Do phase transitions survive binomial reducibility and thermal scaling?

Abstract

First order phase transitions are described in terms of the microcanonical and canonical ensemble, with special attention to finite size effects. Difficulties in interpreting a "caloric curve" are discussed. A robust parameter indicating phase coexistence (univariance) or single phase (bivariance) is extracted for charge distributions.Comment: 10 pages, TeX type, psfig, also available at http://csa5.lbl.gov/moretto/ps/lgm.ps, to appear in the Proceedings of the 1st Catania Relativistic Ion Studies: Critical Phenomena and Collective Observables, Acicastello, May 27-31, 199