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Effect of color superconductivity on the mass and radius of a quark star

Stefan B. Ruester·Dirk H. Rischke
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Abstract

We compare quark stars made of color-superconducting quark matter to normal-conducting quark stars. We focus on the most simple color-superconducting system, a two-flavor color superconductor, and employ the Nambu-Jona-Lasinio (NJL) model to compute the gap parameter and the equation of state. By varying the strength of the four-fermion coupling of the NJL model, we study the mass and the radius of the quark star as a function of the value of the gap parameter. If the coupling constant exceeds a critical value, the gap parameter does not vanish even at zero density. For coupling constants below this critical value, mass and radius of a color-superconducting quark star change at most by ca. 20% compared to a star consisting of normal-conducting quark matter. For coupling constants above the critical value mass and radius may change by factors of two or more.

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Stefan B. Ruester, Dirk H. Rischke. 2003-11-24. Effect of color superconductivity on the mass and radius of a quark star. https://doi.org/10.1103/physrevd.69.045011

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