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Some aspects of $Θ^+$ parity determination in the reaction $γN\to Θ^+ \bar{K}\to N K \bar{K}$

A. I. Titov·H. Ejiri·H. Haberzettl·K. Nakayama
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Abstract

We analyze the problem of how to determine the parity of the $Θ^+$ pentaquark in the reaction $γN\to KΘ\to NK\bar{K}$, where $N=n,p$. Our model calculations indicate that the contribution of the non-resonant background of the reaction $γN\to NK\bar{K}$ cannot be neglected, and that suggestions to determine the parity based solely on the initial-stage process $γN\to KΘ$ cannot be implemented cleanly. We discuss the various mechanisms that contribute to the background, and we identify some spin observables which are sensitive.

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A. I. Titov, H. Ejiri, H. Haberzettl, K. Nakayama. 2004-10-26. Some aspects of $Θ^+$ parity determination in the reaction $γN\to Θ^+ \bar{K}\to N K \bar{K}$. https://doi.org/10.1103/physrevc.71.035203

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