Comparative Morphology of Galactic Carbon Monoxide and Hydrogen
We compare here overall galactic characteristics derived from observations of the λ2.6-mm J = l→0 rotational transition of 12C0 with those derived from observations of the λ21-cm hyperfine transition of atomic hydrogen. The CO observations show that the cold, compressed component of the interstellar medium is confined to larger extent than the more diffuse HI gas to the inner Galaxy, is confined to a thinner layer, and is more clumpily distributed. The two tracers share the same overall kinematics, and both are relatively depleted at R < 4 kpc except in the galactic nucleus itself. Quantitative measures of the relative distributions have been derived. Several assumptions underlying these derivations have been verified by numerical experiments.
KeywordsInterstellar Medium Column Density Terminal Velocity Galactic Rotation Galactic Rotation Curve
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