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On the Analytic Structure of the Quark Self-Energy in Nambu-Jona- Lasinio Models

P. P. Domitrovich·H. Müther
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Abstract

The self-energy of quarks is investigated for various models which are inspired by the Nambu--Jona-Lasinio (NJL) model. Including, beyond the Hartree-Fock approximation, terms up to second-order in the quark interaction, the real and imaginary parts of scalar and vector components of the self-energy are discussed. The second-order contributions depend on the energy and momentum of the quark under consideration. This leads to solutions of the Dirac equation which are significantly different from those of a free quark or a quark with constant effective mass, as obtained in the Hartree-Fock approximation.

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P. P. Domitrovich, H. Müther. 1993-08-25. On the Analytic Structure of the Quark Self-Energy in Nambu-Jona- Lasinio Models. https://doi.org/10.1088/0954-3899%2F20%2F12%2F005

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