The Orbital Ellipticity of Satellite Galaxies and the Mass of the Milky Way

  title={The Orbital Ellipticity of Satellite Galaxies and the Mass of the Milky Way},
  author={Christopher Barber and Else Starkenburg and Julio F. Navarro and Alan W. McConnachie and Azadeh Fattahi},
  journal={Monthly Notices of the Royal Astronomical Society},
We use simulations of Milky Way-sized dark matter haloes from the Aquarius Project to investigate the orbits of substructure haloes likely, according to a semi-analytic galaxy formation model, to host luminous satellites. These tend to populate the most massive subhaloes and are on more radial orbits than the majority of subhaloes found within the halo virial radius. One reason for this (mild) kinematic bias is that many low-mass subhaloes have apocentres that exceed the virial radius of the… 

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