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arXiv · 1610.06435

Two-solar-mass hybrid stars: a two model description with the Nambu-Jona-Lasinio quark model

Renan Câmara Pereira·Pedro Costa·Constança Providência
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Abstract

Hybrid stars with a quark phase described by the Nambu$-$Jona-Lasinio model are studied. The hadron-quark model used to determine the stellar matter equation of state favors the appearance of quark matter: the coincidence of the deconfinement and chiral transitions and a low vacuum constituent quark mass. These two properties are essential to build equations of state that predict pure quark matter in the center of neutron stars. The effect of vector-isoscalar and vector-isovector terms is discussed, and it is shown that the vector-isoscalar terms are necessary to describe 2$M_\odot$ hybrid stars, and the vector-isovector terms result in larger quark cores and a smaller deconfinement density.

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Renan Câmara Pereira, Pedro Costa, Constança Providência. 2016-10-20. Two-solar-mass hybrid stars: a two model description with the Nambu-Jona-Lasinio quark model. https://doi.org/10.1103/physrevd.94.094001

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