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Neutron star cooling constraints for color superconductivity in hybrid stars

S. Popov·H. Grigorian·D. Blaschke
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Abstract

We apply the recently developed Log N - Log S test of compact star cooling theories for the first time to hybrid stars with a color superconducting quark matter core. While there is not yet a microscopically founded superconducting quark matter phase which would fulfill constraints from cooling phenomenology, we explore the hypothetical 2SC+X phase and show that the magnitude and density-dependence of the X-gap can be chosen to satisfy a set of tests: temperature - age (T - t), the brightness constraint, Log N - Log S, and the mass spectrum constraint. The latter test appears as a new conjecture from the present investigation.

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S. Popov, H. Grigorian, D. Blaschke. 2005-12-27. Neutron star cooling constraints for color superconductivity in hybrid stars. https://doi.org/10.1103/physrevc.74.025803

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