It is anticipated from hierarchical clustering theory that there are scalingrelationships between halos over a wide range of mass. Observationally it canbe difficult to identify the markers that characterize these relationshipsbecause of the small numbers of visible probes and confusion from contaminantsin projection. Nonetheless, in favorable circumstances it is possible toidentify a very useful marker: the radius of the caustic at second turnaround.In a few favorable circumstances it is possible to identify the radius of firstturnaround, or zero velocity surface about a collapsed region. It will be shownthat specifically the radius of second turnaround scales as anticipated overthree orders of magnitude in mass from 10^12 to 10^15 M_sun. Halos arecharacterized by zones of dispersed velocities within the second turnaroundcaustic and zones of infall between the first and second turnaround radii. Theinner zone is populated in the majority by gas poor morphologies and the outerzone is populated in the majority by gas rich morphologies. The numbers ofdwarfs within the inner zone is roughly constant per unit halo mass.
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