A Sample of Field Ellipticals (original) (raw)

A SEARCH FOR CLOSE DWARF COMPANIONS OF ELLIPTICAL GALAXIES

It is found that the mean number of dwarf companions within a projected distance of 75 kpc from each of a sample of 34 isolated giant elliptical galaxies is, in a statistical sense, +0.12 ± 0.42 (95% confidence interval). Comparison is made with the results of Holmberg (1969) for a similar survey of 115 spiral galaxies in which the mean number of dwarf companions was found to be 4-1.08 ± 0.37. We argue that these values differ by a significant amount and that differences in sample selection and other procedures would be likely, if anything, to increase the difference. Finally, we speculate on the possible reasons why elliptical galaxies have fewer, smaller, or intrinsically less luminous dwarf companions than spirals.

A Population of Compact Elliptical Galaxies Detected with the Virtual Observatory

Science, 2009

Elliptical Galaxy Evolution Our closest elliptical galaxy, M32, represents a rare class of elliptical galaxies that are too compact for their luminosities. Only a handful of elliptical galaxies with luminosities and sizes comparable to M32 have been found, making it difficult to understand how they evolved. Chilingarian et al. (p. 1379 , published online 1 October) present a sample of 21 compact elliptical galaxies gathered through automated data mining of the Hubble Space Telescope Legacy Archive and other databases by means of virtual observatory tools. The results suggest that tidal stripping of more massive progenitor galaxies produces compact elliptical galaxies.

Identification and properties of isolated field elliptical galaxies from CFHTLS-W1

Publications of the Astronomical Society of Australia

We present a catalogue of isolated field elliptical (IfE) galaxies drawn from the W1 field of the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). 228 IfEs were identified from a flux-limited$(r<21.8)$galaxy catalogue which corresponds to a density of 3 IfE/sq.deg. For comparison we consider a sample of elliptical galaxies living in dense environments, based on identification of the brightest cluster galaxies (BGCs) in the same survey. Using the same dataset for the comparison sample ensures a uniform selection, including in the redshift range as IfEs (i.e.$0.1