Ion guide method for on-line isotope separation

A new ISOL technique, the ion guide method for isotope separation, has been developed. The method is based on thermalization of primary recoil ions from nuclear reactions in helium and on their transfer by helium flow through a differential pumping system into the accelerating stage of an isotope separator. With this approach, separation times in the submillisecond region are achievable for all elements. The ion guide has no ionizer but instead exploits charge exchange mechanisms related to nuclear reactions and recoil thermalization processes. Operation takes place at room temperature and the simple construction involves no components that can wear out. These properties ensure smooth and stable operating conditions. The overall separation efficiencies measured for heavy nuclides produced by light-ion reactions are up to 10%. The shortest-lived activity identified in an on-line separation is the 182-μs isomeric state of 207Bi. The production rate of the mass separated 440-μs isomeric state of 43Sc is ≅ 2x103 ions/μC. (orig.)