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Collectivity and configuration mixing in 186,188Pb and 194Po.
1Department of Physics, University of Jyväskylä, P. O. Box 35, FI-40014 Jyväskylä, Finland.
Physical Review Letters
|October 10, 2006
Summary
Researchers measured nuclear lifetimes for prolate and oblate states in lead (Pb) and polonium (Po) isotopes. This study provides new insights into nuclear shape mixing and deformation parameters.
Area of Science:
- Nuclear Physics
- Atomic Physics
- Quantum Mechanics
Background:
- Understanding nuclear structure and shapes is crucial in nuclear physics.
- Intruder states in heavy nuclei offer insights into shape coexistence and transitions.
- Previous lifetime measurements have provided limited data on these specific isotopes.
Purpose of the Study:
- To determine the lifetimes of prolate intruder states in 186Pb and oblate intruder states in 194Po.
- To measure lifetimes of prolate states in 188Pb up to the 8+ state.
- To extract nuclear deformation parameters and investigate shape mixing.
Main Methods:
- Utilized the recoil-decay tagging technique for the first time in recoil distance Doppler-shift lifetime measurements.
- Employed the recoil-gating method for lifetime measurements in 188Pb.
- Deduced B(E2) values from the measured lifetimes.
Main Results:
- Lifetimes of prolate and oblate intruder states in 186Pb and 194Po were determined.
- Lifetimes for prolate states in 188Pb up to the 8+ state were measured.
- Deformation parameters |beta2|=0.29(5) for prolate bands and |beta2|=0.17(3) for oblate bands were extracted.
Conclusions:
- The extracted deformation parameters provide quantitative measures of nuclear shapes.
- The results offer new insights into the phenomenon of shape mixing in atomic nuclei.
- This study advances the understanding of nuclear structure in the lead and polonium isotopic regions.
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