CRITICAL EVOLUTION OF HOT VANDERWAALS DROPLETS

The dynamical evolution and fragmentation of a hot finite van der Waal s system is investigated in a classical molecular dynamics approach. I t is demonstrated that, under certain conditions determined mainly by the initial deposited energy, the fragmentation of rare-atom clusters exhibit a critical behavior. This behavior leaves its signatures in th e mass distributions and the conditional moments, as well as the scale d factorial moments of the produced fragments. The connection between the observed critical behavior and the second-order liquid-gas phase t ransition is investigated by employing Fisher's droplet model for the average fragment mass distributions, and performing Campi and intermit tency analysis for the correlation and fluctuation properties of the f ragment mass distributions. The size dependence of the signatures of c ritical behavior is discussed. (C) 1997 American Institute of Physics.