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arXiv · hep-ph/9806216

Chiral Symmetry Restoration in the Instanton Liquid at Finite Density

R. Rapp
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Abstract

The properties of the QCD partition function at finite chemical potential are studied within the instanton liquid model. It is shown that the density dependence of the quark-induced instanton-antiinstanton (I-A) interaction leads to the formation of topologically neutral I-A pairs ('molecules'), resulting in a first order chiral phase transition at a critical chemical potential $μ_q^c\simeq 310$ MeV. At somewhat higher densities ($μ_q\ge360$ MeV), the quark Fermi surface becomes instable with respect to diquark condensation (Cooper pairs) generating BCS-type energy gaps of order 50 MeV.

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R. Rapp. 1998-06-01. Chiral Symmetry Restoration in the Instanton Liquid at Finite Density. https://doi.org/10.1016/s0375-9474(98)00501-6

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