The masses and metallicities of stellar haloes reflect galactic merger histories

  title={The masses and metallicities of stellar haloes reflect galactic merger histories},
  author={Richard D’Souza and Eric F. Bell},
  journal={Monthly Notices of the Royal Astronomical Society},
  • R. D’Souza, E. Bell
  • Published 23 May 2017
  • Physics
  • Monthly Notices of the Royal Astronomical Society
There is increasing observational and theoretical evidence for a correlation between the metallicity and the mass of the stellar halo for galaxies with Milky Way-like stellar masses. Using the Illustris cosmological hydrodynamical simulations, we find that this relationship arises because a single massive massive progenitor contributes the bulk of the mass to the accreted stellar component as well as sets its metallicity. Moreover, in the Illustris simulations, this relationship extends over 3… 

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