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-³He 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 ¹¹C from the ¹⁴N(p, ) ¹¹C 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 MeV fusion protons is a thin metal foil (~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 ¹⁴N gas pressure was performed to optimize the efficiency of fusion protons in producing ¹¹C. The MCNPX 2.5.0 simulations predicted that an optimized system could produce 390 nCi of ¹¹C with the present laboratory scale IEC device at the University of Wisconsin, which has a D-³He fusion rate of 2 x 10⁷ protons per sec (p/s).