The luminosity function of globular clusters used as a distance indicator

Abstract

We report on the results of a study of the properties of the globular cluster luminosity function (GCLF) as a distance indicator, performed using the homogeneous data set provided by the ACS Virgo and Fornax Cluster Surveys. The relative Virgo-Fornax distance modulus derived from our study is systematically lower than the values derived by other distance indicators and in particular is 0.2mag lower than the value obtained by using surface brightness fluctuation measurements on the same data-set. Overall, the results discussed here indicate that the GCLF parameters vary continuously and systematically as a function of galaxy luminosity (i.e., mass) and may be influenced by the cluster environment as suggested by cosmological simulations. © Springer-Verlag Berlin Heidelberg 2012.