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Bulk viscosity due to kaons in color-flavor-locked quark matter

Mark G. Alford·Matt Braby·Sanjay Reddy·Thomas Schaefer
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Abstract

We calculate the bulk viscosity of color-superconducting quark matter in the color-flavor-locked (CFL) phase. We assume that the lightest bosons are the superfluid mode H and the kaons K0 and K+, and that there is no kaon condensate. We calculate the rate of strangeness-equilibrating processes that convert kaons into superfluid modes, and the resultant bulk viscosity. We find that for oscillations with a timescale of milliseconds, at temperatures T << 1 MeV, the CFL bulk viscosity is much less than that of unpaired quark matter, but at higher temperatures the bulk viscosity of CFL matter can become larger.

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Mark G. Alford, Matt Braby, Sanjay Reddy, Thomas Schaefer. 2007-09-05. Bulk viscosity due to kaons in color-flavor-locked quark matter. https://doi.org/10.1103/physrevc.75.055209

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