On the Fundamental Properties of Dynamically Hot Galaxies

Abstract

A two-component isothermal equilibrium model is applied to reproduce basic structural properties of dynamically hot stellar systems immersed in their massive dark haloes. The origin of the fundamental plane relation for giant ellipticals is naturally explained as a consequence of dynamical equilibrium in the context of the model. The existence of two galactic families displaying different behaviour in the luminosity--surface-brightness diagram is shown to be a result of a smooth transition from dwarfs, dominated by dark matter near the centre, to giants dominated by the luminous stellar component. The comparison of empirical scaling relations with model predictions suggests that probably a unique dissipative process was operating during the violent stage of development of stellar systems in the dark haloes, and the depth of the potential well controlled the observed luminosity of the resulting galaxies. The interpretation also provides some restrictions on the properties of dark haloes implied by the fundamental scaling laws.

9 pages, 7 PostScript figures, uses MNRaS LaTeX style file; accepted for publication in MNRaS (Aug 1996)

Cited by in corpus (6)

• Binding Energy and the Fundamental Plane of Globular Clusters
• Central mass-to-light ratios and dark matter fractions in early-type galaxies
• Two-Phased Intra-Cluster Medium in the Centaurus Cluster of Galaxies
• The Two-Component Virial Theorem and the Physical Properties of Stellar Systems
• Convective cores in galactic cooling flows
• Fundamental plane: dark matter and dissipation contributions