First order phase transition of expanding matter and its fragmentation

Using an expanding matter model with a Lennard-Jones potential, the instability of the expanding system is investigated. The pressure, temperature, and density fluctuations are calculated as functions of density during the time evolution of the expanding matter, which are compared to the coexistence curve calculated by the Gibbs ensemble. The expanding matter undergoes the first order phase transition in the limit of the quasistatic expansion. The resultant fragment mass distributions are also investigated