Patent Number: 
Section: claims

1. An Actinium-225 generator, comprising:a neutron source;a neutron target arranged to receive neutrons emitted from the neutron source, wherein the neutron target comprises nickel, manganese, or iron; anda proton target arranged to receive protons emitted from the neutron target, wherein the proton target comprises radium-226. 2. The Actinium-225 generator of claim 1, wherein the neutron target and the proton target are concentric cylinders surrounding the neutron source. 3. The Actinium-225 generator of claim 1, wherein the neutron source has a source activity of at least 1E15 Bq. 4. The Actinium-225 generator of claim 1, wherein the neutron source has a source activity of at least 14 MeV. 5. The Actinium-225 generator of claim 1, wherein the neutron source is Californium-252. 6. The Actinium-225 generator of claim 1, wherein the neutron target comprises nickel and has a thickness of 0.01-0.06 mm. 7. The Actinium-225 generator of claim 1, wherein the proton target comprises RaCl2 and has a thickness of 4.5-5.5 mm. 8. A method of producing Actinium-225, comprising:bombarding a neutron target with neutrons from a neutron source to produce a proton beam, wherein the neutron target comprises nickel, manganese, or iron; andbombarding a proton target with the proton beam, wherein the proton target comprises radium-226. 9. The method of claim 8, wherein the neutron target and the proton target are concentric cylinders surrounding the neutron source. 10. The method of claim 8, wherein a proton energy of the proton beam is 10 MeV or higher. 11. The method of claim 8, wherein the neutron source has a source activity of at least 1E15 Bq. 12. The method of claim 8, wherein the neutron source has a source activity of at least 14 MeV. 13. The method of claim 8, wherein the neutron source is Californium-252. 14. The method of claim 8, wherein the neutron target comprises nickel and has a thickness of 0.01-0.06 mm. 15. The method of claim 8, wherein the proton target comprises RaCl2 and has a thickness of 4.5-5.5 mm.