title: Nanodosimetry-based quality factors for radiation protection in space.
abstract: Evaluation and monitoring of the cancer risk from space radiation exposure is a crucial requirement for the success of long-term space missions. One important task in the risk calculation is to properly weigh the various components of space radiation dose according to their assumed contribution to the cancer risk relative to the risk associated with radiation of low ionization density. Currently, quality factors of radiation both on the ground and in space are defined by national and international commissions based on existing radiobiological data and presumed knowledge of the ionization density distribution of the radiation field at a given point of interest. This approach makes the determination of the average quality factor ofa given radiation field a rather complex task. In this contribution, we investigate the possibility to define quality factors of space radiation exposure based on nanodosimetric data. The underlying formalism of the determination of quality factors on the basis of nanodosimetric data is described, and quality factors for protons and ions (helium and carbon) of different energies based on simulated nanodosimetric data are presented. The value and limitations of this approach are discussed.
authors.affiliation: Department of Radiation Medicine, Loma Linda University Medical Center, B121, 11234 Anderson Street, Loma Linda, CA 92354, USA. rschulte@dominion.llumc.edu
authors.forename: Reinhard W
authors.initials: RW
authors.lastname: Schulte
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Wroe
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Bashkirov
authors.forename: Guy Y
authors.initials: GY
authors.lastname: Garty
authors.forename: Amos
authors.initials: A
authors.lastname: Breskin
authors.forename: Rachel
authors.initials: R
authors.lastname: Chechik
authors.forename: Sergei
authors.initials: S
authors.lastname: Shchemelinin
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Gargioni
authors.forename: Bernd
authors.initials: B
authors.lastname: Grosswendt
authors.forename: Anatoly B
authors.initials: AB
authors.lastname: Rosenfeld
mesh_terms: D004249:DNA Damage; D006801:Humans; D018499:Linear Energy Transfer / Q000528:radiation effects; D011336:Probability; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000592:standards*; D011835:Radiation Protection / Q000592:standards*; D011874:Radiometry / Q000009:adverse effects / Q000592:standards*; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013026:Space Flight