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arXiv · 0811.1538

New biorthogonal potential--density basis functions

Alireza Rahmati·Mir Abbas Jalali
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Abstract

We use the weighted integral form of spherical Bessel functions, and introduce a new analytical set of complete and biorthogonal potential--density basis functions. The potential and density functions of the new set have finite central values and they fall off, respectively, similar to $r^{-(1+l)}$ and $r^{-(4+l)}$ at large radii where $l$ is the latitudinal quantum number of spherical harmonics. The lowest order term associated with $l=0$ is the perfect sphere of de Zeeuw. Our basis functions are intrinsically suitable for the modeling of three dimensional, soft-centred stellar systems and they complement the basis sets of Clutton-Brock, Hernquist & Ostriker and Zhao. We test the performance of our functions by expanding the density and potential profiles of some spherical and oblate galaxy models.

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Alireza Rahmati, Mir Abbas Jalali. 2008-11-10. New biorthogonal potential--density basis functions. https://doi.org/10.1111/j.1365-2966.2008.14226.x

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