The radioisotope actinium-225(^(225)Ac)has been successfully used for targeted alpha therapy in preclinical and clinical applications because of its excellent nuclear characteristics.Medium-and high-energy proton-spal...The radioisotope actinium-225(^(225)Ac)has been successfully used for targeted alpha therapy in preclinical and clinical applications because of its excellent nuclear characteristics.Medium-and high-energy proton-spallation reactions on thorium are the most important methods for producing^(225)Ac.This study examines the possibility of producing^(225)Ac by irradiating thorium oxide with medium-energy protons.Thorium-oxide sheets were irradiated with 40-,50-,60-,70-,and 80-Me V protons on the Associated Proton-beam Experiment Platform(APEP)of the China Spallation Neutron Source(CSNS).The cross sections for the formation of^(225)Ac were measured using the activation method and offline gamma-ray spectrometric technique.The experimental results were compared with the existing data from EXFOR as well as the theoretical data from the TALYS-based evaluated nuclear-data library.Based on the experimental cross section and theoretical calculations,the production yield of^(225)Ac in the irradiated thorium targets was examined.The results showed that APEP can produce sufficient quantities of^(225)Ac for purification and clinical therapy.This work is the first measurement of proton-induced nuclearreaction cross sections at the CSNS APEP.展开更多
文摘在第四代反应堆的发展中,钍基反应堆(例如钍基熔盐堆)是其中一个重要的研究方向.由于钍的储量大等因素,利用中子诱发^(232)Th发生辐射俘获反应产生^(233)Th是钍基反应堆中的一个重要反应,用于产生易裂变核素^(233)U.本研究采用Monte Carlo方法,定义了一种评价靶材和中子利用效率的综合利用系数,利用多项式拟合得到了综合利用系数和靶材厚度关系,并考虑了不同入射中子数目的影响,最后得到进行此反应的靶材最佳厚度为(1.980±0.002) cm.
基金supported by the National Natural Science Foundation of China(No.12075135)the National Natural Science Foundation of China(No.12375127)。
文摘The radioisotope actinium-225(^(225)Ac)has been successfully used for targeted alpha therapy in preclinical and clinical applications because of its excellent nuclear characteristics.Medium-and high-energy proton-spallation reactions on thorium are the most important methods for producing^(225)Ac.This study examines the possibility of producing^(225)Ac by irradiating thorium oxide with medium-energy protons.Thorium-oxide sheets were irradiated with 40-,50-,60-,70-,and 80-Me V protons on the Associated Proton-beam Experiment Platform(APEP)of the China Spallation Neutron Source(CSNS).The cross sections for the formation of^(225)Ac were measured using the activation method and offline gamma-ray spectrometric technique.The experimental results were compared with the existing data from EXFOR as well as the theoretical data from the TALYS-based evaluated nuclear-data library.Based on the experimental cross section and theoretical calculations,the production yield of^(225)Ac in the irradiated thorium targets was examined.The results showed that APEP can produce sufficient quantities of^(225)Ac for purification and clinical therapy.This work is the first measurement of proton-induced nuclearreaction cross sections at the CSNS APEP.
