Patent Number: 
Section: claims

1. A method for producing ground state 229Th, comprising the steps of:providing a target material comprising 226Ra,bombarding said target material with helium nuclei from a helium nuclei source to form ground state 229Th, andcontrolling said helium nuclei source to produce said helium nuclei with an incident energy between 8 and 20 MeV. 2. The method of claim 1, wherein said helium nuclei comprise alpha particles. 3. The method of claim 1, wherein said helium nuclei comprise alpha particles and said helium nuclei source is controlled to produce alpha particles having an incident energy between 15 MeV and 20 MeV. 4. The method of claim 1, wherein said helium nuclei comprise alpha particles and said helium nuclei source is controlled to produce alpha particles having an incident energy selected to preferentially trigger a 226Ra[α,n]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 5. The method of claim 1, wherein said helium nuclei comprise helium-3 particles. 6. The method of claim 1, wherein said helium nuclei comprise helium-3 particles and said helium nuclei source is controlled to produce helium-3 particles having an incident energy selected to preferentially trigger a 226Ra[3He,γ]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 7. A method for producing ground state 229Th, comprising the steps of:providing a target material comprising 226Ra,bombarding said target material with helium nuclei from a cyclotron nuclei source to form ground state 229Th, andcontrolling said cyclotron to produce said helium nuclei with an incident energy between 8 and 20 MeV. 8. The method of claim 7, wherein said helium nuclei comprise alpha particles. 9. The method of claim 7, wherein said helium nuclei comprise alpha particles and said cyclotron is controlled to produce alpha particles having an incident energy between 15 MeV and 20 MeV. 10. The method of claim 7, wherein said helium nuclei comprise alpha particles and said cyclotron is controlled to produce alpha particles having an incident energy selected to preferentially trigger a 226Ra[α,n]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 11. The method of claim 7, wherein said helium nuclei comprise helium-3 particles. 12. The method of claim 7, wherein said helium nuclei comprise helium-3 particles and said cyclotron is controlled to produce helium-3 particles having an incident energy selected to preferentially trigger a 226Ra[3He,γ]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 13. A method for producing ground state 229Th, comprising the steps of:providing a target material comprising 226Ra,bombarding said target material with alpha particles from an alpha particle source to form ground state 229Th, andcontrolling said alpha particle source to produce said alpha particles with an incident energy between 15 and 20 MeV. 14. The method of claim 1, wherein said alpha particle source is controlled to produce alpha particles having an incident energy selected to preferentially trigger a 226Ra[α,n]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th.