The “Building Blocks” of Stellar Halos

Date

2017

Authors

Oman, Kyle A.
Starkenburg, Else
Navarro, Julio F.

Journal Title

Journal ISSN

Volume Title

Publisher

Galaxies

Abstract

The stellar halos of galaxies encode their accretion histories. In particular, the median metallicity of a halo is determined primarily by the mass of the most massive accreted object. We use hydrodynamical cosmological simulations from the APOSTLE project to study the connection between the stellar mass, the metallicity distribution, and the stellar age distribution of a halo and the identity of its most massive progenitor. We find that the stellar populations in an accreted halo typically resemble the old stellar populations in a present-day dwarf galaxy with a stellar mass ~0.2–0.5 dex greater than that of the stellar halo. This suggests that had they not been accreted, the primary progenitors of stellar halos would have evolved to resemble typical nearby dwarf irregulars.

Description

Keywords

galaxy formation and evolution, stellar halo, numerical simulations

Citation

Oman, K.A., Starkenburg, E. & Navarro, J.F. (2017). The “Building Blocks” of Stellar Halos. Galaxies, 5(3), 33. https://doi.org/10.3390/galaxies5030033