A sample of field ellipticals

Author(s): Smith, RM; Martinez, VJ; Graham, MJ

Source: ASTROPHYSICAL JOURNAL  Volume: 617   Issue: 2   Pages: 1017-1021   DOI: 10.1086/425890   Part: 1   Published: DEC 20 2004

Using well-defined selection criteria derived from Zaritsky et al. applied to the LEDA galaxy catalog, we have constructed a sample of elliptical galaxies that can be taken to lie in the field. Such criteria can easily be applied to theoretical simulations for direct comparison with observations. The variation of the number of «isolated» ellipticals with selection criteria is also investigated. A preliminary study of the environment of the field ellipticals shows that, in the mean, they are surrounded by a population of dwarf galaxies, out to projected radii of at least 500 kpc, with a radial density profile of r(-0.6 +/- 0.2) and a luminosity function slope of alpha similar to -1.8. The results are compared and contrasted to the satellite population around isolated spiral galaxies.