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Relativistic Faddeev approach to the NJL model at finite density

M. C. Birse·J. A. McGovern·S. Pepin·N. R. Walet
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Abstract

We study the nucleon solution of the relativistic Faddeev equation as a function of density in the framework of a generalized Nambu-Jona-Lasinio model. We truncate the interacting two-body channels to the scalar diquark channel, the coupling constant of which is treated as a parameter. A 3-momentum cut-off is used to regularize the model. The Faddeev equation is solved numerically using the methods developed by Tjon and others. At zero density the nucleon is bound only for unrealistically large values of the scalar coupling and this binding energy decreases quickly with increasing density.

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M. C. Birse, J. A. McGovern, S. Pepin, N. R. Walet. 1999-05-17. Relativistic Faddeev approach to the NJL model at finite density. https://arxiv.org/abs/nucl-th/9905032

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