1997/04/10 by Christophe Pichon, C. Pichon, Pichon, C. +3
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9704089
21 pages, TeX, special macros: texsis; MNRAS, accepted for publication also available in postscipt format at ftp://www.astro.unibas.ch/~pichon/papers/
arxiv created 1997/04/10 · openalex publication_date 1997/04/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The method originally developed by Kalnajs for the numerical linear stability analysis of round galactic disks is implemented in the regimes of non-analytic transformations between position space and angle-action space, and of vanishing growth rates. This allows effectively any physically plausible disk to be studied, rather than only those having analytic transformations into angle-action space which have formed the primary focus of attention to date. The transformations are constructed numerically using orbit integrations in real space, and the projections of orbit radial actions on a given potential density basis are Fourier transformed to obtain a dispersion relation in matrix form. To verify the implementation, the fastest m=2 growth rates of the isochrone and the Kuzmin-Toomre disks are recovered, and the weaker m=2 modes are computed. The evolution of those growth rates as a function of the halo mass is also calculated, and some m=1 modes are derived as illustration.