Properties Of Superheavy Elements Research Articles

Concept of a new Universal High-Density Gas Stopping Cell Setup for study of gas-phase chemistry and nuclear properties of Super Heavy Elements (UniCell)

Abstract Here we propose a concept of a new universal high-density gas stopping cell setup (UniCell), whose advantages are based on use of the ultra-compact RF ion-funnel technique. It will allow for the fast ( ∼ 2 ms) and highly efficient (up to 100%) extraction of ions in a wide range of masses from high-density gas stopping cells and, in particular, ions of superheavy elements (SHE) for gas-phase chemical studies and nuclear property (high-precision mass spectrometry, laser and decay spectroscopy) measurements. The gas cell consists of a traditional DC-cage and (RF+DC)-funnel of a novel compact design. For physical researches, the UniCell is equipped with the additional system of three RF-funnels placed on the axis downstream the gas cell exit, which will allow for a high-efficient and fast extraction of ions into high-vacuum with production of continuous and pulsed ion beams having a record small transverse and longitudinal emittance. For the gas-phase chemistry studies, the system of three extraction RF-funnels can be replaced by a gas chromatography detector array with an original gas ejector-interface, which will allow, when it will be necessary for ions neutralization, to add different reactive gases into the helium flow. The operation regimes of the proposed UniCell have been explored by detailed gas dynamic and Monte Carlo ion-trajectory simulations, whose results are presented and discussed.

Nuclear Properties of Super Heavy Elements (Theory)—Island of Stability of Superheavy Nuclei—

Nuclear Properties of Super Heavy Elements (Theory)—Island of Stability of Superheavy Nuclei—

Simulation of chemical properties of superheavy elements from the island of stability

The review covers main methods of the first-principle based electronic structure simulation used for the prediction of the properties of superheavy element atoms and compounds. The areas of applicability of these methods and the principal and practical limitations of their accuracy are analyzed. The regularities in the changes of the chemical properties on going from superheavy elements to their closest homologs are discussed.

Synthesis and Properties of Superheavy Elements

This paper, presented at a RAS Presidium meeting, deals with the synthesis of relatively long-lived superheavy elements with atomic numbers 114 to 118. It was carried out at the Joint Institute for Nuclear Research by Academician Yu.Ts. Oganesyan’s research team. The focus was on the discovery of a new region of stability of superheavy elements.

Detecting system of the setup for studying chemical properties of superheavy elements using the gas chemistry techniques

A setup for studying the physicochemical properties of superheavy elements in experiments involving gas transport systems is described. The setup is composed of four detecting modules with semiconductor detectors; systems of data acquisition, storage, and processing; a cooling system for semiconductor detectors; and a vacuum system. In each detecting module, there are two oppositely located four-strip semiconductor detectors. The detecting system is capable of detecting with a high efficiency α particles and spontaneous fission fragments produced in decays of superheavy elements.

Self-consistent mean-field description of nuclear structure and dynamics—a status report

This contribution deals with the predictive power of the Skyrme-Hartree-Fock model. First, we discuss the phenomenological adjustment of the Skyrme energy-functional and the choice of proper fit data. Then, we check the reliability in extrapolations to other observables and nuclei, using two strategies: first, comparison with data for observables not included in the fit, and second, an estimate of the extrapolation error by virtue of the least-squares fitting techniques. Test cases will be energies of extremely neutron rich Sn isotopes as well as energies, giant resonances, and fission properties of super-heavy elements.

Ground-state properties of superheavy elements in macroscopic-microscopic models

Masses, α-decay and spontaneous fission half-lives of superheavy elements are studied in macroscopic-microscopic approaches with two different macroscopic models and the delta-pairing interaction. Model mass deviations obtained with different formulae are 0.5-0.8MeV.

Synthesis and Properties of Superheavy Elements

Synthesis and Properties of Superheavy Elements

Relative Volatility of (Oxy)chlorides of Light, Heavy, and Superheavy Transition Metals of Groups IV-VI

Analysis of the gas-chromatographic and thermochromatographic behavior of transition metal (oxy)chlorides shows that the compounds of elements 104-106 are more volatile than those of their lighter homologs. The ionic radii of elements 104-106 are also smaller than those of the lighter homologs. These facts are due to the influence of the relativistic effect on the properties of superheavy elements.

Synthesis and Properties of Superheavy Elements

Synthesis and Properties of Superheavy Elements

Empirical analysis of the formula for the binding energy of nuclei

An accurate knowledge of the properties of the nuclear energy surface is important not only for practical reasons (to calculate nuclear masses, and to predict the properties of superheavy elements and nuclei far from the/3-stability line), but also to check and refine nuclear models. The well-known semiempirical formula for the binding energy due to Bethe and Weizsacker [1] has been subjected to a number of refinements and modifications in order to obtain better agreement with experiment [2-10]. The correction terms, introduced from theoretical considerations, fake into account the specific features of the distribution of nucleons in the nucleus (the diffuseness of the boundary, the nonuniformity of the distribution in the inner region, and the difference between the neutron and proton densities) [2-5], the effects of deformation and compressibility of the nuclei [6-10], Coulomb exchange interaction [3, 61, etc. However, because there is no rigorous theory of the nucleus the role of the various correction terms remain unclear. As far as their empirical basis is concerned, the introduction of correction terms into the equation for the binding energy, despite the addition of new parameters, does not lead to any appreciable improvement in the agreement with experiment. Nevertheless, the introduction of purely empirical corrections to the parity and the effects of the shells considerably improves the agreement with experiment [1, 3, 6, 11]. All this stimulated us to try to clarify the features of the structure of the formula for the binding energy, without previous resource to any model representations, and based exclusively on experimental data. It is well lmown that for any fixed mass number A the stability of the isobars falls, while the energy increases the further the nuclei are from the region of stability both on the neutron-excess side and on the proton-excess side. A detailed analysis of the experimental data given in [12-15], shows that within the limits of experimental error the isobar cross sections of the energy surface in the regions between the magic numbers of neutrons and protons are (for nuclei of each of the four types of parity) quadratic parabolas, so that the total energy of a nucleus with mass number A and charge Z can be represented in the form [12-14]