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arXiv · hep-ph/9705438

Quark-antiquark resonances in the NJL model

V. Bernard·A. H. Blin·B. Hiller·Yu. P. Ivanov·A. A. Osipov·Ulf-G. Meißner
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Abstract

The problem of the $ρ$ meson resonance solution in the extended NJL model is studied. It has been shown previously that the solution for the $ρ$ meson changes smoothly from a bound state to a "virtual state" when the vector channel attraction becomes too weak to support bound state solutions. We have found that together with these solutions a separate resonance branch appears which is not connected smoothly with the bound state solutions. At small values of constituent quark mass, $m\sim 200$ MeV, it corresponds to the physical vector meson resonance solution in the quark-continuum region. The $a_1$ and $σ$ resonances are also discussed.

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V. Bernard, A. H. Blin, B. Hiller, Yu. P. Ivanov, A. A. Osipov, Ulf-G. Meißner. 1997-05-27. Quark-antiquark resonances in the NJL model. https://doi.org/10.1016/s0370-2693(97)00930-1

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