Simple three-integral scale-free galaxy models

被引:47
作者
Evans, NW [1 ]
Hafner, RM [1 ]
deZeeuw, PT [1 ]
机构
[1] STERREWACHT LEIDEN,NL-2300 RA LEIDEN,NETHERLANDS
关键词
celestial mechanics; stellar dynamics; galaxies; kinematics and dynamics galaxies; structure;
D O I
10.1093/mnras/286.2.315
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The Jeans equations give the second moments or stresses required to support a stellar population against a gravity field. A general solution of the Jeans equations for arbitrary axisymmetric scale-free densities in flattened scale-free potentials is given. A two-parameter subset of the solution for the second moments for the self-consistent density of the power-law models, which have exactly spheroidal equipotentials, is examined in detail, In the spherical limit, the potential of these models reduces to that of the singular power-law spheres. We build the physical three-integral distribution functions that correspond to the flattened stellar components. Next, we attack the problem of finding distribution functions associated with the Jeans solutions in flattened scale-free potentials, The third or partial integral introduced by de Zeeuw, Evans & Schwarzschild for Binney's model is generalized to thin and near-thin orbits moving in arbitrary axisymmetric scale-free potentials. The partial integral is a modification of the total angular momentum. For the self-consistent power-law models, we show how this enables the construction of simple three-integral distribution functions. The connection between these approximate distribution functions and the Jeans solutions is discussed in some detail.
引用
收藏
页码:315 / 328
页数:14
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