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Backwards galaxy formation with only a few parameters

I. Ferreras·J. Silk
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Abstract

We present a simple phenomenological model of star formation in galaxies that describes the process with a set of a few parameters. The star formation efficiency and the fraction of gas and metals ejected in outflows are assumed to be the main drivers of star formation. The Tully-Fisher and the Faber-Jackson relations in different passbands are used as constraints in the analysis of disk and elliptical galaxies, respectively. We find that a steep correlation between efficiency and maximum rotation velocity is needed in disk systems, whereas elliptical galaxies can be explained by a high star formation efficiency, uncorrelated with the central velocity dispersion. Gas outflows are not important in disks, whereas a correlation of outflows with galaxy mass must be invoked in early-type galaxies to account for the observed colors.

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I. Ferreras, J. Silk. 2001-07-27. Backwards galaxy formation with only a few parameters. https://arxiv.org/abs/astro-ph/0107524

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