Dynamical Effects of Cold Dark Matter Subhalos on a Galactic Disk

  title={Dynamical Effects of Cold Dark Matter Subhalos on a Galactic Disk},
  author={Hirohito Hayashi and Masashi Chiba},
  journal={Publications of the Astronomical Society of Japan},
We investigate the dynamical interaction between a galactic disk and surrounding numerous dark subhalos as expected for a galaxy-sized halo in the cold dark matter (CDM) models. Our particular interest is to what extent accretion events of subhalos into a disk are allowed in light of the observed thinness of a disk. Several models of subhalos are considered in terms of their internal density distribution, mass function, and spatial and velocity distributions. Based on a series of N-body… 

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