Signals of critical behavior in fragmenting finite systems

By studying the disassembly of excited drops within the framework of the classical molecular dynamics (CMD) model, a critical review of observables which can give a signature of a critical behavior is performed. In particular we look at the normalized variance of the mass of the largest fragment (NVM) and to the intermittency signal (IS). It is found the NVM displays a maximum in the critical region for CEL ID and percolation models, while it is not triggered in "noncritical" data like the one resulting from the random partition model. On the other hand, the IS displays a maximum when events with a big fragment are mixed with events composed mainly of small clusters. [S0556-2813(99)00408-2].