Radiological characteristics of charged particle interactions in the first clay-nanoparticle dichromate gel dosimeter

7th International Conference on 3D Radiation Dosimetry

Taylor, M.L.^1,2 ; Maeyama, T.^3 ; Fukunishi, N.^3 ; Ishikawa, K.L.^4,5,6 ; Fukasaku, K.^4,7 ; Furuta, T.^9 ; Takagi, S.^4,8 ; Noda, S.^4,9 ; Himeno, R.^4,9 ; Fukuda, S.^10

RMIT University/School of Applied Sciences, Melbourne, VIC, Australia^1

Peter MacCallum Cancer Centre/Physical Sciences, Melbourne, VIC, Australia^2

RIKEN/Nishina Centre for Accelerator-Based Science, Wako, Japan^3

RIKEN/Computational Science Research Program, Wako, Japan^4

University of Tokyo/Department of Nuclear Engineering and Management, Graduate School of Engineering, Tokyo, Japan^5

University of Tokyo/Photon Science Centre, Graduate School of Engineering, Tokyo, Japan^6

Himon'ya Hospital, Department of Neurosurgery, Tokyo, Japan^7

University of Tokyo/Department of Mechanical Engineering, Graduate School of Engineering, Tokyo, Japan^8

RIKEN/Advanced Centre for Computing and Communication, Wako, Japan

(10) National Institute of Radiological Sciences/Research Centre for Charged Particle Therapy, Chiba, Japan^9

关键词: Clay nanoparticles;    Dose distributions;    Effective atomic number;    Electron interaction;    Ion interactions;    Mass densities;    Polymer gel dosimeter;    Water equivalence;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/444/1/012110/pdf
DOI  :  10.1088/1742-6596/444/1/012110

来源: IOP

【 摘 要 】

The incorporation of clay nanoparticles into gel dosimeters shows promise for significant diffusion reduction - but to what extent does the presence of the nano-clay influence charged particle interactions and, in particular, what is the impact on water equivalence? In this work, we quantify the radiological characteristics of electron, proton and carbon ion interactions in the RIKEN dichromate nanoclay gel and specifically evaluate the water equivalence over a broad energy range. Results indicate that the radiological properties are sufficiently representative of tissues that this low-diffusion gel could readily be used for validation of complex dose distributions. Electron and proton ranges are within 1 % of those in water. Mean effective atomic numbers for electron interactions in the range 10 keV - 10 GeV are within 1 % of those of water which, coupled with the similar mass density, ultimately means the overall impact on dose distributions is not great. The range of C6+ions in the nanoclay gel is closer to that of water (1values indicate an over-response at low doses.