On the Formation of Extended Galactic Disks by Tidally Disrupted Dwarf Galaxies

  title={On the Formation of Extended Galactic Disks by Tidally Disrupted Dwarf Galaxies},
  author={J. Pe{\~n}arrubia and A. McConnachie and A. Babul},
  journal={The Astrophysical Journal},
We explore the possibility that extended disks, such as that recently discovered in M31, are the result of a single dwarf (109-1010 M☉) satellite merger. We conduct N-body simulations of dwarf NFW halos with embedded spheroidal stellar components on coplanar, prograde orbits in an M31-like host galaxy. As the orbit decays due to dynamical friction and the system is disrupted, the stellar particles relax to form an extended, exponential-disk-like structure that spans the radial range 30-200 kpc… Expand

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