Nuclear and radiochemical study of production and utilization of radioactive astatine isotopes in the Li + Pb reaction

Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Maeda, Eita*; Yamada, Norihiro*; Makii, Hiroyuki   ; Watanabe, Shigeki; Ishioka, Noriko; Hashimoto, Kazuyuki

An radioactive nuclide At with a half-life of 7.2 h is a prospective candidate for utilization in targeted alpha radiotherapy. In a general way, At is produced through the Bi(,2n)At reaction. However, the nuclear reactions using lithium ion beams provide the possible production routes of At. Therefore, we have measured excitation functions of At isotopes in the reaction of 29-57 MeV Li + Pb at the tandem accelerator of JAEA-Tokai. The cross sections of radioactive products were determined by - and -ray spectrometry. The experimental excitation functions of astatine isotopes have been compared with a statistical calculation to study the reaction mechanism. Besides, a chemical separation of carrier-free radioactive astatine isotopes from an irradiated target has been studied with a dry-chemistry method. Details will be shown in the presentation.