An H₂¹⁸O water target for the production of ¹⁸F-fluoride in the TR-13 cyclotron

This thesis presents the design, operation, performance and heat transfer modeling of a ¹⁸F production target for the EBCO/TRIUMF TR-13 cyclotron. This target employs the ¹⁸O(p,n) ¹⁸F reaction in ¹⁸0-enriched water. Positron emission tomography (PET) depends upon the availability of short-lived positron-emitting radionuclides, such as, ¹¹C, ¹³N, ¹⁵O, for radiopharmaceutical syntheses. Among the most important of these radionuclides is ¹⁸F (t1/2=109.6 min). It is almost exclusively produced in small medical cyclotrons by proton bombardment of isotopically enriched ¹⁸O-water in small volume targets. Production targets are required that can produce large quantities reliably, efficiently and economically. A key design component in such targets is the dissipation of heat generated as the proton beam is stopped within the target material. In order to better understand the heat transfer mechanisms involved and their relation to production target design, an ¹⁸F production target was constructed and a heat transfer model based on measurements was developed. The results derived from the model were in good agreement with the data from the irradiation experiments, in particular in the higher current regions that are required for high yield ¹⁸F production. It is believed that the target discussed here can be successfully used in the routine production of ¹⁸F in sufficient quantities and of adequate quality for in vivo applications.Science, Faculty ofPhysics and Astronomy, Department ofGraduat