Radiaton damage cascades: Liquid droplet treatment of subcascade interactions

Starting from the radiation damage cascades, as obtained using the collision approximation, we derive the energy density deposited into the lattice by the primary knock-on atom. Assuming cascade core melting we follow the time evolution of the system by solving a simplified version of the heat equation. This procedure gives a thermodynamic description of the cascades that allows us to analyze the influence of the cascade geometry on parameters like ion mixing, life time and volume of the melt. This is done in an energy range which is not covered by more precise descriptions, such as as molecular dynamics (MD), representing then a useful technique to qualitatively evaluate the effects of radiation damage. (orig.)