The Strength of the Dynamical Spiral Perturbation in the Galactic Disk

  title={The Strength of the Dynamical Spiral Perturbation in the Galactic Disk},
  author={Anna-Christina Eilers and David W. Hogg and Hans–Walter Rix and Neige Frankel and Jason A. S. Hunt and Jean-Baptiste Fouvry and Tobias Buck},
  journal={The Astrophysical Journal},
The mean Galactocentric radial velocities of luminous red giant stars within the midplane of the Milky Way reveal a spiral signature, which could plausibly reflect the response to a nonaxisymmetric perturbation of the gravitational potential in the Galactic disk. We apply a simple steady-state toy model of a logarithmic spiral to interpret these observations, and find a good qualitative and quantitative match. Presuming that the amplitude of the gravitational potential perturbation is… 

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    Monthly Notices of the Royal Astronomical Society
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