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Evidence for the wobbling mode in nuclei
S W Odegård1, G B Hagemann, D R Jensen
1The Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen Ø, Denmark.
Physical Review Letters
|June 21, 2001
Summary
Researchers studied the nucleus 163Lu using a fusion-evaporation reaction. They found evidence for a wobbling mode in excited triaxial, strongly deformed bands, linked to nuclear triaxiality.
Area of Science:
- Nuclear Physics
- Atomic Physics
Background:
- Investigating nuclear structures provides insights into fundamental forces.
- Triaxial, strongly deformed (TSD) bands are exotic nuclear states.
Purpose of the Study:
- To study electromagnetic properties of transitions between TSD bands in 163Lu.
- To identify and characterize complex excitation modes in deformed nuclei.
Main Methods:
- Fusion-evaporation reaction: 139La + 29Si at 152 MeV.
- Analysis of electromagnetic properties of gamma-ray transitions.
- Comparison with theoretical calculations of coupled particle-rotor models.
Main Results:
- Identified connecting transitions between two TSD bands in 163Lu.
- Presented evidence for an excited TSD band as a wobbling mode.
- The wobbling mode is built upon the yrast TSD band.
Conclusions:
- The observed excited TSD band is assigned as a wobbling mode.
- This finding supports the unique relationship between wobbling motion and nuclear triaxiality.
- The study advances the understanding of exotic shapes and excitation modes in atomic nuclei.
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