The edge of galaxy formation - II. Evolution of Milky Way satellite analogues after infall

Jonas Frings, Andrea Maccio, Tobias Buck, Camilla Penzo, Aaron Dutton, Marvin Blank, Aura Obreja

Research output: Contribution to journalArticle

Abstract

In the first paper, we presented 27 hydrodynamical cosmological simulations of galaxies with total masses between 5 × 108 and 1010 M. In this second paper, we use a subset of these cosmological simulations as initial conditions (ICs) for more than 40 hydrodynamical simulations of satellite and host galaxy interaction. Our cosmological ICs seem to suggest that galaxies on these mass scales have very little rotational support and are velocity dispersion (σ) dominated. Accretion and environmental effects increase the scatter in the galaxy scaling relations (e.g. size-velocity dispersion) in very good agreement with observations. Star formation is substantially quenched after accretion. Mass removal due to tidal forces has several effects: it creates a very flat stellar velocity dispersion profile, and it reduces the dark matter content at all scales (even in the centre), which in turn lowers the stellar velocity on scales around 0.5 kpc even when the galaxy does not lose stellar mass. Satellites which start with a cored dark matter profile are more prone to either be destroyed or to end up in a very dark matter poor galaxy. Finally, we found that tidal effects always increase the 'cuspyness' of the dark matter profile, even for haloes that infall with a core.

Original languageEnglish (US)
Pages (from-to)3378-3389
Number of pages12
JournalMonthly Notices of the Royal Astronomical Society
Volume472
Issue number3
DOIs
Publication statusPublished - Jan 1 2017

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Keywords

  • Cosmology: theory
  • Dark matter
  • Galaxies: formation
  • Galaxies: kinematics and dynamics
  • Methods: numerical

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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