Onset of collectivity in tellurium nuclei
- Argonne National Lab., IL (United States)
An open problem in nuclear structure physics is to understand the microscopic variables that determine the transition from single-particle to collective modes. Near shell closures, the low-lying nuclear structure is expected to be dominated by single-particle excitations, while collective modes dominate as the number of valence particles of both types is increased. In magic nuclei, deformed shapes arise from excitations across the major shell gaps, which again increases the number of valence nucleons. For Te isotopes with 2 valence protons, proton excitations across the Z=50 shell gap increases the number of valence protons and could lead to deformed configurations at higher excitation energies. Also, as the number of valence neutrons increases, there is a transition from pure single-particle excitations in the semi-magic {sup 134}Te to a collective vibrational structure for {sup 122}Te. In this transitional region, the experimental yrast 6{sup +} energies remain relatively constant, an indication of non-collectivity, while the experimental BE(E2; 2{r_arrow}0) values suggest that the yrast 2{sup +} state is vibrational. These data are interpreted in terms of the collective Interacting Boson Model, and in tandem with shell model arguments, suggest that the proton-neutron interaction and the valence orbits determine the onset of collectivity as a function of the spin of the excited states.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- DOE Contract Number:
- W-31-109-ENG-38
- OSTI ID:
- 243843
- Report Number(s):
- CONF-9304297-; ISSN 0003-0503; TRN: 96:002199-0362
- Journal Information:
- Bulletin of the American Physical Society, Vol. 38, Issue 2; Conference: 1993 joint meeting of the American Physical Society and the American Association of Physics Teachers, Washington, DC (United States), 12-15 Apr 1993; Other Information: PBD: Apr 1993
- Country of Publication:
- United States
- Language:
- English
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