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High Resolution Search for Exotic Pentaquark $Θ^{++}$, and $Θ^+$ at Jefferson Lab

Haiyan Gao·Wang Xu
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Abstract

Recent evidence for the existence of pentaquark $Θ^+$ particle from several experiments at several different laboratories around the world has caused great excitement and raised many unanswered questions. We discuss a new proposal on a high resolution experiment searching for pentaquark states in Hall C at Jefferson Lab using an untagged bremsstrahlung photon beam employing both the hydrogen and the deuterium targets by studying the following processes: $γp \to Θ^{++} K^-$, and $γn \to Θ^+ K^-$. This new experiment will significantly improve our current knowledge of the mass, the width of the $Θ^+$ particle if it is confirmed and provide unambiguous evidence for the existence or non-existence of the $Θ^{++}$ particle from the γp \to Θ^{++} K^-$ process.

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Haiyan Gao, Wang Xu. 2004-11-08. High Resolution Search for Exotic Pentaquark $Θ^{++}$, and $Θ^+$ at Jefferson Lab. https://arxiv.org/abs/nucl-ex/0411013

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