A new method to derive star formation histories of galaxies from their star cluster distributions

Abstract

Star formation happens in a clustered way which is why the star cluster population of a particular galaxy is closely related to the star formation history of this galaxy. From the probabilistic nature of a mass function follows that the mass of the most massive cluster of a complete population, Mmax, has a distribution with the total mass of the population as a parameter. The total mass of the population is connected to the star formation rate (SFR) by the length of a formation epoch. Since due to evolutionary effects only massive star clusters are observable up to high ages, it is convenient to use this Mmax(SFR) relation for the reconstruction of a star formation history. The age distribution of the most massive clusters can therefore be used to constrain the star formation history of a galaxy. The method, including an assessment of the inherent uncertainties, is introduced with this contribution, while following papers will apply this method to a number of galaxies.