| Abstract | The total population and spatial distribution of globular clusters associated with the edge-on S0 galaxy NGC 3115, derived from star counts carried out upon Canada-France-Hawaii-Telescope and Anglo-Australian Telescope prime focus plates is described. The cluster system is of specific frequency S about equal to 2, somewhat below normal for an E/S0 galaxy, but consistent with its location in a sparse environment. The spatial distribution of the globular clusters is similar to that describing the falloff of halo luminosity along the galaxy's minor axis. The cluster distribution exhibits circular symmetry within the observational errors, suggesting that the globular clusters are a more nearly pure halo component of NGC 3115 than any part of its very prominent disk or extended spheroid light. A preliminary integrated luminosity function is derived by combining star counts from several sources and a distance in the range of 8-12 Mpc is deduced. Finally, a nucleated dwarf companion of NGC 3115 which itself has a globular cluster system is identified. Furthermore, the dwarf has more clusters per unit luminosity (by a factor near 3) than its parent galaxy NGC 3115; in this respect the system resembles the Fornax dwarf spheroidal as a satellite of the Milky Way galaxy. |
