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arXiv · 1304.2121

Equation of state for neutron stars in SU(3) flavor symmetry

Tsuyoshi Miyatsu·Myung-Ki Cheoun·Koichi Saito
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Abstract

Using several relativistic mean field models (such as GM1, GM3, NL3, TM1, FSUGold and IU-FSU) as well as the quark-meson coupling model, we calculate the particle fractions, the equation of state, the maximum mass and radius of a neutron star within relativistic Hartree approximation. In determining the couplings of the isoscalar, vector mesons to the octet baryons, we examine the extension of SU(6) spin-flavor symmetry to SU(3) flavor symmetry. Furthermore, we consider the strange ($σ^{\ast}$ and $ϕ$) mesons, and study how they affect the equation of state. We find that the equation of state in SU(3) symmetry can sustain a neutron star with mass of $(1.8 \sim 2.1) M_{\odot}$ even if hyperons exist inside the core. In addition, the strange vector ($ϕ$) meson and the variation of baryon structure in matter also play important roles in supporting a massive neutron star.

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Tsuyoshi Miyatsu, Myung-Ki Cheoun, Koichi Saito. 2013-04-08. Equation of state for neutron stars in SU(3) flavor symmetry. https://doi.org/10.1103/physrevc.88.015802

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