Analytical Potential-Density Pairs for Flat Rings and Toroidal Structures
نویسندگان
چکیده
The Kuzmin-Toomre family of discs is used to construct potentialdensity pairs that represent flat ring structures in terms of elementary functions. Systems composed of two concentric flat rings, a central disc surrounded by one ring and a ring with a centre of attraction are also presented. The circular velocity of test particles and the epicyclic frequency of small oscillations about circular orbits are calculated for these structures. A few examples of three-dimensional potential-density pairs of “inflated” flat rings (toroidal mass distributions) are presented.
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تاریخ انتشار 2002