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Cosmological Simulations of Galaxy Formation II: Matching the Observational Properties of Disk Galaxies

Fabio Governato·Beth Willman·Lucio Mayer
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Abstract

We used fully cosmological, high resolution N-body + SPH simulations to follow the formation of disk galaxies with a rotational velocity between 140 and 280 Km/sec in a Lambda CDM universe. The simulations include gas cooling, star formation, the effects of a uniform UV background and a physically motivated description of feedback from supernovae. The host dark matter halos have a spin and last major merger redshift typical of galaxy sized halos as measured in recent large scale N-Body simulations. Galaxies formed rotationally supported disks with realistic exponential scale lengths and fall on the I-band and baryonic Tully Fisher relations. The combination of UV background and SN feedback drastically reduced the number of visible satellites orbiting inside a Milky Way sized halo, bringing it fair agreement with observations. Feedback delays SF in small galaxies and more massive ones contain older stellar populations. The current star formation rates as a function of galaxy stellar mass are in good agreement with those measured by the SDSS.

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Fabio Governato, Beth Willman, Lucio Mayer. 2005-10-31. Cosmological Simulations of Galaxy Formation II: Matching the Observational Properties of Disk Galaxies. https://arxiv.org/abs/astro-ph/0511005

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