2006/11/23 by Pieter Buyle, P. Buyle, C. Hunter +3 · 3 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Scientific Research and Discoveries #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2006.11343.x
published as Mon.Not.Roy.Astron.Soc.375:773-792,2007 · 21 pages, 15 figures, accepted for publication in MNRAS
arxiv created 2006/11/23 · openalex publication_date 2007/02/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
We present new analytical distribution functions for anisotropic spherical galaxies. They have the density profiles of the γ-models, which allow a wide range of central density slopes, and are widely used to fit elliptical galaxies and the bulges of spiral galaxies. Most of our models belong to two two-parameter families. One of these parameters is the slope γ of the central density cusp. The other allows a wide range of varying radial and tangential anisotropies, at either small or large radii. We give analytical formulas for their distribution functions, velocity dispersions, and the manner in which energy and transverse velocity are distributed between orbits. We also give some of their observable properties, including line-of-sight velocity profiles which have been computed numerically. Our models can be used to provide a useful tool for creating initial conditions for N-body and Monte Carlo simulations.