We present and compare the luminosity functions and the spatial density fields of galaxies of different morphological types drawn from the Center of Astrophysics redshift survey. The luminosity function varies as a function of morphology; for irregular and dwarf galaxies it is significantly steeper than for ellipticals and spirals. The density fields of galaxies of different morphological types are compared, and the statistical significance of observed differences are determined with the use of extensive Monte Carlo experiments. We find significant differences between the density fields of elliptical, spiral, and irregular galaxies, which exist well outside of cluster cores. Both ellipticals and spirals tend to be more clustered than irregular galaxies. The ellipticals are more concentrated than the spirals in the Virgo and Ursa Major clusters, but the overdensity of the Local Supercluster outside of the clusters is more pronounced in the spiral sample. The observed differences are not consistent with galaxies of all morphologies being drawn from a common density field. The possibility that these effects are partially due to systematic biases with distance in the morphological classifications of galaxies is discussed. These results are analyzed in the context of biasing models.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science
- Galaxies: fundamental parameters
- Galaxies: luminosity function, mass function
- Large-scale structure of universe