Optimizing irradiation parameters of cyclotron-produced radionuclides Cu-64, I-123 and I-124

Successful production of cyclotron-based radionuclides depends on various irradiation parameters including the type, energy and beam current of incident particle, target thickness and geometry as well as irradiation time. This paper presents theoretical ca(culations for optimization of future Cu-64, I-123 and I-124 radionuclide production using BATAN's CS-30 cyclotron from 64Ni(p,n))64Cu,123Te(p,n)123I, 124Te(p,n)124I and 124Te(p,2n)123I nuclear reactions. Optimum target thickness and proton incidence angle, proton energy and beam current which result in optimum End Of Bombardment (EOB) yields are highlighted. A well-developed and widely available software called Stopping and Range of Ion in Matter (SRIM) version 2013 are employed to determine the optimum Ni and Te target thickness for several irradiation requirements and then followed by calculations of the EOB yields. In addition, the calculated EOB yields are then compared with previous experimental results obtained elsewhere. For production of Cu-64, the optimum Ni target thickness when a 26.5 Me V proton beam is incident at 0o angle relative to the target normal should be nearly 1.5 mm which yields up to 560 mCi/uA. Hr at the end of the bombardment. At proton beam energy of 12 MeV, 12 MeV and 22 MeV for production of I-123 from Te-123 target, I~124 and I-123 from Te-124 targets respectively, the associated optimum target thickness are 0.64 mm, 0.65 mm and 1.8 mm whereas their EOB yields are predicted to be 30.6 mCilJ.1A.hr,4.2 mCilJ.1A.hrand 159.3 mCilJ.1A.hrrespectively. For all Cu-64, I-123 and 1-124 radionuclide production, comparisons with some selected experimental data indicate that the much-lower-than-expected EOB yields are mainly due to incorrect target thickness prepared for the irradiation.