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Mapping Deconfinement with a Compact Star Phase Diagram

H. Grigorian·D. Blaschke·G. Poghosyan
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Abstract

We have found correlations between properties of the equation of state for stellar matter with a phase transition at supernuclear densities and two characteristic features of a "phase diagram" for rotating compact stars in the angular velocity - baryon number plane: 1) the critical dividing line between mono- and two-phase star configurations and 2) the maximum mass line. The second line corresponds to the minimum mass function for black hole candidates whereas the first one is observable by a population statistics, e.g. for Z-sources in low-mass X-ray binaries. The observation of a population gap in the mass distribution for the latter is suggested as an astrophysical verification of the existence of a first order phase transition in QCD at high densities such as the deconfinement.

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H. Grigorian, D. Blaschke, G. Poghosyan. 2002-09-22. Mapping Deconfinement with a Compact Star Phase Diagram. https://doi.org/10.1016/s0375-9474(02)01513-0

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