Galactic Models with Massive Corona - Part Two - Galaxy
Abstract
A new multicomponent model of our Galaxy is presented. To scale this model, recent determinations of the Sun's distance to the galactic center, R0, and of the circular velocity at the Sun, V0, have been reviewed, and the values R0=8.5 kpc and V0=220 km s-1 have been accepted. From the literature data on the rotation of the Milky Way system and on velocity dispersions in its spheroidal populations, on the distribution of infrared luminosity in the central parts of the Galaxy and on volume densities of RR Lyrae stars, globular clusters and hydrogen gas have been collected. This observational information renders it possible to distinguish the following populations: a nucleus, a bulge, a halo, a disk, a young population and a massive corona. All these populations have been analyzed and their masses, harmonic mean radii and structural parameters have been derived. Special attention has been given to the determination of the mass of the corona. Comparison of our model descriptive functions with the observed ones shows that they represent observations with the mean deviation of about 11 percent. A brief comparison of the model with some earlier ones has been given. This reveals that our results are closest to those of Rohlfs and Kreitschmann (1981).
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1989
- Bibcode:
- 1989A&A...223...95H