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When the Transition Temperature in Color Superconductors is Not Like in BCS Theory

Andreas Schmitt·Qun Wang·Dirk H. Rischke
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Abstract

We study color superconductivity with $N_f=1,2,$ and 3 massless flavors of quarks. We present a general formalism to derive and solve the gap equations for condensation in the even-parity channel. This formalism shows that the leading-order contribution to the gap equation is unique for all color superconductors studied here, and that differences arise solely at the subleading order. We discuss a simple method to compute subleading contributions from the integration over gluon momenta in the gap equation. Subleading contributions enter the prefactor of the color-superconducting gap parameter. In the case of color-flavor and color-spin locking we identify further corrections to this prefactor arising from the two-gap structure of the quasiparticle excitations. Computing the transition temperature, $T_c$, where the color-superconducting condensate melts, we find that these contributions lead to deviations from the BCS behavior $T_c\simeq 0.57 ϕ_0$, where $ϕ_0$ is the magnitude of the zero-temperature gap at the Fermi surface.

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Andreas Schmitt, Qun Wang, Dirk H. Rischke. 2002-09-18. When the Transition Temperature in Color Superconductors is Not Like in BCS Theory. https://doi.org/10.1103/physrevd.66.114010

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