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Spin observables and the determination of the parity of $Θ^+$ in photoproduction reactions

K. Nakayama·W. G. Love
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Abstract

Spin observables in the photoproduction of the $Θ^+$ are explored for the purpose of determining the parity of the $Θ^+$. Based on reflection symmetry in the scattering plane, we show that certain spin observables in the photoproduction of the $Θ^+$ can be related directly to its parity. We also show that measurements of both the target nucleon asymmetry and the $% Θ^+$ polarization may be useful in determining the parity of $Θ^+$ in a model-independent way. Furthermore, we show that no combination of spin observables involving only the polarization of the photon and/or nucleon in the initial state can determine the parity of $Θ^+$ unambiguously.

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K. Nakayama, W. G. Love. 2004-07-28. Spin observables and the determination of the parity of $Θ^+$ in photoproduction reactions. https://doi.org/10.1103/physrevc.70.012201

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