The Galaxy Distribution Function from the 2MASS Survey

We determine the spatial distribution function of galaxies from a wide range of samples in the 2MASS survey. The results agree very well with the form of the distribution predicted by the theory of cosmological gravitational many-body galaxy clustering. On large scales we find a value of the clustering parameter b = 0.867 +/- 0.026, in agreement with b = 0.83 +/- 0.05 found previously for the Pisces-Perseus supercluster. We measure b(theta) as a function of scale, since this is a powerful test of the applicability of computer simulations. The results suggest that when galaxies clustered they were usually surrounded by individual, rather than by communal haloes.