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Gauge invariance of the color-superconducting gap on the mass shell

R. D. Pisarski·D. H. Rischke
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Abstract

The gap parameter for color superconductivity is expected to be a gauge invariant quantity, at least on the appropriate mass shell. Computing the gap to subleading order in the QCD coupling constant, g, we show that the prefactor of the exponential in 1/g is gauge dependent off the mass shell, and independent of gauge on the mass shell.

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R. D. Pisarski, D. H. Rischke. 2001-11-24. Gauge invariance of the color-superconducting gap on the mass shell. https://doi.org/10.1016/s0375-9474(02)00702-9

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