No abstract available

[en] Trends of 2⁺ and 0⁺ states in Yb nuclei and measured B(E2; 0⁺ yields 2⁺) values are reported

No abstract available

[en] A microscopic analysis of moments of inertia is performed within the cranked Nilsson model. Special emphasis is put on the second-derivative moment of inertia, Jsup((2)). Contributions to this from changes of rotational frequency and deformation are separately discussed. A simple expression for the latter is derived and it is for a studied series of Yb isotopes usually found to contribute with less than 10% to the total Jsup((2)) value. Jsup((1)), Jsup((2)) and Jsub(rigid) are calculated as functions of spin at the appropriate equilibrium deformations for the even-even nuclei sup(160-176)Yb. Variations of Jsup((2)) with particle number and spin are discussed. Relations between Jsup((2)) and the deformation are studied in detail, especially in connection with the super-backbending. (orig.)

[en] Formulae are presented for the construction of ''double'' routhians from which both the configuration- and ''gauge''-space collective energies have been removed. Such values are constructed for a series of ytterbium isotopes varying in mass from 159 to 170 and are presented as a function of lambdasub(n) for constant (h/2π)ω, and as a function of (h/2π)ω for constant lambdasub(n). This analysis indicates the presence of sizable correlations for the lowest (π,α)=(+,0) configuration (and to a lesser extent for the lowest (+,1/2) configuration) at the largest rotational frequencies for which such an analysis can be accomplished. An empirical spectrum of single-neutron states is constructed from values of lambdasub(n) and is compared both to a similar spectrum of states constructed from excitation energy differences and to cranking-model calculations. (orig.)

[en] The isotopic composition of ytterbium in meteoritic and terrestrial materials was measured using a solid source mass spectrometer. Isotopic abundances of meteoritic and terrestrial Yb agree within experimental errors. The relative isotope abundances for reagent Yb are 0.00429, 0.0964, 0.4512, 0.6887, 0.5075 and 0.3997 for the ¹⁶⁸Yb, ¹⁷⁰Yb, ¹⁷¹Yb, ¹⁷²Yb, ¹⁷³Yb and ¹⁷⁶Yb relative to ¹⁷⁴Yb respectively. Apart from linear mass fractionation, these data are in agreement with other published data. The concentration of Yb in 21 stony meteorites was determined using the isotope dilution method. In general, the agreement between this work and other published data is excellent. (author)

No abstract available

[en] Results are presented of the work on the development of a method for detecting ultra rare isotopes, based on the collinear isotope-selective laser ionization of atoms in a fast beam. The rare isotope ³He was detected at a selectivity of 10⁹ and isotope-selective ionization of krypton atoms was demonstrated. A scheme is suggested for detecting the rare radioactive isotopes ⁸⁵Kr and ⁸¹Kr. The technique has been exploited for the measurement of hyperfine structures and isotope shifts of unstable Yb isotopes. (orig.)

[en] We report on the progress in development of a highly accurate optical frequency standard based on the single ion of ytterbium-171 at the Institute of Laser Physics, Novosibirsk. (paper)

No abstract available