Characterization of the relationship between neutron production and thermal load on a target material in an accelerator-based boron neutron capture therapy system employing a solid-state Li target

Autoři: Satoshi Nakamura aff001;  Hiroshi Igaki aff002;  Masashi Ito aff004;  Hiroyuki Okamoto aff001;  Shie Nishioka aff001;  Kotaro Iijima aff001;  Hiroki Nakayama aff001;  Mihiro Takemori aff001;  Shoji Imamichi aff002;  Tairo Kashihara aff003;  Kana Takahashi aff003;  Koji Inaba aff003;  Kae Okuma aff003;  Naoya Murakami aff003;  Yoshihisa Abe aff002;  Yuko Nakayama aff003;  Mitsuko Masutani aff002;  Teiji Nishio aff009;  Jun Itami aff001
Působiště autorů: Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan aff001;  Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan aff002;  Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan aff003;  Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan aff004;  Department of Radiological Science, Graduate School of Human Health Sciences, Arakawa-ku, Tokyo, Japan aff005;  Lab of Collaborative Research, Division of Cellular Signaling, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan aff006;  Department of Radiological Technology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan aff007;  Center for Bioinformatics and Molecular Medicine, Department of Frontier Life Sciences, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto, Nagasaki, Japan aff008;  Department of Medical Physics, Graduate School of Medicine, Tokyo Women’s Medical University, Shinjuku-ku, Tokyo, Japan aff009
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0225587


An accelerator-based boron neutron capture therapy (BNCT) system that employs a solid-state Li target can achieve sufficient neutron flux derived from the 7Li(p,n) reaction. However, neutron production is complicated by the large thermal load expected on the target. The relationship between neutron production and thermal load was examined under various conditions. A target structure for neutron production consists of a Li target and a target basement. Four proton beam profiles were examined to vary the local thermal load on the target structure while maintaining a constant total thermal load. The efficiency of neutron production was evaluated with respect to the total number of protons delivered to the target structure. The target structure was also evaluated by observing its surface after certain numbers of protons were delivered. The yield of the sputtering effect was calculated via a Monte Carlo simulation to investigate whether it caused complications in neutron production. The efficiency of neutron production and the amount of damage done depended on the proton profile. A more focused proton profile resulted in greater damage. The efficiency decreased as the total number of protons delivered to the target structure increased, and the rate of decrease depended on the proton profile. The sputtering effect was not sufficiently large to be a main factor in the reduction in neutron production. The proton beam profile on the target structure was found to be important to the stable operation of the system with a solid-state Li target. The main factor in the rate of reduction in neutron production was found to be the local thermal load induced by proton irradiation of the target.

Klíčová slova:

Nucleons – Protons – Thermometers – Radioactivity – Particle accelerators – Boron – Gamma rays


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Článek vyšel v časopise


2019 Číslo 11