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[en] The unified global energy dependence of the induced fission times obtained by the experimental crystal blocking technique for nuclei with Z=91-94 in the range of initial excitation energy from 5 to 250 MeV was analyzed. It was demonstrated that for the energies up to 60-70 MeV the fission times can be described in the frame of the statistical theory taking into account the double-humped structure of the fission barrier and the lifetimes of both classes of excited nuclear states realized in the first and second potential wells. However, for the excitation energies above 70 MeV it is needed to consider the dynamical effects in fission channel
[en] I use a simple model to parameterize mirror energy differences for several nuclei with N=8 or 10 and their mirrors with Z=8 or 10. I then use the results of the fit to predict the energy of the ground state of the unbound nucleus 15Ne: E2p=2.68(24) MeV.
[en] The method is based on the Bethe level density expression, where the parameters are used with constraints. It is applied to the level density of compound resonances observed at neutron separation energy. The change of the pairing energy compared to the ground state value determined by mass differences is discussed for different mass regions. (Auth.)
[en] Pairing reduction in deformed nuclei due to the blocking effect is treated exactly with the particle-number-conserving method. Merely due to the blocking effect the gap parameter Δ becomes configuration-dependent. The pairing reduction delta(ν0) depends sensitively on the location of the blocked level ν0 relative to the Fermi surface, lambda, and decreases rapidly with vertical strokeepsilonν0lambdavertical stroke. The pairing reduction delta(ν0) depends also sensitively on the single-particle level distribution near the Fermi surface. In some special cases pairing reduction may be negative. With an increasing number of the blocked levels (above the Fermi surface) the gap parameter Δ decreases dramatically. If the blocked levels are below the Fermi surface the situation is quite different and as the number of the blocked levels becomes sufficiently large the pairing reduction may vanish. (orig.)
[en] Symmetry and pairing energies of atomic nuclei are related to the differences between the excitation energies of isobaric analog states in the same nucleus. Numerous such excitation energies are known experimentally. In addition, a comprehensive global set can be deduced from the available experimental masses by applying Coulomb energy corrections. Replacing the experimental mass data by available theoretical mass predictions as basis for this procedure to extract symmetry and pairing energies makes it possible to directly compare theoretical and experimental quantities. These comparisons reflect upon the goodness or possible shortcomings of the respective mass equation since symmetry energies are related to the curvature of the nuclear mass surface. A discussion of eleven selected mass equations or procedures for reproducing experimental masses and extrapolating into regions of unknown nuclei is presented
[en] The cross sections and the angular distributions of fragments emitted in heavy ion reactions are calculated on the basis of a diffusion mechanism associated with the mass (charge) asymmetry of a short-lived intermediate complex. The calculated quantities are compared with experimental results. (Auth.)
[en] Penetrability through a three-humped barrier has been calculated in quasi-classical approximation and a plausible explanation of sub-barrier fission characteristics of thorium is suggested. (Auth.)
[en] In this work, we have systemically investigated the ground-state properties of the rare-earth even-even nuclei with the parameter set FSUGold that includes the isoscalar-isovector coupling to soften the symmetry energy. It is the first time that this parameter set is applied to investigate the properties of deformed nuclei. The present study is mainly focused on the nuclei with the known experimental binding energies ranging from Z=58 to Z=70. The calculated binding energies, quadrupole deformations, and charge radii are in good agreement with the available experimental data. It has been shown that the parameter set FSUGold is as successful as the NL3 in reproducing the known ground-state properties of deformed nuclei.