Is the Flattening of Elliptical Galaxies Necessarily Due to Rotation?

A metallicity-flattening relation for dwarf elliptical galaxies

It is shown that bright cluster dwarf ellipticals follow a relation between metallicity and apparent flattening. Rounder dwarfs tend to be more metal-rich. The evidence is based on colour as well as spectroscopic line-strength data from the literature. The large scatter of dEs around the mean metallicity-luminosity relation, usually ascribed to large observational errors, turns out to be an ell...

Is AGN feedback necessary to form red elliptical galaxies ?

We have used the smoothed particle hydrodynamics (SPH) code GADGET-2 to simulate the formation of an elliptical galaxy in a group-size cosmological dark matter halo with mass Mhalo ≃ 3× 10 12 h −1 M⊙ at z = 0. The use of a stellar population synthesis model has allowed us to compute magnitudes, colours and surface brightness profiles. We have included a model to follow the growth of a central b...

Elliptical Galaxies

Modes of Elliptical Galaxies

Long lived modes of elliptical galaxies can existà la van Kampen. Specific systems may possess long lived oscillations which Landau damp on time scales longer than a Hubble time. Some physical processes such as a close encounter, tidal forces from a cluster or an orbiting satellite could preferentially excite a coherent mode. These may relate to the observed faint structure in elliptical galaxi...

Dynamics of elliptical galaxies.

Elliptical galaxies were once thought to be similar in their structure and dynamics to rotationally flattened bodies like stars. The discovery that elliptical galaxies rotate much more slowly than a fluid body with the same shape has led to a qualitative change in our understanding of the dynamics of these systems. It is now believed that elliptical galaxies are fully triaxial in shape. Self-co...