The luminosity function of field galaxies

TL;DR

This paper generalizes Schmidt's method to construct the luminosity function of field galaxies, accounting for density dependence on distance, and analyzes the luminosity functions across different galaxy morphological types.

Contribution

It introduces a generalized method for luminosity function construction and provides detailed Schechter function fits for various galaxy types, highlighting differences in luminosity parameters.

Findings

The luminosity functions for all, elliptical, and lenticular galaxies fit Schechter functions in narrow magnitude ranges.

Spiral galaxies' luminosity functions fit Schechter functions over a wider magnitude range, with parameter variations across types.

The mean galaxy density is estimated at 0.127 Mpc^-3 across the studied volume.

Abstract

Schmidt's method for construction of luminosity function of galaxies is generalized by taking into account the dependence of density of galaxies from the distance in the near Universe. The logarithmical luminosity function (LLF) of field galaxies depending on morphological type is constructed. We show that the LLF for all galaxies, and also separately for elliptical and lenticular galaxies can be presented by Schechter function in narrow area of absolute magnitudes. The LLF of spiral galaxies was presented by Schechter function for enough wide area of absolute magnitudes: . Spiral galaxies differ slightly by parameter . At transition from early spirals to the late spirals parameter in Schechter function is reduced. The reduction of mean luminosity of galaxies is observed at transition from elliptical galaxies to lenticular galaxies, to early spiral galaxies, and further, to late spiral galaxies, in a bright end, . The completeness and the average density of samples of galaxies of different morphological types are estimated. In the range the mean number density of all galaxies is equal 0.127 Mpc-3.