Production of radioactive beams of francium
Abstract
We describe the production of francium beams from the fusion-evaporation reaction Au197(O18,kn)Fr generated by a ∼100 MeV O6+18 beam on a thick gold target. The physics of the production process is discussed, together with estimates of expected production rates. The production target is heated to ∼1200 K and kept at a potential of +3 kV to enhance Fr diffusion and surface desorption, and to accelerate surface-ionized ions. Details are given on its design and construction. The performance of the target is measured as a function of primary beam energy and flux, target temperature and extraction voltage. Average production rates are 0.7×106 ions/s for 210Fr with a primary beam flux of 1012 particles/s, with peaks of 2×106 ions/s. From these measurements, information on the efficiency of the release processes is inferred.
- Publication:
-
Nuclear Instruments and Methods in Physics Research A
- Pub Date:
- February 2006
- DOI:
- 10.1016/j.nima.2005.11.193
- Bibcode:
- 2006NIMPA.557..390S