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ID: 742576.0, MPI für Astronomie / Publikationen_mpia
The edge of galaxy formation - I. Formation and evolution of MW-satellite analogues before accretion
Authors:
Date of Publication (YYYY-MM-DD):2017
Title of Journal:Monthly Notices of the Royal Astronomical Society
Volume:472
Issue / Number:2
Start Page:2356
End Page:2366
Audience:Not Specified
Abstract / Description:The satellites of the Milky Way and Andromeda represent the smallest galaxies we can observe in our Universe. In this series of papers we aim to shed light on their formation and evolution using cosmological hydrodynamical simulations. In this first paper we focus on the galaxy properties before accretion, by simulating twenty seven haloes with masses between $5\times 10^8$ and $10^{10} M_\odot$. Out of this set nineteen haloes successfully form stars, while eight remain dark. The simulated galaxies match quite well present day observed scaling relations between stellar mass, size and metallicity, showing that such relations are in place before accretion. Our galaxies show a large variety of star formation histories, from extended star formation periods to single bursts. As in more massive galaxies, large star formation bursts are connected with major mergers events, which greatly contribute to the overall stellar mass build up. The intrinsic stochasticity of mergers induces a large scatter in the stellar mass halo mass relation, up to two orders of magnitude. Despite the bursty star formation history, on these mass scales baryons are very ineffective in modifying the dark matter profiles, and galaxies with a stellar mass below $\approx 10^6 M_\odot$ retain their cuspy central dark matter distribution, very similar to results from pure N-body simulations.
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI fÃ¼r Astronomie
Identifiers:ISSN:0035-8711