OUR MILKY WAY AS A PURE-DISK GALAXY—A CHALLENGE FOR GALAXY FORMATION

@article{Shen2010OURMW,
  title={OUR MILKY WAY AS A PURE-DISK GALAXY—A CHALLENGE FOR GALAXY FORMATION},
  author={Juntai Shen and Robert Michael Rich and John Kormendy and Christian D. Howard and Roberto De Propris and Andrea M. Kunder},
  journal={The Astrophysical Journal Letters},
  year={2010},
  volume={720},
  pages={L72 - L76}
}
Bulges are commonly believed to form in the dynamical violence of galaxy collisions and mergers. Here, we model the stellar kinematics of the Bulge Radial Velocity Assay (BRAVA) and find no sign that the Milky Way contains a classical bulge formed by scrambling pre-existing disks of stars in major mergers. Rather, the bulge appears to be a bar seen somewhat end-on, as hinted from its asymmetric boxy shape. We construct a simple but realistic N-body model of the Galaxy that self-consistently… 

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