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Abstract: The feasibility of in-beam polarization of nuclear spin in F+ beams was studied. It was demonstrated that metastable atomic fluorine could be optically pumped on the closed transition (3s 4P5/2→3p 4D7/2) at 686nm. The metastable production efficiency in sodium vapor was measured using optical depopulation pumping of the metastable on the (3s 4P5/2→3p 4D5/2) transition at 678nm. At low helium density, 0.24 (+0.16/−0.03) of the reionized beam was derived from metastables, implying an ion beam polarization of 24% would be feasible if the metastables were fully polarized. The hyperfine structures of the 3s 4P5/2, 3p 4D5/2 and 3p 4D7/2 states in 19F were measured via laser-induced fluorescence and modulated optical depopulation pumping. Based on these results, a scheme is suggested for polarizing 20F. [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]

Abstract: A compact -ray detecting nuclear magnetic/quadrupole resonance system with a permanent magnet was developed at ISAC/TRIUMF to measure ground-state electromagnetic moments of short-lived nuclei. Polarized Na beams produced using the collinear optical-pumping technique were used to demonstrate the properties of the system. The degree of nuclear polarization and the spin–lattice relaxation times of the 20,21,26,27,28Na isotopes in NaF, TiO2, LiNbO3, MgF2, ZnO, Pt, and Mg single crystals at room temperature are reported. The electric-quadrupole coupling constants of 20,21Na in TiO2, ZnO and Mg, and that of 27Na in ZnO are also reported. The quadrupole moments of 20,21Na were extracted from the electric-quadrupole coupling constants in ZnO, using the known quadrupole moment of 27Na. [Copyright &y& Elsevier]

Abstract: The release fraction of implanted 12keV K (=1.23s) ions from a variety of catcher foils was measured. The temperature dependence was measured for V, Fe, Ni, Y, Zr, Nb, Mo, Hf, Ta, W, Re, C, and Pt foils. The release fraction was found empirically to be a reasonably universal function of the ratio of temperature to catcher melting point. Limits on diffusion parameters (ignoring desorption) and on desorption (ignoring diffusion) were deduced. The results were used to find the optimal neutralizing catcher foil to load a neutral atom trap, and can be used to help choose ISOL target production materials. [Copyright &y& Elsevier]

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]