Orbital Decay of Satellite Galaxies in Spherical Systems
Orbital Decay of Satellite Galaxies in Spherical Systems
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球形系统中卫星星系的轨道衰变
DOI：
10.1086/163785
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
M. Weinberg
中科院分区：
文献类型：
--
作者：
M. Weinberg
本文根据适用于球形系统的动力学摩擦理论，考虑了在球形母星系中运动的矮卫星的轨道衰减率，其中轨道是在给定的球势U（r）中精确确定的。球面理论避免了拉塞卡理论（CT）中存在的阻力发散，其结果可视为确定CT中出现的拟动力因子。对于一个由普卢默定律模拟的矮星系，其核心半径为γ（r sub s），在半径为r sub s的奇异等温球中沿圆形轨道运动，对数因子为ln λ = ln（0.75/gamma），对应于p-max = 1.2（r sub s）。计算了球体对卫星的响应密度（卫星尾流），并与无限均匀情况下的尾流进行了比较。15篇参考文献。
The orbital-decay rate of a dwarf satellite moving in a spherical parent galaxy is considered on the basis of a theory of dynamical friction applicable to spherical systems, in which the orbits are determined exactly in a given spherical potential U(r). The spherical theory avoids the drag-force divergence that exists in Chandrasekhar's theory (CT), and the results may be regarded as determining the logarithimic factor appearing in CT. For a dwarf galaxy modeled by a Plummer law with a core radius gamma(r sub s) moving in a circular orbit in a singular isothermal sphere at radius r sub s, the logarithmic factor is ln Lambda = ln (0.75/gamma), corresponding to p-max = 1.2(r sub s). The response density of the sphere to the satellite (the satellite wake) is computed and compared with the wake in the infinite homogeneous case. 15 references.