Generation of angular momentum of fission fragments in a cluster model

Based on the dinuclear system concept, the role of bending vibrations in creation of the angular momentum of primary fission fragments is investigated. For ²⁵²Cf spontaneous fission, the angular momenta of the fragments are calculated as a function of the neutron multiplicity and compared with available experimental data. Different cluster compositions of the ²⁵²Cf fission modes at the scission point are considered.     

Dielectronic Recombination of Very Heavy Lithiumlike Ions

Hyperfine Interactions - An overview of measurements of dielectronic recombination (DR) with the heaviest lithiumlike ions is presented. The experiments have been carried out at the heavy ion...     

Dynamics of capture and fusion in heavy ion collisions

The effect of entrance channel on decrease of the complete fusion cross sections and on the yield of reaction products are associated with the quasifission which depends on the mass asymmetry and shell structure of colliding nuclei. In reactions of massive projectile and target nuclei, the competition between complete fusion and quasifission appears at the stage of compound nucleus formation, in addition to the increase of the fission probability. It is shown that the yield of quasifission products may be symmetric or asymmetric in dependence on peculiarities of shell structure of reaction fragments. Marima of mass or charge distributions are connected with the peculiarities of shell structure of reaction fragments.     

Verdunstungsverluste aus der Preglschen Präzisionswägepipette über Phosphorpentoxyd

Zusammenfassung Präzisionswägepipetten nachPregl mit einem Inhalt von 1 ml eignen sich auch dann für die Dichtebestimmung von biologischen Flüssigkeiten, wenn man aus Gründen der Versuchsanordnung gezwungen ist, die gefüllten Pipetten vor der Wägung längere Zeit in einem Exsikkator über Phosphorpentoxyd aufzubewahren. Die eintretenden, zeitabhängigen Gewichtsverluste durch Verdunstung bleiben innerhalb der üblichen Fehlergrenzen.

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Summary Precision weighing pipettes (afterPregl) with a capacity of 1 ml are suitable for determining the density of biological fluids, in case the experimental conditions require the storing of the filled pipettes for a considerable period, before weighing, in a desiccator over phosphorus pentoxide. The loss of weight due to evaporation is dependent on the waiting period but it remains within the usual limits of error.

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Résumé Les pipettes de précision dePregl de 1 ml conviennent aussi pour la mesure de la densité de liquides biologiques quand on les maintient pleines avant la pesée un certain temps dans un dessiccateur sur l'anhydride phosphorique, lorsque l'ordre des expériences est déterminé. Les pertes de poids qui se produisent au cours du temps par évaporation restent au-dessous des limites habituelles d'erreur.

     

Description of alternating-parity bands within the dinuclear-system model

A cluster approach is used to describe ground-state-based alternating-parity bands in even–even nuclei and to study the band-termination mechanism. A method is proposed for testing the cluster nature of alternating-parity bands.     

Synthesis of superheavy elements and the process of complete fusion of massive nuclei

The development of various approaches to describing the complete fusion of nuclei and their connections with experimental studies is discussed. A brief account of the dinuclear-system concept (DNSC), the approach proposed at Dubna, is given. The DNSC revealed two important features of the complete fusion of massive nuclei: the existence of the inner fusion barrier B _fus ^* and the competition between complete fusion and quasifission channels in a dinuclear system formed at the capture stage. The DNSC was applied to the analysis of reactions used to synthesize superheavy elements (SHE). The DNSC provided a basis for the models of competition between complete-fusion and quasifission channels. Using these models, one can describe the cross section for SHE production in cold-and warm-fusion reactions.