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arXiv · hep-ph/0402008

A Mass Inequality for the $Ξ^*$ and $Θ^+$ Pentaquarks

Marek Karliner·Harry. J. Lipkin
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Abstract

We derive an upper bound on the mass difference between the $Ξ^*$ and $Θ^+$ pentaquarks which are the manifestly exotic members of the $SU(3)_f$ antidecuplet. The derivation is based on simple assumptions about $SU(3)_f$ symmetry breaking and uses the standard quantum mechanical variational method. The resulting rather robust bound is more than 20 MeV below the experimentally reported $Ξ^*-Θ^+$ mass difference, emphasizing the need for confirmation of the experimental mass values and placing strong constraints on quark models of the pentaquark structure.

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Marek Karliner, Harry. J. Lipkin. 2004-04-22. A Mass Inequality for the $Ξ^*$ and $Θ^+$ Pentaquarks. https://doi.org/10.1016/j.physletb.2004.05.052

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