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Hybrid stars within a covariant, nonlocal chiral quark model

D. B. Blaschke·D. Gomez Dumm·A. G. Grunfeld·T. Klahn·N. N. Scoccola
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Abstract

We present a hybrid equation of state (EoS) for dense matter in which a nuclear matter phase is described within the Dirac-Brueckner-Hartree-Fock (DBHF) approach and a two-flavor quark matter phase is modelled according to a recently developed covariant, nonlocal chiral quark model. We show that modern observational constraints for compact star masses (M ~ 2 M_sun) can be satisfied when a small vector-like four quark interaction is taken into account. The corresponding isospin symmetric EoS is consistent with flow data analyses of heavy ion collisions and points to a deconfinement transition at about 0.55 fm^-3.

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D. B. Blaschke, D. Gomez Dumm, A. G. Grunfeld, T. Klahn, N. N. Scoccola. 2007-05-16. Hybrid stars within a covariant, nonlocal chiral quark model. https://doi.org/10.1103/physrevc.75.065804

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