Cyclotron target designs

The medical cyclotron is a device which is used for the acceleration of charged particle. These charged particles are bombarded on the suitable target materials to produce medically useful radioisotopes via induced nuclear reaction. Target material is mounted on the target assembly which is attached to the cyclotron internally or externally. The target assembly design is concerned with loading the target material in to the beam path, keeping it there for effective irradiation and its quick removal after irradiation. It consists material selection and calculation of heat load, cooling, beam energy attenuation and production yield. For optimum production of radioisotope target assembly must be designed and fabricated carefully. Target design is specific to the cyclotron design. The medical cyclotron PETtrace-800 at RMC, BARC is an unshielded cyclotron capable of producing a proton beam of fixed energy 16.5 MeV. The facility has only liquid and gas target assemblies, which enables production of ¹³N, ¹⁵O, ¹¹C and ¹⁸F. However, towards increasing the utility of the existing facility (PETtrace-800) for the production of other relevant medical radioisotopes, a solid target assembly has been indigenously developed. The development of solid target assembly is a demanding task and involves considerable scientific and engineering challenges. This constitutes various tasks in order to achieve compatibility with the existing system, while ensuring radiation safety, proper target cooling during irradiation, transfer of the irradiated target disk to the hot cell and testing the suitability of the assembly for the intended application. The practical feasibility of the production of ¹¹¹In, ⁶⁴Cu and ⁸⁹Zr have been demonstrated first time at RMC, BARC using this solid target assembly