Study the exotic ${\Theta }^{+}$ in polarized photoproduction reactions

Abstract

We present an analysis of a Beam-Target double polarization asymmetry in $\gamma n\to {\Theta }^{+}{K}^{-}$. We show that this quantity can serve as a filter for the determination of the ${\Theta }^{+}$'s spin-parity assignment near threshold. It is highly selective between $1/2^{+}$ and $1/2^{-}$ configurations due to dynamical reasons.

Comments: Plenary talk at NSTAR2004, Proceedings of the Workshop on the Physics of Excited Nucleons, p.63 (2004), Grenoble, France, Mar. 2004