The Vertical Structure of the Outer Milky Way H I Disk

  title={The Vertical Structure of the Outer Milky Way H I Disk},
  author={Evan S. Levine and Leo Blitz and Carl Heiles},
  journal={The Astrophysical Journal},
We examine the outer Galactic H i disk for deviations from the b ¼ 0 � plane by constructing maps of disk surface density, mean height, and thickness. We find that the Galactic warp is well described by a vertical offset plus two Fourier modes of frequency m ¼ 1 and 2, all of which grow with galactocentric radius. Adding the m ¼ 2m ode accounts for the large asymmetry between the northern and southern warps. We use a Morlet wavelet transform to investigate the spatial and frequency localization… Expand
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