English

Quark mean field model with pion and gluon corrections for $\Lambda,~\Xi^0$ hypernuclei and neutron stars

Nuclear Theory 2017-06-07 v1

Abstract

Properties of Λ, Ξ0\Lambda,~\Xi^0 hypernuclei and neutron stars are investigated in quark mean field model with pion and gluon corrections. Firstly, u, du, ~d, and ss quarks are confined by relativistic harmonic oscillator potentials to generate the baryons, like nucleon, Λ, Σ\Lambda, ~\Sigma, and Ξ\Xi hyperons. The effects of pion-quark coupling and one-gluon exchange are considered perturbatively. Then, the baryons interact with each other through exchanging σ, ω,\sigma, ~\omega, and ρ\rho mesons between quarks in hypernuclei and nuclear matter. The strengths of confinement potentials for u, d,u, ~d, and ss quarks are determined by the masses and radii of free baryons. The coupling constants between the quarks and mesons are fixed by the ground-state properties of several nuclei and single-hyperon potentials at nuclear saturation density, which arises three parameter sets for the coupling constants between mesons and quarks, named QMF-NK1S, QMF-NK2S, and QMF-NK3S. Compared to the results of previous quark mean field model without pion and gluon corrections, it is found that properties of Λ\Lambda hypernuclei, i.e. the single Λ\Lambda energies, are more consistent with the experimental observables. Properties of Ξ0\Xi^0 hypernuclei are also calculated and compared with the results in previous quark mean field model. With these three parameter sets, the neutron stars containing hyperons are investigated through solving the Tolman-Oppenheimer-Volkoff equation. Maximum masses of neutron stars approach 2.1M2.1M_\odot with hyperons and corresponding radii are around 1313 km.

Keywords

Cite

@article{arxiv.1704.08884,
  title  = {Quark mean field model with pion and gluon corrections for $\Lambda,~\Xi^0$ hypernuclei and neutron stars},
  author = {Xueyong Xing and Jinniu Hu and Hong Shen},
  journal= {arXiv preprint arXiv:1704.08884},
  year   = {2017}
}

Comments

25 pages, 9 figures, 5 tables, accepted to Phys. Rev. C