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arXiv · 0805.1399

$δ$ meson effects on neutron stars in the modified quark-meson coupling model

Zhong-Ming Niu·Chun-Yuan Gao
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Abstract

The properties of neutron stars are investigated by including $δ$ meson field in the Lagrangian density of modified quark-meson coupling model. The $Σ^-$ population with $δ$ meson is larger than that without $δ$ meson at the beginning, but it becomes smaller than that without $δ$ meson as the appearance of $Ξ^-$. The $δ$ meson has opposite effects on hadronic matter with or without hyperons: it softens the EOSes of hadronic matter with hyperons, while it stiffens the EOSes of pure nucleonic matter. Furthermore, the leptons and the hyperons have the similar influence on $δ$ meson effects. The $δ$ meson increases the maximum masses of neutron stars. The influence of $(σ^*,ϕ)$ on the $δ$ meson effects are also investigated.

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Zhong-Ming Niu, Chun-Yuan Gao. 2008-05-09. $δ$ meson effects on neutron stars in the modified quark-meson coupling model. https://doi.org/10.1142/s0218301310016636

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