| 1. |
- Bruce, A. M., et al.
(author)
-
Two-neutron alignment and shape changes in As-69
- 2000
-
In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 6202:2
-
Journal article (peer-reviewed)abstract
- The nucleus As-69 was Studied using the Ca-40(S-32,3p)As-69 reaction at a beam energy of 105 MeV. An extension of the band built on the g(9/2) orbital was observed to exhibit a band crossing at a rotational frequency of 0.511 MeV with an associated alignment of 7 (h) over bar. This alignment is interpreted as being due to a pair of g(9/2) neutrons. Total Routhian surface calculations have been carried out which confirm that the shape of this nucleus changes from oblate at low spin to a triaxial prolate shape at intermediate spin.
|
|
| 2. |
- Yu, C. H., et al.
(author)
-
Comparison of Superdeformed Bands in 61Zn and 60Zn: Possible Evidence for T=0 Pairing
- 1999
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 60:3
-
Journal article (peer-reviewed)abstract
- The yrast superdeformed band in Zn-61 has been established using Si-28(Ar-36, 2pn)Zn-61 and Ca-40(Si-29, 2 alpha)Zn-61 fusion-evaporation reactions. The excitation energy of this band was determined via two transitions that link this band to the normally deformed states. Lifetime analysis of this band resulted in a quadrupole moment of Q(t) = 3.0 +/- (0.5)(0.4)e b, which corresponds to a deformation of beta(2) = 0.50+/-(0.07)(0.06). A comparison of the J((2)) dynamical moments of inertia of the yrast superdeformed band in Zn-61 with those in Zn-60 shows a nearly complete blocking of the observed alignment in Zn-60, indicating that T=0 proton-neutron pair correlations may be present in Zn-60. [S0556-2813(99)51109-6].
|
|
| 3. |
- Andersson, Lise-Lotte, et al.
(author)
-
Extensive Gamma-ray Spectroscopy of Normally and Superdeformed Structures in 61Cu
- 2008
-
In: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 36:3, s. 251-278
-
Journal article (peer-reviewed)abstract
- A largely extended experimental knowledge of the Cu-61(29)32 nucleus has been obtained from three experiments. Excited states in Cu-61 were produced via the fusion-evaporation reaction Si-28(Ar-36, 3p)Cu-61. In addition to the Ge array GAMMASPHERE, neutron and charged-particle detectors placed around the target position were used for high-performance particle spectroscopy. The constructed level scheme includes more than 160 energy levels and 320 gamma-ray transitions belonging to both normally deformed as well as superdeformed rotational structures. The multipolarities have been determined for the gamma-ray transitions and as a result spin-parity assignments are given for nearly all energy levels. Experimental results in the normally deformed region are compared with predictions from large-scale shell model calculations. The collective structures are compared with results from cranked Nilsson-Strutinsky calculations. The results reveal the need to modify the standard Nilsson parameters in the mass A similar to 60 region.
|
|
| 4. |
- Gellanki, Jnaneswari, et al.
(author)
-
Characterization of Superdeformed Bands in 62Zn
- 2009
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:5
-
Journal article (peer-reviewed)abstract
- Combined data from four fusion-evaporation reaction experiments were utilized to investigate deformed and superdeformed structures in Zn-62(30)32. Combination of the Gammasphere gamma-ray spectrometer and ancillary particle detection systems allowed for the connection of rotational bands to well-known, low-lying excited states in Zn-62, as well as spectroscopy of discrete high-spin states reaching excitation energies of E-x=42.5 MeV. Four well- or superdeformed bands in Zn-62 are characterized and described by means of cranked Nilsson-Strutinsky calculations.
|
|
| 5. |
- Johansson, Emma, et al.
(author)
-
Prompt Proton Decay and Deformed Bands in 56Ni
- 2008
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 77:6
-
Journal article (peer-reviewed)abstract
- High-spin states in the doubly magic N=Z nucleus Ni-56 have been investigated with three fusion-evaporation reaction experiments. New gamma-ray transitions are added, and a confirmation of a previously suggested prompt proton decay from a rotational band in Ni-56 into the ground state of Co-55 is presented. The rotational bands in Ni-56 are discussed within the framework of cranked Nilsson-Strutinsky calculations.
|
|
| 6. |
- Svensson, C. E., et al.
(author)
-
Collective rotational motion in the N=Z nucleus 36Ar
- 2001
-
In: Nuclear Physics A. - 0375-9474. ; 682:1-4, s. 1-11
-
Journal article (peer-reviewed)abstract
- A superdeformed rotational band has been identified in the N = Z nucleus 36Ar, firmly linked to known low-spin states, and observed to its high-spin termination at Iπ = 16+. Lifetime measurements by the Doppler shift attenuation method establish a large low-spin deformation (β2 ≈ 0.46) and a decrease in the collectivity as the band approaches termination. Comparisons with cranked Nilsson-Strutinsky and large-scale spherical shell model calculations lead to a consistent description of the band based on a configuration in which four particles are promoted to the pf shell. With two major shells active for both protons and neutrons, yet a valence space dimension small enough to be approached from the shell model perspective, this band offers an excellent opportunity to investigate the microscopic structure of collective rotational motion in nuclei.
|
|
| 7. |
- Svensson, C. E., et al.
(author)
-
Decay Out of the Doubly Magic Superdeformed Band in the N=Z Nucleus 60Zn
- 1999
-
In: Physical Review Letters. - 1079-7114. ; 82:17, s. 3400-3403
-
Journal article (peer-reviewed)abstract
- The doubly magic superdeformed band in the N = Z nucleus Zn-60 has been identified. Linking transitions connecting this band to the yrast line provide the first spin, parity, and excitation energy measurements for superdeformed states in the A similar to 60 region. The stretched-E2 character and relatively large B(E2) values of these transitions suggest a nonstatistical decay-out process.
|
|
| 8. |
- Svensson, C. E., et al.
(author)
-
Smooth Termination of Rotational Bands in 62Zn: Evidence for a Loss of Collectivity
- 1998
-
In: Physical Review Letters. - 1079-7114. ; 80:12, s. 2558-2561
-
Journal article (peer-reviewed)abstract
- Two sets of strongly coupled rotational bands have been identified in Zn-62. These bands have been observed up to the terminating states of their respective configurations. Lifetime measurements indicate that the transition quadrupole moments in these bands decrease as termination is approached. These results establish the first terminating states of rotational bands in the A similar to 60 mass region and confirm the predicted loss of collectivity associated with smooth band termination.
|
|
| 9. |
- Svensson, C. E., et al.
(author)
-
Superdeformation in the N = z Nucleus 36Ar : Experimental, deformed mean field, and spherical shell model descriptions
- 2000
-
In: Physical Review Letters. - 0031-9007. ; 85:13, s. 2693-2696
-
Journal article (peer-reviewed)abstract
- A superdeformed rotational band has been identified in 36Ar, linked to known low-spin states, and observed to its high-spin termination at Iπ = 16+. Cranked Nilsson-Strutinsky and spherical shell model calculations assign the band to a configuration in which four pf-shell orbitals are occupied, leading to a low-spin deformation β2 ≈ 0.45. Two major shells are active for both protons and neutrons, yet the valence space remains small enough to be confronted with the shell model. This band thus provides an ideal case to study the microscopic structure of collective rotational motion.
|
|
| 10. |
- Torres, D. A., et al.
(author)
-
Deformations and Magnetic Rotations in the 60Ni Nucleus
- 2008
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:5
-
Journal article (peer-reviewed)abstract
- Data from three experiments using the heavy-ion fusion evaporation-reaction Ar-36+Si-28 have been combined to study high-spin states in the residual nucleus Ni-60, which is populated via the evaporation of four protons from the compound nucleus Ge-64. The GAMMASPHERE array was used for all the experiments in conjunction with a 4 pi charged-particle detector arrays (MICROBALL, LUWUSIA) and neutron detectors (NEUTRON SHELL) to allow for the detection of. rays in coincidence with the evaporated particles. An extended Ni-60 level scheme is presented, comprising more than 270 gamma-ray transitions and 110 excited states. Their spins and parities have been assigned via directional correlations of gamma rays emitted from oriented states. Spherical shell-model calculations in the fp-shell characterize some of the low-spin states, while the experimental results of the rotational bands are analyzed with configuration-dependent cranked Nilsson-Strutinsky calculations.
|
|
