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Lifetime measurements of excited states in 149Nd have been performed using the advanced time-delayed $ \beta$ $ \gamma$ $ \gamma$( t) method. Half-lives of 14 excited states in 149Nd have been determined for the first time or measured with higher precision. Twelve new $ \gamma$ -lines and 5 new levels have been introduced into the decay scheme of 149Pr based on results of the $ \gamma$ $ \gamma$ coincidence measurements. Reduced transition probabilities have been determined for 40 $ \gamma$ -transitions in 149Nd . Configuration assignments for 6 rotational bands in 149Nd are proposed. Enhanced E1 transitions indicate that the ground-state band and the band built on the 332.9keV level constitute a pair of the $\ensuremath K^{\pi} = 5/2^{\pm}$ parity doublet bands. Potential energy surfaces on the $\ensuremath (\beta_{2},\beta_{3})$ -plane have been calculated for the lowest single quasi-particle configurations in 149Nd using the Strutinski method and the axially deformed Woods-Saxon potential. The predicted occurrence of the octupole-deformed K = 5/2 configuration is in agreement with experiment. Unexpectedly low $\ensuremath \vert D_0\vert$ values obtained for the $\ensuremath K^{\pi} = 5/2^{\pm}$ parity doublet bands may result from cancellation between the proton and neutron shell correction contributions to $\ensuremath \vert D_0\vert$ . [ABSTRACT FROM AUTHOR]

Detailed theoretical calculations of the properties of the neutron-excess odd-odd nucleus 134Sb are performed by using different theoretical approaches. A comprehensive comparison with the recent experimental data is performed; this comparison suggests the presence of isomeric states among the low-lying levels of this nucleus. These states are the twins of the corresponding levels of the odd-odd nucleus 210Bi that is situated near the stability line. The obtained results manifest the similarity of nuclear structure in the region of the “remote” doubly magic nucleus 132Sn and in the region of the classical stable doubly magic nucleus 208Pb. [ABSTRACT FROM AUTHOR]

A combined target-ion source unit (ionizing target) has been developed for the on-line production of radioactive single-charged ions. The target is able to withstand temperatures of up to 2500 °C and also acts as an ion source of surface, electron-beam, and laser ionizations. Using tantalum foil as a target material, the on-line combined target-ion source unit efficiency, which is the product of the ionization and release efficiencies, has been obtained for neutron-deficient isotopes of Eu, Gd, and Yb. These nuclides were ionized by the surface ionization inside a hot tungsten target container, holding tantalum foils as a target material. The results of the combined target-ion source unit use for on-line laser resonant ionization spectroscopy investigation of neutron-deficient Gd isotopes have been also presented. For neutron-rich isotopes produced from a high-density UC target, which were ionized by the surface ionization inside the target container, the ionization efficiency values have been obtained close to 100% for Rb and Cs and 10% for In. For Ag and Sn neutron-richisotopes, the values of the electron-beam ionization efficiency in the volume of the targetcontainer, correspondingly equal to 4% and 2%, have been obtained. [ABSTRACT FROM AUTHOR]

The mass surface of nuclei close to the doubly magic nuclide [sup 78]Ni is calculated by two methods. The first relies on the multiparticle shell model based on an effective interaction and a mean nuclear potential. The second employs the concept of so-called "magic crosses" and enables us to determine the masses of odd-odd nuclei close to [sup 78]Ni by using similarity of the shell structure and neutron-proton interaction in the region of nuclei under consideration and in the region of heavy magic nuclides. The energies of the separation of one and two neutrons from nuclei close to [sup 78]Ni and the energies of the β decay of these nuclei—recall that these quantities of astrophysical interest—are presented. [ABSTRACT FROM AUTHOR]

Previously unobserved nuclei ofSm (T=42+4 s) andDy(t=18+3 s) have been identified using an on-line mass separating facility, operating on a 1 GeV proton beam /1/. [ABSTRACT FROM AUTHOR]