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arXiv · hep-ph/0308176

Pentaquark Theta+, constituent quark structures, and prediction of charmed Theta(c)^0 and bottomed Theta(b)^+

Kingman Cheung
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Abstract

The newly observed $Θ^+$ resonance is believed to be a pentaquark with the constituent quarks $uudd\bar s$. There are a few options for the constituent quark structure. Some advocate diquark-diquark-antiquark $(ud)$-$(ud)$-$\bar s$ while others favor diquark-triquark $(ud)$-$(ud\bar s)$. We use the color-spin hyperfine interaction to examine the energy levels of these structures, and we find that the diquark-diquark-antiquark structure is slight favored. We proceed to write down the flavor triplet and antisextet of the charmed or bottomed exotic baryons with internal $qqqq\bar Q$ quarks. We also estimate the mass of $Θ_c^0$ and $Θ_b^+$.

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Kingman Cheung. 2004-04-05. Pentaquark Theta+, constituent quark structures, and prediction of charmed Theta(c)^0 and bottomed Theta(b)^+. https://doi.org/10.1103/physrevd.69.094029

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