Abstract details

Using evolutionary population synthesis, we present integrated colours, integrated spectral energy distributions and spectral absorption-line indices defined by the Lick Observatory image dissector scanner (Lick/IDS) system, for an extensive set of instantaneous-burst binary stellar populations with interactions. By comparing the results for populations with and without interactions we show that inclusion of binary interactions makes the appearance of the population substantially bluer. This effect raises the derived age and metallicity of the metallicity of the population.