Section II. On-line separator systems and target techniques
Recent development of high-temperature metal targets for ISOLDE

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Abstract

The improved target and ion-source system to be used at the SC-ISOLDE on-line mass separators is presented. Tests of a number of refractory metals with respect to their use as target materials are described. The materials discussed are pure metals and mixtures of graphite and platinum-like metals. Rapid release of a number of nuclear reaction products from powders and foils of titatium and thorium is shown. The release properties of rhenium and iridium are described. The enhanced release of refractory elements obtained from these metals by means of reaction with CF4 are related to the importance of in-grain diffusion versus surface desorption. The difference in performance between powder and foil targets is discussed. On-line tests of some of these materials combined with new high-temperature plasma-discharge type ion sources are described and the potential use of yet untested systems is discussed.

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