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arXiv · 0806.4914

Bulk viscosity of superfluid hyperon stars

M. E. Gusakov·E. M. Kantor
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Abstract

We calculated bulk viscosity due to non-equilibrium weak processes in superfluid nucleon-hyperon matter of neutron stars. For that, the dissipative relativistic hydrodynamics, formulated in paper [1] for superfluid mixtures, was extended to the case when both nucleons and hyperons are superfluid. It was demonstrated that in the most general case (when neutrons, protons, Lambda, and Sigma^{-} hyperons are superfluid), non-equilibrium weak processes generate sixteen bulk viscosity coefficients, with only three of them being independent. In addition, we corrected an inaccuracy in a widely used formula for the bulk viscosity of non-superfluid nucleon-hyperon matter.

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M. E. Gusakov, E. M. Kantor. 2008-06-30. Bulk viscosity of superfluid hyperon stars. https://doi.org/10.1103/physrevd.78.083006

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