The Evolution and Current State of Swift-Heavy-Ion Track Modeling

This paper briefly reviews the modeling approaches to the swift heavy ion (SHI) track formation. It presents a step-by-step derivation of the two-temperature model, highlighting its underlying assumptions and approximations. Special attention is given to identifying assumptions that fail under the typical SHI track conditions, and what methods currently exist to go beyond them. As an alternative to analytical approximations, a combined Monte Carlo- molecular dynamics model is demonstrated, outlining its basic assumptions, their justifications, and validations. Finally, the paper addresses bottlenecks of the current multiscale approach, its remaining weaknesses, and necessary further developments of the theory and models.