title: Radiological properties of nanocomposite Fricke gel dosimeters for heavy ion beams.
abstract: The radiological properties of nanocomposite Fricke gel (NC-FG) dosimeters prepared with different concentrations of nano-clay, perchloric acid and ferrous ions in deaerated conditions were investigated under carbon and argon ion beam irradiation covering a linear-energy-transfer (LET) range of 10 to 3000 eV/nm. We found that NC-FG exhibits radiological properties distinct from those of conventional Fricke gel. The radiation sensitivity of NC-FG is independent of the LET and is nearly constant even at very high LET (3000 eV/nm) values in the Bragg peak region of the argon ion beam. In addition, whereas conventional Fricke gel dosimeters only operate under acidic conditions, NC-FG dosimeters function under both acidic and neutral conditions. The radiation sensitivity decreases with decreasing nano-clay concentration in NC-FG, which indicates that the nano-clay plays a vital role in the radiation-induced oxidation of Fe(2.)
authors.affiliation: Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan maeyama@riken.jp.
authors.forename: Takuya
authors.initials: T
authors.lastname: Maeyama
authors.affiliation: Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Fukunishi
authors.affiliation: Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Kenichi L
authors.initials: KL
authors.lastname: Ishikawa
authors.affiliation: Department of Neurosurgery, Himon'ya Hospital, 2-9-5 Minami, Meguro-ku, Tokyo 152-0013, Japan Advanced Center for Computing and Communication, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Fukasaku
authors.affiliation: Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan.
authors.forename: Shigekazu
authors.initials: S
authors.lastname: Fukuda
mesh_terms: D002138:Calibration; D005782:Gels / Q000737:chemistry*; D020450:Heavy Ions; D053761:Nanocomposites / Q000737:chemistry*; D000072232:Radiation Dosimeters
chemical_list: D005782:Gels
keywords: Gel dosimeter; Ion beam; LET; Nanocomposite gel