论文标题
恒星多样性的热力学：在密集的恒星环境中二元星种群的动态演变
The thermodynamics of stellar multiplicity: dynamical evolution of binary star populations in dense stellar environments
论文作者
论文摘要
最近，我们使用态近似密度近似，分析分布函数得出了直接单二元散射的结果（Stone＆Leigh 2019）。使用这些结果分布函数，我们在本文中介绍了使用Boltzmann方程的Fokker-Planck极限获得的基于统计力学的分析模型。我们的模型量化了主要的引力物理学，结合了强和弱的单二元相互作用，从而驱动了密集的恒星环境中二元轨道参数分布的时间演变。我们特别关注二元轨道能和偏心率的分布。我们发现了二元偏心率的新型稳态分布，具有最高和最低偏心二进制的强大耗竭。在能量空间中，我们将分析模型的预测与数值N体模拟的结果进行了比较，并发现该一致性对此处考虑的初始条件有益。这项工作是迈向开发完全自洽的半分析模型的第一步，该模型是由于直接的几岁相互作用而在密集的恒星环境中动态发展的二元星人群。
We recently derived, using the density-of-states approximation, analytic distribution functions for the outcomes of direct single-binary scatterings (Stone & Leigh 2019). Using these outcome distribution functions, we present in this paper a self-consistent statistical mechanics-based analytic model obtained using the Fokker-Planck limit of the Boltzmann equation. Our model quantifies the dominant gravitational physics, combining both strong and weak single-binary interactions, that drives the time evolution of binary orbital parameter distributions in dense stellar environments. We focus in particular the distributions of binary orbital energies and eccentricities. We find a novel steady state distribution of binary eccentricities, featuring strong depletions of both the highest and the lowest eccentricity binaries. In energy space, we compare the predictions of our analytic model to the results of numerical N-body simulations, and find that the agreement is good for the initial conditions considered here. This work is a first step toward the development of a fully self-consistent semi-analytic model for dynamically evolving binary star populations in dense stellar environments due to direct few-body interactions.
