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arXiv · 1207.6893

Ionization Cluster Size Distributions Created by Low Energy Electrons and Alpha Particles in Nanometric Track Segment in Gases

Aliaksandr Bantsar
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Abstract

The interaction of ionizing radiation with nanometric targets is a field of interest for many branches of science such as: radiology, oncology, radiation protection and nanoelectronics. A new experimental technique known as nanodosimetry has been developed for the qualitative as well as quantitative description of these types of interactions. The work presented here is a contribution to this development, namely by further improvement of the new experimental technique called the Jet Counter, originally developed at the Andrzej Sołtan Institute for Nuclear Studies. The Jet Counter is a unique device in the world for studying the interaction of low energy electrons with nanometer targets in the range 2-10 nm (in unit density). The basic experimental result is the frequency distribution of ionization cluster size produced by ionizing particles in a gaseous (nitrogen or propane) nanometric track segment. The first experimental data on the frequency distribution of ionization cluster size produced by low energy "single" electrons (100 eV - 2000 eV) in target cylinders of nitrogen (N2) 0.34 μg/cm2. in diameter are presented. New experimental data on the frequency distribution of ionization cluster size produced by 3.8 MeV α-particles in a target cylinder of nitrogen (N2) and propane gas (C3H8), ranging from 0.1 to 0.5 μg/cm2 in diameter are presented. Experimental results are compared with Monte Carlo simulations. A Bayesian analysis is applied for convoluting the measured spectra to the true cluster size distributions. New quantities characterizing the interaction of ionizing radiation with the nanometre level are proposed, namely - P1, M1 and F2. It has been shown that these quantities may substitute for the traditional (macro) dosimetric quantities.

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Aliaksandr Bantsar. 2012-07-30. Ionization Cluster Size Distributions Created by Low Energy Electrons and Alpha Particles in Nanometric Track Segment in Gases. https://arxiv.org/abs/1207.6893

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