Abstract：
PURPOSE:A nanodosimeter is a type of detector which measures single ionizations in a small gaseous volume in order to obtain ionization cluster size probability distributions for characterization of radiation types. Working nanodosimeter detectors are usually bulky machines which require a lot of space. In this work, the authors present a compact ceramic nanodosimeter detector and report on first measurements of cluster size distributions of 5MeV alpha particles. METHODS:Single ionization measurements are achieved by applying a weak electric field to collect positive ions in a hole in a ceramic plate. Inside the ceramic plate, due to a strong electric field, the ions are accelerated and produce impact-ionizations. The resulting electron avalanche is detected in a read-out electrode. A bayesian unfolding algorithm is then applied to the experimentally obtained cluster size distributions to reconstruct the true cluster size distributions. RESULTS:Experimentally obtained cluster size distributions by the compact nanodosimeter detector are presented. The reconstructed cluster size distributions agreed well with Monte Carlo simulated cluster size distributions for small volumes (diameter = 2:5 nm). For larger volumes discrepancies between the reconstructed cluster size distributions and cluster size distributions from Monte Carlo simulations were observed. CONCLUSIONS:For the first time ionization cluster size probability distributions could be obtained by a small and compact nanodosimeter detector. This signifies the achievement of a critical step towards the wide application of nanodosimetric characterization of radiation types including in clinical environments.
journal_name
Med Physjournal_title
Medical physicsauthors
Vasi F,Schneider Udoi
10.1002/mp.14738subject
Has Abstractpub_date
2021-01-28 00:00:00eissn
0094-2405issn
2473-4209pub_type
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