论文标题

低能核物理和全球中子星特性

Low-energy nuclear physics and global neutron star properties

论文作者

Carlson, Brett V., Dutra, Mariana, Lourenço, Odilon, Margueron, Jérôme

论文摘要

我们解决了低能核物理数据在约束中子星的全局特性中的作用的问题,例如,在密集物质中没有相变的情况下,在没有相变的情况下,质量,半径,角度,角动量和潮汐变形性。为此,我们评估了415个相对论平均场和非偏见的天际型相互作用的能力,以重现基态结合能,电荷半径和一组球形核的巨大单极共振。相互作用是根据它们描述这些特征的能力进行了分类的,我们表明,提供对称能量及其斜率之间的紧密相关性,提供$ n = z $和$ n \ ne z $ nuclei的核心(主要由电荷半径数据驱动)。另外,通过在$^{208} $ pb中施加从等速模拟状态和中子皮肤半径的约束,我们获得以下估计值:$ e_ {sym,2} = 31.8 \ pm 0.7 $ meV和$ l_ {sym {sym,2} = 58.1 = 58.1 \ pm 9.0 $ 9.0 $ mev。然后,我们分析了中子星特性的预测,我们发现1.4 $ m_ \ odot $中子星(NS)半径在12至14 km之间,对于“更好”的核相互作用。我们表明,i)核模型对低能核物理数据的更好再现仅影响规范质量中子星的全球性质,ii)对对称能量的实验约束是减少NS物质不确定性的最有效的能量。但是,由于需要约束的密度区域远高于有限核中的密度,因此最大的不确定性源自EDF的密度依赖性,而EDF的密度依赖性基本上是未知的。

We address the question of the role of low-energy nuclear physics data in constraining neutron star global properties, e.g., masses, radii, angular momentum, and tidal deformability, in the absence of a phase transition in dense matter. To do so, we assess the capacity of 415 relativistic mean field and non-relativistic Skyrme-type interactions to reproduce the ground state binding energies, the charge radii and the giant monopole resonances of a set of spherical nuclei. The interactions are classified according to their ability to describe these characteristics and we show that a tight correlation between the symmetry energy and its slope is obtained providing $N=Z$ and $N\ne Z$ nuclei are described with the same accuracy (mainly driven by the charge radius data). By additionally imposing the constraints from isobaric analog states and neutron skin radius in $^{208}$Pb, we obtain the following estimates: $E_{sym,2}=31.8\pm 0.7$ MeV and $L_{sym,2}=58.1\pm 9.0$ MeV. We then analyze predictions of neutron star properties and we find that the 1.4$M_\odot$ neutron star (NS) radius lies between 12 and 14 km for the "better" nuclear interactions. We show that i) the better reproduction of low-energy nuclear physics data by the nuclear models only weakly impacts the global properties of canonical mass neutron stars and ii) the experimental constraint on the symmetry energy is the most effective one for reducing the uncertainties in NS matter. However, since the density region where constraints are required are well above densities in finite nuclei, the largest uncertainty originates from the density dependence of the EDF, which remains largely unknown.

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