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arXiv · 1605.04839

Tetraquarks in the 1/N expansion and meson-meson resonances

L. Maiani·A. D. Polosa·V. Riquer
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Abstract

Diquarks are found to have the right degrees of freedom to describe the tetraquark poles in hidden-charm to open-charm meson-meson amplitudes. Compact tetraquarks result as intermediate states in non-planar diagrams of the 1/N expansion and the corresponding resonances are narrower than what estimated before. The proximity of tetraquarks to meson-thresholds has an apparent role in this analysis and, in the language of meson molecules, an halving rule in the counting of states is obtained.

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L. Maiani, A. D. Polosa, V. Riquer. 2016-06-08. Tetraquarks in the 1/N expansion and meson-meson resonances. https://doi.org/10.1007/jhep06(2016)160

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