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Modern compact star observations and the quark matter equation of state

T. Klahn·D. Blaschke·F. Sandin·C. Fuchs·A. Faessler·H. Grigorian·G. Ropke·J. Trumper
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Abstract

We present a hybrid equation of state (EoS) for dense matter that satisfies phenomenological constraints from modern compact star (CS) observations which indicate high maximum masses (M = 2 M_sun) and large radii (R> 12 km). The corresponding isospin symmetric EoS is consistent with flow data analyses of heavy-ion collisions and a deconfinement transition at approx. 0.55 fm^{-3}. The quark matter phase is described by a 3-flavor Nambu--Jona-Lasinio model that accounts for scalar diquark condensation and vector meson interactions while the nuclear matter phase is obtained within the Dirac-Brueckner-Hartree-Fock (DBHF) approach using the Bonn-A potential. We demonstrate that both pure neutron stars and neutron stars with quark matter cores (QCSs) are consistent with modern CS observations. Hybrid star configurations with a CFL quark core are unstable.

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T. Klahn, D. Blaschke, F. Sandin, C. Fuchs, A. Faessler, H. Grigorian, G. Ropke, J. Trumper. 2007-11-20. Modern compact star observations and the quark matter equation of state. https://doi.org/10.1016/j.physletb.2007.08.048

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