Scalar kappa meson in K* photoproduction

Abstract

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

Comments: 9 pages, 4 figures, REVTeX