论文标题
研究中子星形白矮人二进制中的传质的稳定性
Investigating the stability of mass transfer in neutron star-helium white dwarf binaries
论文作者
论文摘要
中子星形白矮人（NS+He WD）二进制是近距离二进制恒星系统的重要进化产物。通常将它们视为毫秒脉冲星，并且可能会继续演变为超紧凑的X射线二进制文件（UCXB）和连续的重力波（GW）源，这些源将由太空传播GW观测值（例如Lisa，Tianqin和Taiji）检测到。然而，NS+HE WD二进制经历的稳定性并未得到很好的研究，并且仍在辩论中。在本文中，我们对NS+HE WD二进制文件的演变进行建模，其中WD质量为0.17-0.45 $ M _ {\ odot} $，应用详细的恒星进化代码MESA。与以前基于流体动力学的研究相反，我们发现所有NS+He WD二进制物显然都经历了稳定的传质。对于这样的UCXB，我们发现WD质量越大，最大质量转移速率越大，并且在进化过程中的最小轨道周期越小。最后，我们在数值和分析上证明了WD质量和GW频率之间的相关性与NS质量无关。
Neutron star-helium white dwarf (NS+He WD) binaries are important evolutionary products of close-orbit binary star systems. They are often observed as millisecond pulsars and may continue evolving into ultra-compact X-ray binaries (UCXBs) and continuous gravitational wave (GW) sources that will be detected by space-borne GW observatories, such as LISA, TianQin and Taiji. Nevertheless, the stability of NS+He WD binaries undergoing mass transfer is not well studied and still under debate. In this paper, we model the evolution of NS+He WD binaries with WD masses ranging from 0.17-0.45 $M_{\odot}$, applying the detailed stellar evolution code mesa. Contrary to previous studies based on hydrodynamics, we find that apparently all NS+He WD binaries undergo stable mass transfer. We find for such UCXBs that the larger the WD mass, the larger the maximum mass-transfer rate and the smaller the minimum orbital period during their evolution. Finally, we demonstrate numerically and analytically that there is a tight correlation between WD mass and GW frequency for UCXBs, independent of NS mass.
