Scalar kappa meson in K* photoproduction

Abstract

We propose that the scalar $κ(800)$ meson may play an important role in $K^*$ photoproduction. In the reactions of $γp \to K^{*+} Λ$ and $γp \to K^{*0} Σ^+$, we consider the production mechanisms including $t$-channel $K^*$, $K$, $κ$ exchanges, s-channel $N$, $Δ$ diagrams, and $u$-channel $Λ$, $Σ$, $Σ^*$ diagrams within the tree level approximation, and find that the $κ$-meson exchange may contribute significantly to $K^*Σ$ photoproduction, while it is rather supplementary in $K^*Λ$ photoproduction. We demonstrate how the observables of $K^*$ photoproduction can be used to constrain the $κ$ meson properties. In particular, the parity asymmetry can separate the $κ$ meson contribution in $K^*$ photoproduction.