[en] Spontaneous fission (T_sf) and alpha-decay half-lives (T_α) of the heaviest nuclei with atomic number 100 ≤ Z ≤ 114 are calculated on the basis of the deformed Woods-Saxon potential. The calculations of (T_sf) are performed by the WKB approximation, in the multi-dimensional dynamical-programing method (MDP). We have examined three different effects: the effect of higher even-multipolarity shape parameters (β₆ and β₈), the role of reflection-asymmetry (β₃ and β₅) and the influence of pairing degrees of freedom (Δ_p and Δ_n). Alpha-decay half-lives (T_α) have been calculated by the Viola-Seaborg (V-S) formula with the parameters modified to the latest experimental data

No abstract available

[en] Adapting the realistic single-particle Woods-Saxon potential the spontaneous half-lives of elements with Z>=104 are estimated. All even-even, odd-even and odd-odd nuclei are considered. In calculations of spontaneous fission half-lives phenomenological mass parameters are applied. The results allow to estimate hindrance factors for odd systems. As compared to calculations with Nilsson model and microscopic mass parameters, present results for spontaneous fission half-lives are 3-5 orders of magnitude higher in the case of heaviest nuclei (Z>=107). (author)

[en] Spontaneous fission half-lives of K-isomeric states are calculated on the basis of microscopic-macroscopic method. The isomeric state is assumed to be a 2-quasiparticle excited state with high angular momentum. The calculations were performed for nuclei with 96< Z<110 and 144< N<158. It was shown that in the case of K-isomeric states (if they exist) the spontaneous fission half-life time may be comparable to the spontaneous fission half-life time of the ground state. Therefore it was suggested that in measurements of fission half-lives it may be very important to distinguish between both possible components (or more) of the fission decay. (orig.)

[en] Short note. 2 refs

[en] In the unified temperature dependent nuclear model with Woos-Saxon single particle potential the adiabatic mass parameters and potential energies are calculated and discussed. Both liquid drop and shell correction are temperature dependent. Shell structure of mass parameter and fission barriers vanish for hot nuclear systems at T = 1.5 MeV. The mass parameter is shown to have irrotational behaviour at high temperature. (author)

[en] Adapting the realistic single-particle Woods-Saxon potential the half-lives of elements with Z ≥ 104 are estimated. Spontaneous fission, alpha decay and electron capture processes are treated. All even-even, odd-even and odd-odd nuclei are considered. In calculations of spontaneous fission half lives phenomenological mass parameters are applied. The results allow to estimate hindrance factors for odd systems. As compared to calculations with Nilsson model and microscopic mass parameters, present results for spontaneous fission half lives are 3-5 orders of magnitude higher in the case of heaviest nuclei (Z ≥ 107). (orig.)

[en] Published in summary form only

[en] A systematic study of spontaneous fission half-lives of superheavy nuclei in the framework of the macroscopic-microscopic method was performed. The macroscopic-microscopic calculations of the half-lives consist in determining the collective potential energy V which splits into microscopic and smooth average macroscopic parts as well as into a nucleus mass tensor of the nucleus undergoing the fission process. The microscopic part of the energy is calculated using the single-particle Woods-Saxon potential with a universal set of parameters. Two models of the residual pairing interaction were studied. In the first approach we used monopole pairing (with constant matrix elements G). In the second approximation the pairing matrix elements were calculated with ?-force and are state dependent. As the macroscopic part of collective energy we examined four different macroscopic models of nuclear energy: Myers - Swiatecki liquid drop, Droplet expansion, Yukawa-plus-Exponential and the Lublin-Strasbourg Drop model. The analysis covers a wide range of even-even superheavy nuclei from Z = 100 to Z = 126. The calculations of spontaneous fission half-lives were performed by means of a WKB approximation, in the multi-dimensional dynamical-programming method within parameters describe the shape of nuclei. The studies offer an opportunity of a comprehensive approach to a very interesting group of exotic heavier nuclei, which are currently investigated by experimenters

[en] Single particle nuclear levels are calculated on the basis of the potentials derived from the Extended Thomas-Fermi type Skyrme models for the Skyrme forces SkIII, SkM^* and SLy4. (author)