Elastic properties of nuclear pasta in a fully three-dimensional geometry
Elastic properties of nuclear pasta in a fully three-dimensional geometry
复制标题
全三维几何结构中核面食的弹性特性
DOI：
10.1016/j.physletb.2023.137769
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Ying-Xun Zhang
中科院分区：
文献类型：
--
作者：
Cheng-Jun Xia;Toshiki Maruyama;Nobutoshi Yasutake;Toshitaka Tatsumi;Ying-Xun Zhang
在相对论平均场模型的框架下，考虑了反射对称的全三维几何结构，在大应变（ε = 0.5）下，对中子星星物质的弹性性质进行了较为真实的估计.我们的计算证实了假设库仑晶体的液滴相以上的中子滴密度，但并不工作在大密度，因为弹性常数被发现后，达到其峰值降低的有效性。同样，在不可压缩的液滴模型中推导出的解析公式在小密度下对棒相给出了很好的描述，这高估了较大密度下的弹性常数。对于板，由于忽略了板的厚度变化，液滴模型的解析公式与我们的数值估计在定性上一致，但在定量上不一致。通过对数值结果的拟合，引入阻尼因子对解析公式进行了改进。核对称能的影响，采用两个参数集，相应的对称能L= 41.34和89.39 MeV的斜率检查。即使考虑到多晶各向异性引起的不确定性，在L= 41.34和89.39 MeV下得到的中子星星物质的弹性性质也有明显的不同，从而导致不同中子星星活动的可探测性差异。
Realistic estimations on the elastic properties of neutron star matter are carried out with a large strain (ε≲ 0.5) in the framework of relativistic-mean-field model with Thomas-Fermi approximation, where various crystalline configurations are considered in a fully three-dimensional geometry with reflection symmetry. Our calculation confirms the validity of assuming Coulomb crystals for the droplet phase above neutron drip density, which nonetheless does not work at large densities since the elastic constants are found to be decreasing after reaching their peaks. Similarly, the analytic formulae derived in the incompressible liquid-drop model give excellent description for the rod phase at small densities, which overestimates the elastic constants at larger densities. For slabs, due to the negligence on the variations of their thicknesses, the analytic formulae from liquid-drop model agree qualitatively but not quantitatively with our numerical estimations. By fitting to the numerical results, these analytic formulae are improved by introducing dampening factors. The impacts of nuclear symmetry energy are examined adopting two parameter sets, corresponding to the slope of symmetry energy L= 41.34 and 89.39 MeV. Even with the uncertainties caused by the anisotropy in polycrystallines, the elastic properties of neutron star matter obtained with L= 41.34 and 89.39 MeV are distinctively different, results in detectable differences in various neutron star activities.
Voigt 近似中的中子星地壳：应力应变张量的一般对称性和有效剪切模量的通用估计
影响因子：
--
作者：
A. Chugunov
通讯作者：
A. Chugunov