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arXiv · hep-ph/9407336

A nonlocal, covariant generalisation of the NJL model

R. D. Bowler·M. C. Birse
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Abstract

We solve a nonlocal generalisation of the NJL model in the Hartree approximation. This model has a separable interaction, as suggested by instanton models of the QCD vacuum. The choice of form factor in this interaction is motivated by the confining nature of the vacuum. A conserved axial current is constructed in the chiral limit of the model and the pion properties are shown to satisfy the Gell-Mann--Oakes--Renner relation. For reasonable values of the parameters the model exhibits quark confinement.

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R. D. Bowler, M. C. Birse. 1994-07-20. A nonlocal, covariant generalisation of the NJL model. https://doi.org/10.1016/0375-9474(94)00481-2

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