The Exotic XYZ Charmonium-like Mesons

Abstract

Charmonium, the spectroscopy of c\bar{c} mesons, has recently enjoyed a renaissance with the discovery of several missing states and a number of unexpected charmonium-like resonances. The discovery of these new states has been made possible by the extremely large data samples made available by the B-factories at the Stanford Linear Accelerator Center and at KEK in Japan, and at the CESR e^+e^- collider at Cornell. Conventional c\bar{c} states are well described by quark potential models. However, many of these newly discovered charmonium-like mesons do not seem to fit into the conventional c\bar{c} spectrum. There is growing evidence that at least some of these new states are exotic, i.e. new forms of hadronic matter such as mesonic-molecules, tetraquarks, and/or hybrid mesons. In this review we describe expectations for the properties of conventional charmonium states and the predictions for molecules, tetraquarks and hybrids and the various processes that can be used to produce them. We examine the evidence for the new candidate exotic mesons, possible explanations, and experimental measurements that might shed further light on the nature these states.

28 pages, 7 figures. Review for Ann Rev Nucl & Part Sci

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Cited by in corpus (14)

• Higher Charmonia and X,Y,Z states with Screened Potential
• Hadro-Charmonium
• Hadronic molecule structure of the Y(3940) and Y(4140)
• Implications of heavy quark spin symmetry on heavy meson hadronic molecules
• On the scattering of D and D* mesons off the X(3872)
• The bound state problem of S-wave heavy quark meson-aitimeson systems
• X(3872) and the bound state problem of $D^0{\bar{D}}^{\ast 0}$ (${\bar{D}}^0{D}^{\ast 0}$) in a chiral quark model
• Relativistic model of hidden bottom tetraquarks
• Mass spectrum of the vector hidden charm and bottom tetraquark states
• Holographic Hadro-Quarkonium
• Possible tetraquark states in the ${\pi }^{+}{\chi }_{c1}$ invariant mass distribution
• Diresonance in production and scattering of heavy mesons
• Exotic c c-bar Mesons
• The Charm Renaissance: D-Physics - a Selective Review