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A Model Distribution Function for Violently Relaxed N-Body Systems

  • N. Voglis
  • C. Efthymiopoulos
Conference paper

Abstract

A system of N particles collapsing under their collective self-gravity serves as a model to study galaxy formation from density inhomogeneities in the expanding universe. Such a system is being subject to a’violent relaxation’ towards a quasi-equilibrium state reached after a few dynamical times \( \tau_{d} = (G\bar{p})^{-1}, \bar{p} \) is the mean spatial density of particles). The violent relaxation is driven mainly by the rapid oscillations of the ’smooth’ self-gravitational potential ψ(r, t) derived by Poisson equation ∇2ψ(r, t)= 47π(r, t). During the potential oscillations the particles’ individual energy changes with time. A fraction of particles may acquire positive energies and escape. The rest form a bound configuration made of a tight ’core’ and a loose ’halo.

Keywords

Circular Orbit Violently Relax Radial Density Profile Constant Angular Momentum Model Distribution Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • N. Voglis
    • 1
  • C. Efthymiopoulos
    • 1
  1. 1.Department of AstronomyUniversity of Athens PanepistimiopolisAthensGreece

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