title: Study on patient-induced radioactivity during proton treatment in hengjian proton medical facility.
abstract: At present, increasingly more proton medical facilities have been established globally for better curative effect and less side effect in tumor treatment. Compared with electron and photon, proton delivers more energy and dose at its end of range (Bragg peak), and has less lateral scattering for its much larger mass. However, proton is much easier to produce neutron and induced radioactivity, which makes radiation protection for proton accelerators more difficult than for electron accelerators. This study focuses on the problem of patient-induced radioactivity during proton treatment, which has been ignored for years. However, we confirmed it is a vital factor for radiation protection to both patient escort and positioning technician, by FLUKA's simulation and activation formula calculation of Hengjian Proton Medical Facility (HJPMF), whose energy ranges from 130 to 230MeV. Furthermore, new formulas for calculating the activity buildup process of periodic irradiation were derived and used to study the relationship between saturation degree and half-life of nuclides. Finally, suggestions are put forward to lessen the radiation hazard from patient-induced radioactivity.
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Qingbiao
authors.initials: Q
authors.lastname: Wu
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Qingbin
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China; China Spallation Neutron Source (CSNS), Institute of Physics (IPHY), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China.
authors.forename: Tianjiao
authors.initials: T
authors.lastname: Liang
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Zhang
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Yinglin
authors.initials: Y
authors.lastname: Ma
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Rong
authors.initials: R
authors.lastname: Ye
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Qiongyao
authors.initials: Q
authors.lastname: Liu
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Yufei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
authors.forename: Huaibao
authors.initials: H
authors.lastname: Wang
mesh_terms: D006207:Half-Life; D006801:Humans; D009502:Neutrons; D011522:Protons; D011835:Radiation Protection; D011851:Radioactivity
chemical_list: D011522:Protons
keywords: Activation; Buildup; FLUKA; Induced radioactivity; O-15; Patient; Proton; Saturation degree; dose