title: Distributions of deposited energy and ionization clusters around ion tracks studied with Geant4 toolkit.
abstract: The Geant4-based Monte Carlo model for Heavy-Ion Therapy (MCHIT) was extended to study the patterns of energy deposition at sub-micrometer distance from individual ion tracks. Dose distributions for low-energy (1)H, (4)He, (12)C and (16)O ions measured in several experiments are well described by the model in a broad range of radial distances, from 0.5 to 3000 nm. Despite the fact that such distributions are characterized by long tails, a dominant fraction of deposited energy (∼80%) is confined within a radius of about 10 nm. The probability distributions of clustered ionization events in nanoscale volumes of water traversed by (1)H, (2)H, (4)He, (6)Li, (7)Li, and (12)C ions are also calculated. A good agreement of calculated ionization cluster-size distributions with the corresponding experimental data suggests that the extended MCHIT can be used to characterize stochastic processes of energy deposition to sensitive cellular structures.
authors.affiliation: Frankfurt Institute for Advanced Studies (FIAS), Johann Wolfgang Goethe University, 60438 Frankfurt am Main, Germany. Deutsches Krebsforschungszentrum (DKFZ), 69120 Heidelberg, Germany.
authors.forename: Lucas
authors.initials: L
authors.lastname: Burigo
authors.forename: Igor
authors.initials: I
authors.lastname: Pshenichnov
authors.forename: Igor
authors.initials: I
authors.lastname: Mishustin
authors.forename: Gerhard
authors.initials: G
authors.lastname: Hilgers
authors.forename: Marcus
authors.initials: M
authors.lastname: Bleicher
mesh_terms: D003198:Computer Simulation; D063193:Heavy Ion Radiotherapy / Q000379:methods* / Q000592:standards; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D012984:Software