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arXiv · 1303.0342

Tetraquark Mesons in Large $N$ Quantum Chromodynamics

Steven Weinberg
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Abstract

It is argued that exotic mesons consisting of two quarks and two antiquarks are not ruled out in quantum chromodynamics with a large number $N$ of colors, as generally thought. They can come in two varieties: short-lived tetraquarks with decay rates proportional to $N$, which would be unobservable if $N$ were sufficiently large, and long-lived tetraquarks with decay rates proportional to 1/N. The $f_0(500)$ and $f_0(980)$ may be examples of these two varieties of exotic mesons.

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Steven Weinberg. 2013-03-02. Tetraquark Mesons in Large $N$ Quantum Chromodynamics. https://doi.org/10.1103/physrevlett.110.261601

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