Photoproduction of K +Λ, and K +Σ0 on the proton

Abstract

I analyze a possibility of building an isobar model of the kaon–hyperon pair photoproduction in the γp → K +Λ, , and γp → K +Σ processes, where the Born terms play a comparatively small role in the full amplitude. The total width of hadron resonances can be written in the form of a sum of partial contributions into the K +Λ, , and K +Σ channels, and the effective inelastic channel with zero strangeness. The introduction of the effective inelastic channel makes it possible to partially restore the broken unitarity of the total amplitude of photoproduction. The latter includes the gauge-invariant Born and resonant s-, t-, and u-channel contributions calculated in the tree-level approximation. The obtained sets of hadron decay widths of intermediate resonances and coupling constants calculated using these decay widths allow one to equally well reproduce the total and some differential cross sections of the K +Λ, , and K +Σ photoproduction.