3D view on Virgo and field dwarf elliptical galaxies: late-type origin and environmental transformations

TL;DR

This study uses integral-field spectroscopy to explore how environmental factors influence the morphology, kinematics, and stellar populations of dwarf elliptical galaxies in the Virgo cluster and the field, suggesting a late-type origin.

Contribution

It provides the first large-scale spectroscopic data for dwarf ellipticals, supporting their origin from dwarf spirals/irregulars and examining environmental effects on their properties.

Findings

dEs resemble fast-rotating giant early-type galaxies

No correlation between rotational support and cluster location

Dark matter fraction increases with distance from Virgo center

Abstract

We show the effects of environmental evolution on Virgo cluster and field dwarf elliptical galaxies (dEs), presenting the first large-scale integral-field spectroscopic data for this galaxy class. The great variety of morphological, kinematic, and stellar population parameters seen in our data supports the claim that dEs are defunct dwarf spiral/irregular galaxies and points to a formation scenario that allows for a stochastic shaping of galaxy properties. We further investigate the properties of our sample by analyzing its kinematic and dynamical properties. We compare the level of rotational support of dEs and giant early-type galaxies and show that the properties of the former largely resemble those of giant fast-rotators. Based on our data, no trend exists between the level of rotational support in dEs and their location in the cluster. However, a tentative trend is seen in dark matter fraction: it increases for larger Virgocentric distances.