Study of electromagnetic properties of nuclei and structural changes at high spins in Yb isotopes

High-spin states of nuclei, populated by heavy-ion reactions, are of interest because they reveal changes in the structur of nuclei under stress. In the first part much of our insight into the structure of high-spin states is being provided by electromagnetic strength functions. In the second part, the level scheme of 158Yb has been extended to I = 37 by using the 98Mo (64Ni, 4n) reaction, and the backbending phenomena in Yb isotopes has been discussed. Untersuchungen der elektromagnetischen Eigenschaften an Kernen von Yb-Isotopen und ihren Strukturanderungen bei hohem Spin Durch Schwerionenreaktionen erhaltene Kernzustande mit hohen Spinwerten sind von Interesse, weil sie Anderungen der Kernstruktur unter Beanspruchung aufzeigen. Ein Grosteil unseres Verstandnisses der Struktur dieser Zustande grosen Spins resultiert aus den elektromagnetischen Feldstarkefunktionen. Wir erweitern das Zustandsschema von 158Yb bis zu I = 37 unter Benutzung der Reaktion 98Mo (64Ni, 4n) und diskutieren das Phanomen der Ruckbiegung an Yb-Isotopen.

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