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arXiv · 0901.2371

Hadronic Spectrum - Multiquark States

Stephen L. Olsen
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Abstract

Many newly discovered mesons behave like $\ccbar$ charmonium states in that they preferentially decay into final states that contain a $c$- and a $\bar{c}$-quark, but do not fit expectations for any of the unfilled levels of the conventional $\ccbar$ spectrum. There is a growing suspicion that at least some of these states are {\it exotic}, {\it i.e.} have a substructure that is more complex than the quark-antiquark mesons of the classical constituent quark model. Some of these candidate states have a non-zero electric charge and, thus, a minimal quark content of $\ccbar u\bar{d}$ or $\ccbar d\bar{u}$. In addition, states with similar properties have been observed in the $b$- and $s$-quark sectors. In this report, the experimental situation is briefly reviewed.

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Stephen L. Olsen. 2009-01-16. Hadronic Spectrum - Multiquark States. https://doi.org/10.1016/j.nuclphysa.2009.05.018

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