PRODUCTION OF CARBON-11 FROM D-3He FUSION DEVICES

Design, modeling and simulation work has been done to develop a system of producing radioisotopes by using D-He-3 fusion and the Inertial Electrostatic Confinement (IEC) fusion concept. This work provides a set of requirements for moving from the previous proof-of-concept experiments to medically relevant dosages of the radioisotopes used in Position Emission Tomography (PET). This study focuses primarily on the production of C-11 from the N-14(p, alpha)C-11 reaction, and could be extended to additional PET isotopes. A target was designed for gaseous parent materials; it consists of vacuum tight panels placed inside the vacuum vessel of an IEC device. The side facing the isotropic source of 14.7 Me V fusion protons is a thin metal foil (similar to 0.5 mm of Ti). The foil acts to separate the vacuum environment of the IEC device from the pressured gaseous environment of the target. Parametric analysis of the foil thickness and N-14 gas pressure was performed to optimize the efficiency of fusion protons in producing C-11. The MCNPX 2.5.0 simulations predicted that an optimized system could produce 390 nCi of C-11 with the present laboratory scale IEC device at the University of Wisconsin, which has a D-He-3 fusion rate of 2 x 10(7) protons per sec (p/s).