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arXiv · 0807.2973

Towards an understanding of heavy baryon spectroscopy

Abstract

The recent observation at CDF and D0 of $Σ_b$, $Σ^*_b$ and $Ξ_b$ baryons opens the door to the advent of new states in the bottom baryon sector. The states measured provide sufficient constraints to fix the parameters of phenomenological models. One may therefore consistently predict the full bottom baryon spectra. For this purpose we have solved exactly the three-quark problem by means of the Faddeev method in momentum space. We consider our guidance may help experimentalists in the search for new bottom baryons and their findings will help in constraining further the phenomenological models. We identify particular states whose masses may allow to discriminate between the dynamics for the light-quark pairs predicted by different phenomenological models. Within the same framework we also present results for charmed, doubly charmed, and doubly bottom baryons. Our results provide a restricted possible assignment of quantum numbers to recently reported charmed baryon states. Some of them are perfectly described by $D-$wave excitations with $J^P=5/2^+$, as the $Λ_c (2880)$, $Ξ_c(3055)$, and $Ξ_c(3123)$.

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BibTeXRIS

A. Valcarce, H. Garcilazo, J. Vijande. 2008-07-18. Towards an understanding of heavy baryon spectroscopy. https://doi.org/10.1140/epja/i2008-10616-4

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