title: The production of radionuclides for nuclear medicine from a compact, low-energy accelerator system.
abstract: BACKGROUND
  The field of nuclear medicine is reliant on radionuclides for medical imaging procedures and radioimmunotherapy (RIT). The recent shut-downs of key radionuclide producers have highlighted the fragility of the current radionuclide supply network, however. To ensure that nuclear medicine can continue to grow, adding new diagnostic and therapy options to healthcare, novel and reliable production methods are required. Siemens are developing a low-energy, high-current - up to 10 MeV and 1 mA respectively - accelerator. The capability of this low-cost, compact system for radionuclide production, for use in nuclear medicine procedures, has been considered.
  
  
  METHODS
  The production of three medically important radionuclides - (89)Zr, (64)Cu, and (103)Pd - has been considered, via the (89)Y(p,n), (64)Ni(p,n) and (103)Rh(p,n) reactions, respectively. Theoretical cross-sections were generated using TALYS and compared to experimental data available from EXFOR. Stopping power values generated by SRIM have been used, with the TALYS-generated excitation functions, to calculate potential yields and isotopic purity in different irradiation regimes.
  
  
  RESULTS
  The TALYS excitation functions were found to have a good agreement with the experimental data available from the EXFOR database. It was found that both (89)Zr and (64)Cu could be produced with high isotopic purity (over 99%), with activity yields suitable for medical diagnostics and therapy, at a proton energy of 10MeV. At 10MeV, the irradiation of (103)Rh produced appreciable quantities of (102)Pd, reducing the isotopic purity. A reduction in beam energy to 9.5MeV increased the radioisotopic purity to 99% with only a small reduction in activity yield.
  
  
  CONCLUSIONS
  This work demonstrates that the low-energy, compact accelerator system under development by Siemens would be capable of providing sufficient quantities of (89)Zr, (64)Cu, and (103)Pd for use in medical diagnostics and therapy. It is suggested that the system could be used to produce many other isotopes currently useful to nuclear medicine.
authors.affiliation: Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, United Kingdom. Electronic address: wdw24@cam.ac.uk.
authors.forename: William D
authors.initials: WD
authors.lastname: Webster
authors.affiliation: Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, United Kingdom.
authors.forename: Geoffrey T
authors.initials: GT
authors.lastname: Parks
authors.affiliation: Siemens Ltd, Corporate Technology, Moscow.
authors.forename: Dmitry
authors.initials: D
authors.lastname: Titov
authors.affiliation: Siemens CT TIP Technology and Concepts, Oxford.
authors.forename: Paul
authors.initials: P
authors.lastname: Beasley
mesh_terms: D009683:Nuclear Medicine; D010315:Particle Accelerators; D011854:Radiochemistry / Q000295:instrumentation*; D011868:Radioisotopes / Q000737:chemistry*
chemical_list: D011868:Radioisotopes
keywords: (103)Pd; (64)Cu; (89)Zr; Accelerator production; Low-energy