Next: Transparency of the Stochastic Up: Model of the Galaxy Previous: Frequency distribution of galactic
One of the most detailed models of the structure of our Galaxy has been developed by Einasto (1979). It involves six components: nucleus, bulge, halo, disk, flat component and corona (see Table 12). The parameters of the model resulted from a numerical fitting of various data, such as the observed distribution of the young star population and neutral hydrogen, the density of population II stars in the vicinity of the Sun, the galactic rotation curve and the dynamics and distribution of globular clusters and dwarf irregular satellites of the Galaxy. The density of matter in the Galaxy is expressed as
r is the distance from the Galactic Center, z is the distance from the galactic plane.
Note that the huge mass of the corona that is evidenced by the motion of the dwarf satellites of the Galaxy, can hardly be fully comprised in stars. The fraction of stars in the corona is an important parameter for the models of gravitational radiation of the Galaxy: its variation would cause a significant change of gravitational radiation from the galactic polar regions, which are mostly populated by stars from the galactic corona.
Here, the fraction of stars in the corona is assumed to be percent. We note that future gravitational observations could suggest a way to determine the value of .