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Abstract: Techniques have been developed for on-line collection and transfer to a measurement cell of rare noble gas isotopes. A low-energy isotope separator beam is stopped in a foil. After collection, the foil is heated, and the noble gas atoms are cryopumped to a cold finger and then transferred with a buffer gas to a measurement cell. This has been tested with 120Xe produced from a 120Cs beam at the TRIUMF ISAC facility, and greater than 40% efficiency for transfer from the foil to the cell has been demonstrated. The technique will be used for electric dipole moment measurements with radon isotopes and may also be useful for other measurements with gaseous targets including laser spectroscopy. [Copyright &y& Elsevier]

Abstract: The diffusion-limited release of radioactive 120Xe from several thin metal foils abruptly heated to temperatures of order 1000°C while in a vacuum is characterized and interpreted in terms of impurity atom diffusion coefficients. The 120Xe impurities were produced in situ from the decay of 120Cs implanted into Ta, Pt, and Zr foils from a 30keV mass-separated ion beam. The temperature dependence of the diffusion coefficients extracted from our data is well described by Arrhenius relations, for which best-fit parameters are presented. The fastest release of 120Xe for a given set of implantation conditions and temperature is observed for Zr, although its reactivity may prove problematic for its use as a catcher foil. A number of convenient analytic formulae for the diffusion-limited release of impurity atoms are presented. [Copyright &y& Elsevier]