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New Evolutionary Synthesis Tool for Modelling Young Star Clusters in Merging Galaxies

Peter Anders·Richard de Grijs·Uta Fritze - v. Alvensleben
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Abstract

Globular cluster systems (GCSs) are vital tools for investigating the violent star formation histories of their host galaxies. This violence could e.g. have been triggered by galaxy interactions or mergers. The basic observational properties of a GCS are its luminosity function and color distributions (number of clusters per luminosity resp. color bin). A large number of observed GCSs show bimodal color distributions, which, by comparison with evolutionary synthesis (ES) models, can be translated into bimodality in metallicity and/or age. An additional uncertainty comes into play when one considers extinction within the host galaxy. These effects can be disentangled either by obtaining spectroscopic data for the clusters or by imaging observations in at least four passbands. This allows us then to discriminate between various formation scenarios of GCSs, e.g. the merger scenario by Ashman & Zepf and the multi-phase collapse model by Forbes et. al.. Young and metal-rich star cluster populations are seen to form in interacting and merging galaxies. We analyse multi-wavelength broad-band observations of these young cluster systems provided by the ASTROVIRTEL project.

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Peter Anders, Richard de Grijs, Uta Fritze - v. Alvensleben. 2002-10-14. New Evolutionary Synthesis Tool for Modelling Young Star Clusters in Merging Galaxies. https://doi.org/10.1007/10857603_40

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