摘要
在过去的十余年中,对非对称核物质的对称能的研究无论从实验还是理论上都取得了较大的突破,这对中子结构及其物态方程的理解具有十分重要的意义。本研究将采用一个相对保守的对称能斜率范围(25 Me V<L<105Me V)来研究其对快速转动中子星性质的约束,这些性质包括:质量-半径关系、转动惯量、引力红移以及转动形变等。通过该对称能斜率的约束,发现典型中子星(M=1.4M⊙)的半径约束在10.28～13.43 km范围内,这与最近的相关观测相一致。如果观察发现了质量较小的毫秒脉冲星,则将为核物质的对称能较软提供有效的证据。另外还发现,对角动量的一致性可为快转中子星转动惯量的上限提供约束。最后,根据具有低质量伴星的双星EXO0748-676的红移观测,给出了该脉冲星的质量下限(>1.5M⊙)。
During the past decade, theoretical researches and terrestrial nuclear laboratory experiments have made impressive progresses on the researches of symmetry energy of the asymmetric nuclear matters, which is very important in understanding the equation of states and the structures of neutron stars. In this work, by making use of a conservative symmetry energy slope (SES) range (25 MeV<L<115 MeV), the constraints from the SES on the structures and properties of static and rapid rotating neutron stars are investigated. The constraint properties include the mass-radius relations, the moments of inertia, the redshift, the deformations of the rapid rotating stars, etc. According to the conservative SES range, it is shown that the radius of a canonical neutron star (with M=1.4M⊙) can be constrained in a region of 10.28～13.43 km, which is consistent with one of the latest constraints on the radius of neutron star in observations. It is also shown that if a sub-millisecond pulsar with a lighter stellar mass is observed in the future, then a softer SES of the asymmetric nuclear matters is preferred. The universal property of the angular momentum provides a way to obtain the upper limit of the moment of inertia of a rapid rotating neutron star with observed mass. Moreover, the results also can provide a constraint on the lower mass limit (>1.5M⊙) of pulsar in low-mass X-ray binary EXO0748-676 if the observed redshift of this star is from the polar direction.
出处
《原子核物理评论》
CAS
CSCD
北大核心
2015年第2期161-169,共9页
Nuclear Physics Review
基金
Natural Science Foundation of China(10947023,11275073,11205061)
Fundamental Research Funds for Central Universities(2013ZG0036)~~
关键词
对称能
中子星
自转
symmetry energy
neutron star
rotation
