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Chiral phase transition in an extended NJL model with higher-order multi-quark interactions

Kouji Kashiwa·Hiroaki Kouno·Tomohiko Sakaguchi·Masayuki Matsuzaki·Masanobu Yahiro
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Abstract

The chiral phase transition is studied in an extended Nambu--Jona-Lasinio model with eight-quark interactions. Equations for scalar and vector quark densities, derived in the mean field approximation, are nonlinear and mutually coupled. The scalar-type nonlinear term hastens the restoration of chiral symmetry, while the scalar-vector mixing term makes the transition sharper. The scalar-type nonlinear term shifts the critical endpoint toward the values predicted by lattice QCD simulations and the QCD-like theory.

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Kouji Kashiwa, Hiroaki Kouno, Tomohiko Sakaguchi, Masayuki Matsuzaki, Masanobu Yahiro. 2006-08-31. Chiral phase transition in an extended NJL model with higher-order multi-quark interactions. https://doi.org/10.1016/j.physletb.2007.01.061

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