Exclusion statistics in a trapped two-dimensional Bose gas

We study the statistical mechanics of a two-dimensional Bose gas with a repulsive delta-function interaction, using a mean-field approximation. By a direct counting of states we establish that this model obeys exclusion statistics and is equivalent to an ideal exclusion-statistics gas. We also show that this result is consistent with a full quantum-mechanical treatment of a quasi-two-dimensional system.