title: Ion-counting nanodosemeter with particle tracking capabilities.
abstract: An ion-counting nanodosemeter (ND) yielding the distribution of radiation-induced ions in a low-pressure gas within a millimetric, wall-less sensitive volume (SV) was equipped with a silicon microstrip telescope that tracks the primary particles, allowing correlation of nanodosimetric data with particle position relative to the SV. The performance of this tracking ND was tested with a broad 250 MeV proton beam at Loma Linda University Medical Center. The high-resolution tracking capability made it possible to map the ion registration efficiency distribution within the SV, for which only calculated data were available before. It was shown that tracking information combined with nanodosimetric data can map the ionisation pattern of track segments within 150 nm-equivalent long SVs with a longitudinal resolution of approximately 5 tissue-equivalent nanometers. Data acquired in this work were compared with results of Monte Carlo track structure simulations. The good agreement between 'tracking nanodosimetry' data acquired with the new system and simulated data supports the application of ion-counting nanodosimetry in experimental track-structure studies.
authors.affiliation: Loma Linda University Medical Center, 11175 Campus Street, Loma Linda, CA 92354, USA. vbashkirov@dominion.llumc.edu
authors.forename: V
authors.initials: V
authors.lastname: Bashkirov
authors.forename: R
authors.initials: R
authors.lastname: Schulte
authors.forename: A
authors.initials: A
authors.lastname: Breskin
authors.forename: R
authors.initials: R
authors.lastname: Chechik
authors.forename: S
authors.initials: S
authors.lastname: Schemelinin
authors.forename: G
authors.initials: G
authors.lastname: Garty
authors.forename: A
authors.initials: A
authors.lastname: Wroe
authors.forename: H
authors.initials: H
authors.lastname: Sadrozinski
authors.forename: B
authors.initials: B
authors.lastname: Grosswendt
mesh_terms: D004307:Dose-Response Relationship, Radiation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007477:Ions; D018499:Linear Energy Transfer; D008904:Miniaturization; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D011522:Protons; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D007477:Ions; D011522:Protons