Star formation history of resolved galaxies. I. The Method

Abstract

We present a new method to determine the star formation and metal enrichment histories of any resolved stellar system. This method is based on the fact that any observed star in a colour-magnitude diagram will have a certain probability of being associated with an isochrone characterised by an age t and metallicity [Fe/H] (i.e. to have formed at the time and with the metallicity of that isochrone). We formulate this as a maximum likelihood problem that is then solved with a genetic algorithm. We test the method with synthetic simple and complex stellar populations. We also present tests using real data for open and globular clusters. We are able to determine parameters for the clusters (t, [Fe/H]) that agree well with results found in the literature. Our tests on complex stellar populations show that we can recover the star formation history and age-metallicity relation very accurately. Finally, we look at the history of the Carina dwarf galaxy using deep BVI data. Our results compare well with what we know about the history of Carina.

Accepted for publication in MNRAS. Version with high-resolution figures available at http://www.astro.ljmu.ac.uk/~dfb/Data/small_v1.3.pdf. Corrected typos and references. Changed figure 15

References in corpus (9)

• The Star Formation & Chemical Evolution History of the Sculptor Dwarf Spheroidal Galaxy
• Complexity on Small Scales III: Iron and alpha Element Abundances in the Carina Dwarf Spheroidal Galaxy
• A Large Stellar Evolution Database for Population Synthesis Studies. III. Inclusion of the full Asymptotic Giant Branch phase and Web tools for stellar population analyses
• Distance Scale Zero-Points from Galactic RR Lyrae Star Parallaxes
• Reaching the End of the White Dwarf Cooling Sequence in NGC 6791
• VLT/FLAMES spectroscopy of Red Giant Branch stars in the Carina dwarf spheroidal galaxy
• Deep MMT Transit Survey of the Open Cluster M37 I: Observations and Cluster Parameters
• A robust statistical estimation of the basic parameters of single stellar populations. I. Method
• The Carina Project. V. The impact of NLTE effects on the iron content

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