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arXiv · 1212.1373

On the proliferation of X's, Y's and Z's candidates

A. Valcarce·T. F. Caramés·J. Vijande
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Abstract

Heavy meson spectroscopy above open flavor thresholds has become a challenge both from the experimental and theoretical points of view. Experimentally, several signals have been interpreted as meson resonances with unusual properties; theoretically, such signals may be identified with meson-meson molecules or compact multiquark structures. We analyze the influence of thresholds on heavy meson spectroscopy comparing different flavor sectors and quantum numbers. The validity of a quark-model picture above open-flavor thresholds would severely restrict the number of channels that may lodge multiquark structures as meson-meson molecules.

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A. Valcarce, T. F. Caramés, J. Vijande. 2012-12-06. On the proliferation of X's, Y's and Z's candidates. https://doi.org/10.1007/s00601-012-0518-8

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