GW190814: Spin and Equation of State of a Neutron Star Companion
GW190814: Spin and Equation of State of a Neutron Star Companion
复制标题
DOI：
10.3847/1538-4357/abc421
复制
发表时间：
2020-07
期刊：
影响因子：
--
通讯作者：
A. Tsokaros;M. Ruiz;S. Shapiro
中科院分区：
文献类型：
--
作者：
A. Tsokaros;M. Ruiz;S. Shapiro
LIGO/Virgo最近发现了一个有一个黑洞和一个紧凑伴星的合并双星，引发了关于次级双星性质的争论，次级双星福尔斯落入所谓的质量间隙。在这里，我们探讨的假设，次级是一个中子星星（NS）的一些后果。我们表明，迄今可行的状态方程（EOSs），快速均匀旋转的具体例子可能既不是必要的一些EOSs，也不足以为其他解释存在的NS。从GW 170817得到的球形NS最大质量的绝对上限已经表明，这个未知的致密伴星可能是一个缓慢甚至不旋转的NS。然而，GW 170817所青睐的几个具有最大球形质量的软NS EOS不能用来解释这个物体，即使允许最大的均匀旋转。相比之下，足够坚硬的EOS产生的NS是缓慢旋转的，或者在某些情况下，不旋转，并与GW 170817和中子星星内部成分探测器（NICER）的结果兼容，可以解释黑洞伴侣。
The recent discovery by LIGO/Virgo of a merging binary having a black hole and a compact companion has triggered a debate regarding the nature of the secondary, which falls into the so-called mass gap. Here we explore some consequences of the assumption that the secondary was a neutron star (NS). We show with concrete examples of heretofore viable equations of state (EOSs) that rapid uniform rotation may neither be necessary for some EOSs nor sufficient for others to explain the presence of an NS. Absolute upper limits for the maximum mass of a spherical NS derived from GW170817 already suggest that this unknown compact companion might be a slowly or even a nonrotating NS. However, several soft NS EOSs favored by GW170817 with maximum spherical masses cannot be invoked to explain this object, even allowing for maximum uniform rotation. By contrast, sufficiently stiff EOSs that yield NSs that are slowly rotating or, in some cases, nonrotating, and are compatible with GW170817 and the results of the Neutron Star Interior Composition Explorer (NICER), can account for the black hole companion.