Physics

A series of experiments on the fission of superheavy nuclei formed in reactions with 58Fe ions, namely, the 58Fe+208Pb, 58Fe+232Th, 58Fe+244Pu and 58Fe+248Cm reactions, were carried out during the past two years at the Flerov Laboratory of Nuclear Reactions (JINR, Dubna) using the CORSET+DEMON setup. Experimental data were obtained on the mass and energy distributions of fission fragments of compound

... Giardina, Y. Aritomo, AA Bogatchev, MG Itkis, JM Itkis, J. Kliman, GN Kniajeva, NA Kondratiev, EM Kozulin, L. Krupa, Yu. ... Academy of Sciences; • Nuclear Physics Board of the European Physical Society; • Scientific Council of the GANIL Laboratory, France; • Advisory Committee ...

The experimental data on the capture and evaporation residue cross-sections obtained in the 48 Ca +208 Pb reaction were analyzed in the framework of the dynamical model based on the dinuclear system concept and advanced statistical method to clarify the reaction mechanism. The experimental excitation function of the capture reactions was decomposed into contributions of the fusion–fission, quasifission and fast-fission processes. Total evaporation residues and ones after neutron emission were only calculated and compared with the available experimental data.

The decrease of the evaporation residue yields in reactions with massive nuclei is explained by an increase of the competition between quasifission and complete fusion processes and by the decrease of the survival probability of the heated and rotating nuclei against fission along the de-excitation cascade of the compound nucleus. The experimental data on the yields of evaporation residue, fusion-fission and quasifission fragments in the 48 Ca + 154 Sm reaction are analyzed in the framework of the combined theoretical method based on the dinuclear system concept and advanced statistical model. The measured yields of evaporation residues of the 48 Ca + 154 Sm reaction have been well reproduced and yields of fission fragments were analyzed using the partial fusion and quasifission cross sections calculated in the dinuclear system model. Such a way of calculation is used to find optimal conditions for the synthesis of the new element Z = 120 (A = 302) by studying the excitation functio...

Three novel experiments in spontaneous and thermal neutron induced fission all with a bearing on angular momentum in fission are reviewed. In the first experiment it was observed that, in the reaction 235U(n, f) with incident polarized cold neutrons, the nucleus undergoing scission is rotating. This was inferred from the shift in angular distributions of ternary particles being dependent on

To describe the solvation properties of polar or charged species, and the reaction free-energy of charge transfers, we propose a generalization of the Marcus electrostatic polarization free-energy functional which accounts for the molecular nature of the solvent. ...