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arXiv · hep-ph/9903281

QCD condensate contributions to the effective quark potential in a covariant gauge

Ivan Schmidt·Jian-Jun Yang
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Abstract

We discuss QCD condensate contributions to the gluon propagator both in the fixed-point gauge and in covariant gauges for the external QCD vacuum gluon fields with the conclusion that a covariant gauge is essential to obtain a gauge invariant QCD vacuum energy density difference and to retain the unitarity of the quark scattering amplitude. The gauge-invariant QCD condensate contributions to the effective one-gluon exchange potential are evaluated by using the effective gluon propagator which produces a gauge-independent quark scattering amplitude.

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Ivan Schmidt, Jian-Jun Yang. 1999-03-22. QCD condensate contributions to the effective quark potential in a covariant gauge. https://doi.org/10.1103/physrevd.60.114005

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