标题： 双星在多星族球状星团中的演化 - II. 致密双星 显示英文标题

标题： Evolution of Binary Stars in Multiple-Population Globular Clusters - II. Compact Binaries

摘要： 我们介绍了对N体模拟的调查结果，旨在探讨多星族球状星团中紧密双星的演化。我们表明，由于第一代（FG）和第二代（SG）星族在结构特性上的初始差异以及动力学过程对双星的影响，SG双星比例比FG星族的比例减少得更快。 FG和SG双星比例之间的差异在定性上与我们在之前研究中发现的更宽双星的差异相似，但在定量上要小。双星比例的径向变化演化是由双星分选、电离和抛射之间的相互作用驱动的。 电离和抛射部分抵消了质量分选的影响，但对于紧凑双星来说，分选的影响占主导地位，因此在星团演化过程中内部双星比例增加。 我们探讨了FG和SG双星比例差异随距离星团中心的距离的变化，以及其与双星结合能和星团结构参数的关系。 我们在模拟中发现的FG和SG星族中双星比例的差异与观测研究的结果一致，这些研究发现SG星族的双星比例较小。 显示英文摘要

摘要： We present the results of a survey of N-body simulations aimed at exploring the evolution of compact binaries in multiple-population globular clusters.We show that as a consequence of the initial differences in the structural properties of the first-generation (FG) and the second-generation (SG) populations and the effects of dynamical processes on binary stars, the SG binary fraction decreases more rapidly than that of the FG population. The difference between the FG and SG binary fraction is qualitatively similar to but quantitatively smaller than that found for wider binaries in our previous investigations.The evolution of the radial variation of the binary fraction is driven by the interplay between binary segregation, ionization and ejection. Ionization and ejection counteract in part the effects of mass segregation but for compact binaries the effects of segregation dominate and the inner binary fraction increases during the cluster evolution. We explore the variation of the difference between the FG and the SG binary fraction with the distance from the cluster centre and its dependence on the binary binding energy and cluster structural parameters. The difference between the binary fraction in the FG and the SG populations found in our simulations is consistent with the results of observational studies finding a smaller binary fraction in the SG population.