EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH 3 November 1999 GEANT4 SIMULATION OF ENERGY LOSSES OF IONS

The algorithm for the simulation of energy losses of low energy ions is described. The details of its implementation in GEANT4 are discussed. The comparison of the simulation results with the experimental data is presented. 1 Introduction GEANT4[1] is a toolkit for Monte Carlo particle transport simulation for a wide range of applications, based on the Object Oriented technology. The GEANT4 model of electromagnetic interaction of protons with matter at low energies was discussed in detail in our previous publication [2]. Concerning fast ions with higher Z, q model for the simulation of energy losses of such ions is implemented in Geant4 [3]. In this report we describe a model devloped for the extension of GEANT4 electromagnetic interactions of ions down to lower kinetic energies. This extension is necessary for the precise simulation of the stopping of low energy ions in matter, required by various types of analysis. For example, in space applications, the increasing use of sensitive components has lead to a higher susceptibility to heavy ion-induced failures and operational interruptions. The growing prolonged presence of man in space, especially in the context of the new International Space Station, will mean an increased astronaut health hazard. In this context heavy ions are thought to be particularly harmful from cellular and DNA damage point of view. On the other hand, in the medical field heavy ions are used for irradiation treatment, and in this application very accurate knowledge is required of the ion range and stopping power at low energies. A wide range of other important uses for low-energy ion transport simulation is also foreseen.