| 61. |
- Ragnarsson, Ingemar, et al.
(författare)
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Building angular momentum beyond band termination in 157,158Er
- 2006
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Ingår i: ; , s. 66-75
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Our present understanding of the terminating bands in the I=40-50 spin range of 157,158Er is reviewed briefly. It is only recently that it has been possible to study states at higher spin in these nuclei, beyond band termination. Firstly, a large number of weak high-energy transitions feeding the terminating states were observed. Secondly, some collective structures that extended discrete spectroscopy in these nuclei beyond I= 60 hbar were identified.
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| 62. |
- Ragnarsson, Lars-Åke, 1968, et al.
(författare)
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Low temperature oxides deposited by remote plasma enhanced CVD
- 1994
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Ingår i: Proceedings of the Second International Symposium on Ultra-Clean Processing of Silicon Surfaces (UCPSS '94). ; , s. 117-
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Tidskriftsartikel (refereegranskat)abstract
- A remote plasma enhanced chemical vapor deposition (RPECVD) process was used to prepare SiO2-Si structures at ~300°C. The best midgap interface trap densities, Ditm, as obtained by C-V techniques are 6-8×1010 cm-2eV-1 for SiO2-Si(100) and 2-3×1011 cm-2eV-1 for SiO2-Si(111)
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| 63. |
- Rainovski, G, et al.
(författare)
-
Shape coexistence at high spin in the N = Z+2 nucleus Se-70
- 2002
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Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899. ; 28:10, s. 2617-2625
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Tidskriftsartikel (refereegranskat)abstract
- The nucleus Se-70 was studied using the Ca-40(Ca-40, 2alpha2p) reaction at a beam energy of 185 MeV. Gamma rays were measured with the EUROBALL III spectrometer. The known positive-parity bands have been extended and one new band of positive parity and two of negative parity have been identified. These bands are interpreted in terms of the cranked Nilsson-Strutinsky approach. Calculations suggest that the two negative-parity bands, which have the same signature, are both based on a configuration with two protons and three neutrons lifted from the fp shell to the g(9/2) orbital, but at different nuclear shapes. This represents a shape coexistence at high spin.
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| 64. |
- Rudolph, Dirk, et al.
(författare)
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Rotational Bands in the Semi-magic Nucleus 57Ni
- 2010
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Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 37:7
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Tidskriftsartikel (refereegranskat)abstract
- Two rotational bands have been identified and characterized in the proton-magic N = Z + 1 nucleus Ni-57. These bands complete the systematics of well-and superdeformed rotational bands in the light nickel isotopes starting from doubly magic Ni-56 to Ni-60. High-spin states in Ni-57 have been produced in the fusion-evaporation reaction Si-28(S-32, 2p1n)Ni-57 and studied with the gamma-ray detection array GAMMASPHERE operated in conjunction with detectors for evaporated light charged particles and neutrons. The features of the rotational bands in Ni-57 are compared to those of neighbouring isotopes and interpreted by means of configuration-dependent cranked Nilsson-Strutinsky calculations. The two observed high-spin bands are considered signature partners and assigned to configurations with one 1g(9/2) proton and one 1g(9/2) neutron, resulting in an unambiguous understanding of the energetically favoured signature alpha = -1/2 band but a somewhat less satisfactory description of the signature alpha = +1/2 band.
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| 65. |
- Rudolph, Dirk, et al.
(författare)
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Shell-model Influence in the Rotational Nucleus 86Mo
- 1996
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 54:1, s. 117-124
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Tidskriftsartikel (refereegranskat)abstract
- High-spin states in Mo-86 were studied by means of the fusion evaporation reaction Ni-58(S-32,2p2n) Mo-86 at 135 MeV beam energy. Charged-particle-gamma gamma and -gamma gamma gamma coincidences recorded with the early implementation of the GAMMASPHERE array and the MICROBALL charged-particle detection system were used to largely extend the level scheme of the T-tau=1 nucleus Mo-86 to a possible spin of I=24h at 13 MeV excitation energy. The excitation scheme is compared to neighboring nuclei. There is evidence for enhanced shell-model influence in the 4 quasiparticle region (I=12-16h). The observed (pi=+,alpha=0) sequence at spin I greater than or equal to 16 h appears to be associated with a triaxial collective rotational band. This interpretation is supported by calculations within the configuration-dependent shell-correction approach with the cranked Nilsson potential.
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| 66. |
- Sarantites, D. G., et al.
(författare)
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Triaxial superdeformed bands in [Formula Presented]
- 1998
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 57:1, s. 1-5
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Tidskriftsartikel (refereegranskat)abstract
- Four new superdeformed bands have been found in the nucleus [Formula Presented]. The good agreement between experiment and configuration-dependent shell correction calculations suggests that three of the bands have triaxial superdeformed shapes. Such unique features in mass [Formula Presented] superdeformed bands have been predicted, but not observed experimentally until now. A fourth band in [Formula Presented] is interesting due to a fairly constant and unusually high dynamic moment of inertia. Possible interpretations of this structure are discussed.
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| 67. |
- Sithole, M. A., et al.
(författare)
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Low- And medium-spin negative-parity bands in the Os 187 nucleus
- 2021
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Ingår i: Physical Review C. - 2469-9985. ; 103:2
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Tidskriftsartikel (refereegranskat)abstract
- Low- and medium-spin negative-parity bands of Os187 have been studied using the AFRican Omnipurpose Detector for Innovative Techniques and Experiments (AFRODITE) array, following the W186(He4,3n)Os187 reaction at a beam energy of 37 MeV. In the current work, all the previously known bands have been significantly extended and three new bands have been added to the level scheme. The angular distribution ratio (RAD) and polarization measurements have been used to assign spin and parity to the observed new levels. The configurations of some of the bands have been modified. The observed bands are interpreted within the cranked shell model (CSM) and cranked Nilsson-Strutinsky-Bogoliubov (CNSB) formalism. Comparison with experimental data shows good agreements. Systematic comparison with the neighboring Os185 isotope is also discussed.
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| 68. |
- Smith, J. F., et al.
(författare)
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Identification of excited states in 119Ba
- 2000
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 61:4
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Tidskriftsartikel (refereegranskat)abstract
- Excited states have been identified in the very neutron-deficient 119Ba nucleus. Two bands have been observed, which are likely to be based on h11/2 and (g7/2d5/2) neutron orbitals. Despite this being the first observation of excited states in 119Ba, the bands extend to (75/2)ℏ and (79/2)ℏ, respectively. The bands have been assigned to 119Ba using gamma-recoil and gamma-x-ray coincidences. Several quasiparticle alignments have been identified, involving neutron (h11/2)2 and proton (h11/2)2 aligned configurations. Furthermore, the bands show features which are reasonably consistent with smooth band termination at high spin. Theoretical results for 119Ba are discussed within the framework of cranked Woods-Saxon and Nilsson-Strutinsky calculations.
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| 69. |
- Starosta, K., et al.
(författare)
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Smooth band termination at high spin in 113I
- 2001
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 64:1, s. 143041-1430419
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Tidskriftsartikel (refereegranskat)abstract
- The 113I nucleus has been studied using the 58Ni(58Ni,3p) reaction at 250 MeV with the Gammasphere/ Microball facility. Gamma-ray three-and four-fold data gated by charged particle combinations were analyzed. Multipolarities of the γ rays were assigned following the angular correlation measurements. The present study is focused on the high spin properties, where the structure is dominated by 2p-2h excitations across the Z=50 gap. Ten decoupled bands showing the features of smooth band termination were observed; three of those bands are linked to known low-spin states, which allows the identification of configurations by direct comparisons with configuration-dependent cranked Nilsson-Strutinsky calculations. The yrast band, which was linked along with the signature partner, was followed up to (101/2+) and ℏω∼1.3 MeV. The other linked band was a negative-parity band observed up to (95/2-). Tentative configurations for the unlinked bands are discussed. Comparisons with the theoretical results suggest that the band built on a configuration involving the neutron i13/2 intruder orbital originating from the N=6 harmonic oscillator subshell was observed in this experiment.
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| 70. |
- Stefanescu, I, et al.
(författare)
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High-spin states and band terminations in As-69
- 2004
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 70:4
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Tidskriftsartikel (refereegranskat)abstract
- Excited levels in As-69 were studied using the Ca-40(S-32,3p)As-69 reaction at 95 and 105 MeV beam energy. Gamma rays were detected with the EUROBALL spectrometer operated in conjunction with the Neutron Wall and the charged-particle detector array EUCLIDES. New level sequences with positive and negative parity were identified from 3p-gammagamma and gammagammagamma coincidences. Spins were assigned to many of the levels on the basis of directional correlations of oriented states measurements. The previously observed positive-parity band was extended to spin 45/2(+) and it was found to exhibit a crossing with another configuration identified up to spin 53/2(+). Three negative-parity bands were observed for the first time up to spins (43/2(-)), 39/2(-), and (41/2(-)). The previously known band was extended to spin (49/2(-)). No evidence for superdeformation was found, despite very high counting statistics. Configurations were assigned to each of the observed bands through comparisons to the cranked Nilsson-Strutinsky calculations.
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