Collapse in systems with attractive nonintegrable potentials - art. no. 210601

Collapse, or a gravitational-like phase transition, is found in microcanoni cal ensembles of particles with an attractive 1/r(alpha) potential not only for alpha = 1 but for all 0 < <alpha> < 3, The phase behavior of the syste m is complex: If an effective sufficiently short-range cutoff is applied, t he density of the collapsed phase is finite everywhere; if not, the collaps e results in a density singularity. Also, with increasing effective cutoff range, the gravitational phase transition will cross over to a normal first -order phase transition.