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Pentaquark $Θ^+$ in nuclear matter and $Θ^+$ hypernuclei

H. Shen·H. Toki
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Abstract

We study the properties of the $Θ^+$ in nuclear matter and $Θ^+$ hypernuclei within the quark mean-field (QMF) model, which has been successfully used for the description of ordinary nuclei and $Λ$ hypernuclei. With the assumption that the non-strange mesons couple only to the $u$ and $d$ quarks inside baryons, a sizable attractive potential of the $Θ^+$ in nuclear matter is achieved as a consequence of the cancellation between the attractive scalar potential and the repulsive vector potential. We investigate the $Θ^+$ single-particle energies in light, medium, and heavy nuclei. More bound states are obtained in $Θ^+$ hypernuclei in comparison with those in $Λ$ hypernuclei.

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H. Shen, H. Toki. 2005-07-05. Pentaquark $Θ^+$ in nuclear matter and $Θ^+$ hypernuclei. https://doi.org/10.1103/physrevc.71.065208

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