Production of At for alpha radiotherapy via Bi(Li,5n)Rn

Nishinaka, Ichiro; Washiyama, Koshin*; Yokoyama, Akihiko*; Maeda, Eita*; Hashimoto, Kazuyuki; Makii, Hiroyuki

no journal, , 

A Rn/At generator has been proposed to supply a radiotracer At with a half-life (T = 7.2 h) for medical applications. To establish a technology of the Rn/At generator, Rn (T = 14.7 h) has to be produced through the Bi(Li, 5n)Rn reaction without melting bismuth metal targets due to heat produced by the irradiation of 60 MeV Li ion beams. In this work, we have studied the effects of a He gas cooling system of an irradiation chamber constructed for the production of Rn. Irradiations were carried out at the JAEA tandem accelerator using the irradiation chamber equipped with the He gas cooling system. The results show that the He gas effectively cools the targets and the cooling efficiency is nearly independent of the pressure ( 1 kPa) and the flow rate (20 L/min) of the He gas.