The Dynamics of Rich Clusters - II. Luminosity Functions

Abstract

Photographic photometry of 14 rich clusters of galaxies are examined, focusing on the luminosity functions of the galaxies. The individual luminosity functions are well fitted by Schechter functions with alpha = -1.25. The composite luminosity function of all 14 clusters is best fitted by a Schechter function with alpha = -1.21 and a characteristic magnitude of -20.02 in B(J) (H0 = 100 km/s). It is found that there is no variation of cluster luminosity functions with richness of Bautz-Morgan type. The composite luminosity function of high velocity dispersion clusters has a fainter magnitude than that of the low velocity dispersion clusters.