标题： 具有相等质量的各向异性球状星系相遇中的轨道衰减 显示英文标题

标题： Orbit decay in encounters between anisotropic spherical galaxies of equal mass

摘要： 我们研究了径向各向异性对相同球状星系抛物线相遇时轨道衰减率的影响。 我们的星系模型具有赫尔尼奎斯特密度分布和奥斯波夫特-梅里特速度分布。 我们发现，径向各向异性模型的合并时间仅为各向同性模型的一半。 各向异性模型更容易受到潮汐变形的影响；这加速了轨道角动量向内部自由度的转移。 即使在初始接近阶段，各向异性模型也变得更加扭曲，并且在近日点时已经失去了大量的角动量。 我们的结果可能对合并率估计以及潮汐尾部的持久性产生影响。 显示英文摘要

摘要： We investigate the effect of radial anisotropy on the rate of orbit decay in parabolic encounters of identical spherical galaxies. Our galaxy models have Hernquist density profiles and Osipkov--Merritt velocity distributions. We find that radially anisotropic models merge in as little as half the time of their isotropic counterparts. Anisotropic models are more susceptible to tidal deformation; this accelerates the transfer of orbital angular momentum to internal degrees of freedom. Even during the initial approach, the anisotropic models become more distorted, and arrive at pericentre already having lost substantial amounts of angular momentum. Our results may have implications for estimates of merger rates and persistence of tidal tails.