson.