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arXiv · 1512.04497

Towards a Theoretical Understanding of the XYZ Mesons from QCD

Eric Braaten
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Abstract

The XYZ mesons are mesons that contain a heavy quark and antiquark but have properties that seem to require additional constituents. Some of them are electrically charged, so they must be tetraquark mesons whose additional constituents are a light quark and antiquark. The list of XYZ mesons has grown to about two dozen over the last decade. A promising approach to understanding these mesons within QCD is the Born-Oppenheimer approximation, which reduces the problem to the solution of the Schrodinger equation in potentials that can be calculated using lattice QCD. The Born-Oppenheimer approximation has not yet revealed the pattern of the XYZ mesons, but it provides a compelling framework for understanding them from the fundamental theory.

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Eric Braaten. 2015-12-14. Towards a Theoretical Understanding of the XYZ Mesons from QCD. https://doi.org/10.1051/epjconf%2F201611301015

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