Model for radial dependence of frequency distributions for energy impartedin nanometer volumes from HZE particles

Citation
Fa. Cucinotta et al., Model for radial dependence of frequency distributions for energy impartedin nanometer volumes from HZE particles, RADIAT RES, 153(4), 2000, pp. 459-468
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Experimental Biology
Journal title
RADIATION RESEARCH
ISSN journal
0033-7587 → ACNP
Volume
153
Issue
4
Year of publication
2000
Pages
459 - 468
Database
ISI
SICI code
0033-7587(200004)153:4<459:MFRDOF>2.0.ZU;2-0
Abstract
This paper develops a deterministic model of frequency distributions for en ergy imparted (total energy deposition) in small volumes similar to DNA mol ecules from high-energy ions of interest for space radiation protection and cancer therapy. Frequency distributions for energy imparted are useful for considering radiation quality and for modeling biological damage produced by ionizing radiation. For high-energy ions, secondary electron (delta-ray) tracks originating from a primary ion track make dominant contributions to energy deposition events in small volumes. Our method uses the distributio n of electrons produced about an ion's path and incorporates results from M onte Carlo simulation of electron tracks to predict frequency distributions for ions, including their dependence on radial distance, The contribution from primary ion events is treated using an impact parameter formalism of s patially restricted linear energy transfer (LET) and energy-transfer stragg ling, We validate our model by comparing it directly to results from Monte Carlo simulations for proton acid or-particle tracks. We show for the first time frequency distributions of energy imparted in DNA structures by sever al high-energy ions such as cosmic-ray iron ions. Our comparison with resul ts from Monte Carlo simulations at low energies indicates the accuracy of t he method. (C) 2000 by Radiation Research Society.