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The theory of pentaquarks

Harry J. Lipkin
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Abstract

Is there a theory or good experimental evidence? Bj's question: Pentaquark is created by $e^+e^-$. $2q + q \to$ Baryon $; ~ ~ ~ 2q + \bar q \to $ Triquark$ ; ~ ~ ~ 2q + $Triquark $ \to $Pentaquark Does it live long onough to be observable? Basic physics of constituent quarks and flavor antisymmetry. Report of $Θ^+$ violating flavor antisymmetry indicates need for two-cluster model.. Ball in Experimental Court - Some experiments see $Θ^+$; others don't. Possible production mechanisms present in some experiments, absent in others; e.g. via $N^*(2.3 \rm{GeV}) \to Θ^+ + \bar K$?

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Harry J. Lipkin. 2004-09-29. The theory of pentaquarks. https://arxiv.org/abs/hep-ph/0409349

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