RMxAA

Revista Mexicana de Astronomía y Astrofísica

ISSN: 3061-8649
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How to Cite

Violent Relaxation, Dynamical Instabilities and the Formation of Elliptical Galaxies. (1990). Revista Mexicana De Astronomía Y Astrofísica, 21(1), 89. https://astronomia.unam.mx/journals/rmxaa/article/view/1990rmxaa..21...89a

Abstract

: The problem of formation of elliptical galaxies via dissipationless collapse is studied using a large set of numerical simulations. It is shown that dissipationless collapses from cold initial conditions, where the total initial kinetic energy is less than 5% ofthe initial potential energy, lead to relaxed triaxial systems ery similar to real elliptical galaxies ii projected shape and density profiles. The triaxial shape is due to the of a dynamical instability that appears on systems dominated by radial orbits, while final density profile is due to violent relaxation that tends to produce a unique distribution iii space. These two phenomena erase memory of the initial prodtice a convergent evolution toward realistic systems, thus making unnecessary use o[special initial conditions (other than the condition ofbeing cold). Cold initial the radial orbits and large potential energy fluctuations necessary for both and are thus sufficient. KQ words: GALAXIES-DYNAMICS - GALAXIES-ELLIPTICAL - GALAXIES-FORMATION
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