Mass distribution in our Galaxy

  title={Mass distribution in our Galaxy},
  author={Ortwin Gerhard},
  journal={Space Science Reviews},
  • O. Gerhard
  • Published 7 March 2002
  • Physics
  • Space Science Reviews
This article summarizes recent work on the luminosity and mass distribution of the galactic bulge and disk, and on the mass of the Milky Way's dark halo. A new luminosity model consistent with the COBE NIR data and the apparent magnitude distributions of bulge clump giant stars has bulge/bar length of ≃3.5 kpc, axis ratios of 1:(0.3–0.4):0.3, and short disk scale-length (≃2.1 kpc). Gas-dynamical flows in the potential of this model with constant M/L fit the terminal velocities in 10° le|l|le50… 

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