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arXiv · astro-ph/0303529

The Importance of Dry and Mixed Mergers for Early-Type Galaxy Formation

Sadegh Khochfar·Andreas Burkert
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Abstract

We use semi-analytical modelling techniques to investigate the progenitor morphologies of present day ellipticals. We find that, independent of the environment, the fraction of mergers of bulge dominated galaxies (early-types) increases with time. The last major merger of bright present day ellipticals with $M_{B} \lesssim -21$ is preferentially between bulge dominated galaxies, while those with $ M_{B} \sim -20$ have mainly experienced last major mergers between a bulge dominated and a disk dominated galaxy. Independent of specific model assumptions, more than 50% of present day elliptical in clusters with $M_B \lesssim -18$ had last major mergers which are not of spirals as usually expected within the standard merger scenario.

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Sadegh Khochfar, Andreas Burkert. 2003-03-24. The Importance of Dry and Mixed Mergers for Early-Type Galaxy Formation. https://doi.org/10.1086/379845

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