STRUCTURE IN THE DISTRIBUTION OF SOUTHERN GALAXIES DESCRIBED BY THE DISTRIBUTION FUNCTION

We apply the gravitational quasi-equilibrium distribution function to probe the clustering in eight absolute diameter-limited subsamples of the SSRS (Southern Sky Redshift Survey) galaxies. This is the first application of the distribution function to a large three-dimensional sample. We find that the thermodynamic model proposed by Saslaw and Hamilton (1984) is a good fit to the three-dimensional distribution of the southern galaxies. The parameter b is scale-invariant in a scale range of about 5-12 h(-1) Mpc, below which the distribution approaches the Poisson limit. Also, there is a trend for b to approach the Poisson limit on larger scales. We also investigate morphological segregation and diameter segregation and find that these two effects are not independent. Spirals cluster more weakly than ellipticals and lenticulars if the face-on diameters of the galaxies are less than about 20 h(-1) kpc. Spirals with face-on diameters larger than about 20 h(-1) kpc, however, cluster more strongly than the ellipticals. We believe both of these results indicate the early conditions of galaxy formation and the subsequent evolution of galaxies.