We present a catalogue of 39 multiple-mergers found using the mergers catalogue of the Galaxy Zoo project for z<0.1 and compare them to corresponding semi-analytical galaxies from the Millennium Simulation. We estimate the (volume-limited) multi-merger fraction of the local Universe using our sample and find it to be at least two orders of magnitude less than binary-mergers - in good agreement with the simulations (especially the Munich group). We then investigate the properties of galaxies in binary- and multi-mergers (morphologies, colours, stellar masses and environment) and compare these results with those predicted by the semi-analytical galaxies. We find that multi-mergers favour galaxies with properties typical of elliptical morphologies and that this is in qualitative agreement with the models. Studies of multi-mergers thus provide an independent (and largely corroborating) test of the Millennium semi-analytical models.
@article{arxiv.1012.4214,
title = {Galaxy Zoo: Multi-Mergers and the Millennium Simulation},
author = {D. W. Darg and S. Kaviraj and C. J. Lintott and K. Schawinski and J. Silk and S. Lynn and S. Bamford and R. C. Nichol},
journal= {arXiv preprint arXiv:1012.4214},
year = {2015}
}