A Model for Phase Transition based on Statistical Disassembly of Nuclei at Intermediate Energies
Abstract
Consider a model of particles (nucleons) which has a two-body interaction which leads to bound composites with saturation properties. These properties are : all composites have the same density and the ground state energies of composites with k nucleons are given by -kW+\sigma k^{2/3} where W and \sigma are positive constants. W represents a volume term and \sigma a surface tension term. These values are taken from nuclear physics. We show that in the large N limit where N is the number of particles such an assembly in a large enclosure at finite temperature shows properties of liquid-gas phase transition. We do not use the two-body interaction but the gross properties of the composites only. We show that (a) the p-\rho isotherms show a region where pressure does not change as changes just as in Maxwell construction of a Van der Waals gas, (b) in this region the chemical potential does not change and (c) the model obeys the celebrated Clausius-Clapeyron relations. A scaling law for the yields of composites emerges. For a finite number of particles N (upto some thousands) the problem can be easily solved on a computer. This allows us to study finite particle number effects which modify phase transition effects. The model is calculationally simple. Monte-Carlo simulations are not needed.
Keywords
Cite
@article{arxiv.cond-mat/0607142,
title = {A Model for Phase Transition based on Statistical Disassembly of Nuclei at Intermediate Energies},
author = {G. Chaudhuri and S. Das Gupta and M. Sutton},
journal= {arXiv preprint arXiv:cond-mat/0607142},
year = {2009}
}
Comments
RevTex file, 21 pages, 5 figures