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arXiv · 1001.3169

Compact stars with a quark core within NJL model

C. H. Lenzi·A. S. Schneider·C. Providência·R. M. Marinho Jr
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Abstract

An ultraviolet cutoff dependent on the chemical potential as proposed by Casalbuoni {\it et al} is used in the su(3) Nambu-Jona-Lasinio model. The model is applied to the description of stellar quark matter and compact stars. It is shown that with a new cutoff parametrization it is possible to obtain stable hybrid stars with a quark core. A larger cutoff at finite densities leads to a partial chiral symmetry restoration of quark $s$ at lower densities. A direct consequence is the onset of the $s$ quark in stellar matter at lower densities and a softening of the equation of state.

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C. H. Lenzi, A. S. Schneider, C. Providência, R. M. Marinho Jr. 2010-01-18. Compact stars with a quark core within NJL model. https://doi.org/10.1103/physrevc.82.015809

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