Geant4‐DNA example applications for track structure simulations in liquid water: A report from the Geant4‐DNA Project

TLDR

This report introduces Geant4‑DNA user applications for simulating track structures in liquid water and related physical quantities such as range, stopping power, and mean free path. The applications, available in the Geant4 Monte‑Carlo toolkit, are open‑access, described in detail, benchmarked against international recommendations (ICRU, MIRD), and illustrate the impact of different Geant4‑DNA physics models on electron interactions in liquid water. Using the latest physics model sets (option 4 and option 6) the applications achieve more accurate stopping powers, dose‑point kernels, and W‑values than the default option 2, and they serve as reference tools for Geant4‑DNA users.

Abstract

This Special Report presents a description of Geant4‐DNA user applications dedicated to the simulation of track structures (TS) in liquid water and associated physical quantities (e.g., range, stopping power, mean free path…). These example applications are included in the Geant4 Monte Carlo toolkit and are available in open access. Each application is described and comparisons to recent international recommendations are shown (e.g., ICRU, MIRD), when available. The influence of physics models available in Geant4‐DNA for the simulation of electron interactions in liquid water is discussed. Thanks to these applications, the authors show that the most recent sets of physics models available in Geant4‐DNA (the so‐called “option4” and “option 6” sets) enable more accurate simulation of stopping powers, dose point kernels, and W‐values in liquid water, than the default set of models (“option 2”) initially provided in Geant4‐DNA. They also serve as reference applications for Geant4‐DNA users interested in TS simulations.