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arXiv · nucl-th/0611030

Cold uniform matter and neutron stars in the quark-mesons-coupling model

Abstract

A new density dependent effective baryon-baryon interaction has been recently derived from the quark-meson-coupling (QMC) model, offering impressive results in application to finite nuclei and dense baryon matter. This self-consistent, relativistic quark-level approach is used to construct the Equation of State (EoS) and to calculate key properties of high density matter and cold, slowly rotating neutron stars. The results include predictions for the maximum mass of neutron star models, together with the corresponding radius and central density, as well the properties of neutron stars with mass of order 1.4 $M_\odot$. The cooling mechanism allowed by the QMC EoS is explored and the parameters relevant to slow rotation, namely the moment of inertia and the period of rotation investigated. The results of the calculation, which are found to be in good agreement with available observational data, are compared with the predictions of more traditional EoS. The QMC EoS provides cold neutron star models with maximum mass 1.9--2.1 M$_\odot$, with central density less than 6 times nuclear saturation density ($n_{0}= 0.16 {\rm fm}^{-3}$) and offers a consistent description of the stellar mass up to this density limit. In contrast with other models, QMC predicts no hyperon contribution at densities lower than $3n_0$, for matter in $β$-equilibrium. At higher densities, $Ξ^{-,0}$ and $Λ$ hyperons are present.

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BibTeXRIS

J. Rikovska-Stone, P. A. M. Guichon, H. H. Matevosyan, A. W. Thomas. 2006-11-09. Cold uniform matter and neutron stars in the quark-mesons-coupling model. https://doi.org/10.1016/j.nuclphysa.2007.05.011

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