A Sample of Field Ellipticals

نویسندگان

  • Rodney M. Smith
  • Matthew J. Graham
چکیده

Using well-defined selection criteria applied to the LEDA galaxy catalogue 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 and a luminosity function slope of α ∼ −1.8. The results are compared and contrasted to the satellite population around isolated spiral galaxies. Subject headings: galaxies: elliptical and lenticular — galaxies: clusters: general — surveys

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تاریخ انتشار 2003