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arXiv · hep-ph/0409116

Exploring the QCD phase diagram with compact stars

D. Blaschke·H. Grigorian·A. Khalatyan·D. N. Voskresensky
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Abstract

We investigate a nonlocal chiral quark model with separable 4-fermion interaction for the case of U(3) flavor symmetry and show that strange quark matter is unlikely to occur in a large enough volume of a compact star to entail remarkable observational consequences. The phase diagram in the two-flavor sector of such model has a critical end point of the line of first order chiral/deconfinement phase transitions on which a triple point marks the junction with the critical line for second order phase transitions to two-flavor color superconductivity (2SC) below T~80 MeV. Stable hybrid star configurations with large quark matter core in a color superconducting phase can exist. A consistent cooling phenomenology requires that all quark species be gapped, the minimal pairing gap of the order of 10 - 100 keV.

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D. Blaschke, H. Grigorian, A. Khalatyan, D. N. Voskresensky. 2004-09-09. Exploring the QCD phase diagram with compact stars. https://doi.org/10.1016/j.nuclphysbps.2004.12.021

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