From young to old: spectral models for star cluster systems

Evolutionary synthesis models for star clusters of various metallicities, including gaseous emission during the lifetime of the ionizing stars, are used to model star cluster systems comprising two populations: an old metal-poor globular cluster (GC) population similar to that of the Milky Way halo, and a second GC population of arbitrary metallicity. We investigate the time evolution of color distributions and luminosity functions for the two GC populations and compare with observations of E/S0 galaxies. We show that multi-passband data for GC populations give clues to the relative ages and metallicities of the two subpopulations, and help constrain formation scenarios for their parent galaxies.