We consider transport properties of the hypernuclear matter in neutron star cores. In particular, we calculate the thermal conductivity, the shear viscosity, and the momentum transfer rates for np${\Sigma }^{-}\Lambda e\mu$ composition of dense matter in $\beta$–equilibrium for baryon number densities in the range 0.1–1 fm${}^{-3}$. The calculations are based on baryon interactions treated within the framework of the non-relativistic Brueckner-Hartree-Fock theory. Bare nucleon-nucleon (NN) interactions are described by the Argonne v18 phenomenological potential supplemented with the Urbana IX three-nucleon force. Nucleon-hyperon (NY) and hyperon-hyperon (YY) interactions are based on the NSC97e and NSC97a models of the Nijmegen group. We find that the baryon contribution to transport coefficients is dominated by the neutron one as in the case of neutron star cores containing only nucleons. In particular, we find that neutrons dominate the total thermal conductivity over the whole range of densities explored and that, due to the onset of ${\Sigma }^{-}$ which leads to the deleptonization of the neutron star core, they dominate also the shear viscosity in the high density region, in contrast with the pure nucleonic case where the lepton contribution is always the dominant one.

中文翻译：

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高超声速中子星核的传输系数

我们考虑中子星核心中超核物质的传输特性。特别地，我们计算了 np 的热导率、剪切粘度和动量传递率${\Sigma }^{-}\Lambda \mathrm{电子}\mu$ 致密物质的组成 $\beta$– 重子数密度在 0.1-1 fm 范围内的平衡${}^{-3}$. 计算基于在非相对论 Brueckner-Hartree-Fock 理论框架内处理的重子相互作用。裸核子-核子 (NN) 相互作用由 Argonne v18 现象学势势描述，并辅以 Urbana IX 三核子力。Nucleon-hyperon (NY) 和 hyperon-hyperon (YY) 相互作用基于 Nijmegen 组的 NSC97e 和 NSC97a 模型。我们发现重子对输运系数的贡献由中子 1 主导，就像在仅包含核子的中子星核的情况下一样。特别是，我们发现中子在所探索的整个密度范围内占总热导率的主导地位，并且由于${\Sigma }^{-}$ 这导致中子星核心的去轻子化，它们还支配着高密度区域的剪切粘度，这与轻子贡献始终占主导地位的纯核子情况相反。