| 1. |
- Albers, M., et al.
(författare)
-
Single-particle and collective excitations in Ni 62
- 2016
-
Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 94:3
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Level sequences of rotational character have been observed in several nuclei in the A=60 mass region. The importance of the deformation-driving πf7/2 and νg9/2 orbitals on the onset of nuclear deformation is stressed. Purpose: A measurement was performed in order to identify collective rotational structures in the relatively neutron-rich Ni62 isotope. Method: The Mg26(Ca48,2α4nγ)Ni62 complex reaction at beam energies between 275 and 320 MeV was utilized. Reaction products were identified in mass (A) and charge (Z) with the fragment mass analyzer (FMA) and γ rays were detected with the Gammasphere array. Results: Two collective bands, built upon states of single-particle character, were identified and sizable deformation was assigned to both sequences based on the measured transitional quadrupole moments, herewith quantifying the deformation at high spin. Conclusions: Based on cranked Nilsson-Strutinsky calculations and comparisons with deformed bands in the A=60 mass region, the two rotational bands are understood as being associated with configurations involving multiple f7/2 protons and g9/2 neutrons, driving the nucleus to sizable prolate deformation.
|
|
| 2. |
- Albers, M., et al.
(författare)
-
Single-particle and collective excitations in Ni-63
- 2013
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 88:5
-
Tidskriftsartikel (refereegranskat)abstract
- A study of excited states in Ni-63 up to an excitation energy of 28 MeV and a probable spin of 57/2 was carried out with the Mg-26(Ca-48,2 alpha 3n gamma)Ni-63 reaction at beam energies between 275 and 320 MeV. Three collective bands, built upon states of single-particle character, were identified. For two of the three bands, the transition quadrupole moments were extracted, herewith quantifying the deformation at high spin. The results have been compared with shell-model and cranked Nilsson-Strutinsky calculations. Despite the Z = 28 shell closure and the approach to the purported N = 40 subshell, the Ni-63 isotope is able to sustain collective excitations at moderate and high spin.
|
|
