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Evidence for collective oblate rotation in N = Z 68Se
1Department of Physics, DePaul University, Chicago, Illinois 60614, USA.
Physical Review Letters
|September 16, 2000
Summary
Researchers studied the N=Z nucleus 68Se using gamma-ray spectroscopy. They observed distinct oblate and prolate rotational bands, supporting predictions of oblate ground states in this nuclear region.
Area of Science:
- Nuclear Physics
- Spectroscopy
- Nuclear Structure
Background:
- The N=Z nucleus 68Se is of interest for understanding nuclear structure.
- Theoretical models predict significant oblate deformation in this region.
Purpose of the Study:
- To experimentally investigate the nuclear structure of 68Se.
- To identify and characterize rotational bands in 68Se.
Main Methods:
- Gamma-ray spectroscopy was employed using the Gammasphere array.
- The 12C(58Ni,2n) reaction was used at 185 and 220 MeV.
- The Argonne Fragment Mass Analyzer aided in the detection.
Main Results:
- Two distinct rotational bands were identified in 68Se.
- The ground state band exhibited characteristics of oblate collective rotation.
- An excited band showed characteristics consistent with prolate rotation.
Conclusions:
- The experimental findings support theoretical predictions of oblate ground states in 68Se.
- The coexistence of oblate and prolate shapes provides insights into nuclear dynamics.
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