Spectroscopy at the Highest Spins in Normal Deformed Nuclei

作者: J. Simpson

DOI: 10.1007/978-1-4615-4257-5_58

关键词: Spin statesSpectroscopyAtomic orbitalAtomic physicsSpinsYrastPhysicsNeutronParity (physics)Gammasphere

摘要: Very high spin states (50-60ħ) have been observed in the transitional nuclei 156Dy and 158–162Er using γ-ray spectrometers Eurogam, Euroball Gammasphere. The lowest energy positive parity bands are found to evolve smoothly towards oblate shape contrast sudden change neighbouring nucleus 158Er. In 159Er, decay path of yrast fragments above \( {I^\pi } = {\frac{{85}}{2}^ + \) favoured single particle identified at {\frac{{89}}{2}^ \frac{{101 }}{2} \). 160Er structure is remain collective up beyond 50ħ with no sign band termination. 161Er three well 50ħ. even parity, signature (+,+\( \frac{{1}}{2} \)) a crossing near which interpreted an unpaired involving rearrangement occupation neutron orbitals. negative there evidence for proton orbitals possible These data on termination, crossings competition between these phenomena very spins will be discussed.

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