The effects of dynamical substructure on Milky Way mass estimates from the high-velocity tail of the local stellar halo

  title={The effects of dynamical substructure on Milky Way mass estimates from the high-velocity tail of the local stellar halo},
  author={Robert J. J. Grand and Alis J. Deason and Simon D. M. White and Christine M. Simpson and Facundo A. G'omez and Federico Marinacci and R{\"u}ediger Pakmor},
  journal={Monthly Notices of the Royal Astronomical Society: Letters},
We investigate the impact of dynamical streams and substructure on estimates of the local escape speed and total mass of Milky-Way-mass galaxies from modelling the high-velocity tail of local halo stars. We use a suite of high-resolution magnetohydrodynamical cosmological zoom-in simulations that resolve phase space substructure in local volumes around solar-like positions. We show that phase space structure varies significantly between positions in individual galaxies and across the suite… Expand

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