مجله علوم و فنون هستهای (Feb 2017)
Investigation of 18F and 13N Radioisotopes Production Using Cyclotron Recirculating Liquid Target
Abstract
Two radioisotopes of 18F (T1/2=109.7 min, Iβ+= 97%, Eβ+= 0.63 MeV), and 13N (T1/2=10min, Iβ+=100%, Eβ+=0.96 MeV) decay almost completely via positron emission. Due to this characteristic, these radioisotopes are used in PET (positron emission tomography) camera for detection of cancer cells. In this article, after calculating the excitation function for nuclear reactions leading to the 18F, 18O (p, n) 18F, and 13N, 16O (p, α) 13N formation using the ALICE-91 nuclear code and by a comparison of the results with the experimental data, the best range of energy to produce with a cyclotron accelerator and the amount of heat deposited to the target material, was determined. For the waste heat removal, a miniature heat exchanger was designed and manufactured. A thermal design of the heat exchanger by the Aspen HTFS+ software was created, and its mechanical plan sheet was drawn using the SolidWorks software. After the fabrication of the heat exchanger and recirculation liquid target located at the liquid target room, 13N was produced via pure water proton bombardment with 17.5 MeV energies verifying the theoretical calculations.
