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How the quark self-energy affects the color-superconducting gap

Qun Wang·Dirk H. Rischke
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Abstract

We consider color superconductivity with two flavors of massless quarks which form Cooper pairs with total spin zero. We solve the gap equation for the color-superconducting gap parameter to subleading order in the QCD coupling constant $g$ at zero temperature. At this order in $g$, there is also a previously neglected contribution from the real part of the quark self-energy to the gap equation. Including this contribution leads to a reduction of the color-superconducting gap parameter $\f_0$ by a factor $b_0'=\exp \big[ -(\p ^2+4)/8 \big]\simeq 0.177$. On the other hand, the BCS relation $T_c\simeq 0.57\f_0$ between $\f_0$ and the transition temperature $T_c$ is shown to remain valid after taking into account corrections from the quark self-energy. The resulting value for $T_c$ confirms a result obtained previously with a different method.

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Qun Wang, Dirk H. Rischke. 2001-10-05. How the quark self-energy affects the color-superconducting gap. https://doi.org/10.1103/physrevd.65.054005

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