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The Pentaquark $Θ^+$ in $nK^+$ and $pK^0_S$, and its $Σ^+_5$ partner

Qiang Zhao·Frank E. Close
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Abstract

A systematic lowering in mass of strangeness ambiguous $pK^0_S$ peaks relative to the $nK^+$ is noted. We discuss how measurement of $γp\to Θ^+ K^0_S\to p K^0_S K^0_S \to pπ^+π^-π^+π^-$ in association with $γp\to Θ^+ K^0_S\to n K^+ K^0_S$ can help to clarify the nature of the narrow baryon state claimed in $p K^0_S$ invariant mass distributions. This can both establish the $Θ^+$ in a single experiment and also reveal, or place severe limits on, the existence of an associated $Σ_5$ pentaquark.

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Qiang Zhao, Frank E. Close. 2005-02-02. The Pentaquark $Θ^+$ in $nK^+$ and $pK^0_S$, and its $Σ^+_5$ partner. https://doi.org/10.1088/0954-3899%2F31%2F1%2Fl01

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