| 1. |
- Cooper, M. W., et al.
(författare)
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New γ transitions in 27Na from 14C on 14C
- 2001
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Ingår i: Nuclear Physics A. - 0375-9474. ; 682:1-4, s. 131-135
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Tidskriftsartikel (refereegranskat)abstract
- The neutron rich 27Na was studied at Florida State University using the 14C(14C,p) reaction at 22 MeV. The 14C target was 0.28 mg/cm2 thick. γ-γ and particle-γ, coincidences were measured using 2 four-crystal clover detectors, 7 Compton-suppressed HPGe detectors, and a particle detector telescope at 0°. The 1757, 1823, and 2219 keV transitions are likely yrast transitions in 27Na. Based on systematics of neighboring nuclei, the first two lines probably arise from the decays of the 7/2+ and 9/2+ states. The results will be discussed in terms of both the shell model and the cranked Nilsson-Strutinsky rotational model.
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| 2. |
- Ma, W. C., et al.
(författare)
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Competition between terminating and collective structures above spin 40ℏ in 154Dy
- 2002
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 65, s. 1-034312
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Tidskriftsartikel (refereegranskat)abstract
- High-spin states in 154Dy were studied with the Gammasphere spectrometer using the 36S(122Sn,4n) reaction. Band terminating states were identified in the spin range I= (36-48)ℏ, and were found to compete with collective rotational cascades up to the highest observed spins. Several "sidebands" feeding the terminating structures were identified as well. A band dominated by M1 transitions was observed to terminate at Iπ = 42-. The data are interpreted within the framework of configuration-dependent cranked Nilsson-Strutinsky calculations without pairing.
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| 3. |
- Pfohl, J., et al.
(författare)
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Highly deformed rotational structures in 136Pm
- 2000
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 62:3, s. 313041-313045
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Tidskriftsartikel (refereegranskat)abstract
- Four highly deformed structures in the odd-odd nucleus 13661Pm75 were observed via the 105Pd(35Cl,2p2n) reaction at 180 and 173 MeV using the GAMMASPHERE γ-ray spectrometer and the Microball charged-particle detector array. Quadrupole moment measurements were performed on all of the bands. In contrast to lighter odd-Ζ Pm and Pr nuclei, bands based on the g9/2[404]9/2 proton orbital were not observed. Instead, the four observed sequences are assigned as a coupling of an i13/2 neutron with the low-Ω h11/2 and mixed d5/2g7/2 orbitals. Comparisons with neighboring highly deformed structures are discussed and cranked Nilsson-Strutinsky calculations for 136Pm are presented.
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| 4. |
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| 5. |
- Simpson, J., et al.
(författare)
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Discrete line γ-ray spectroscopy in the (50-60)ℏ spin domain of 161,162Er
- 2000
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 62:2, s. 243211-243218
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Tidskriftsartikel (refereegranskat)abstract
- Very high spin states (I=50-60ℏ) have been observed in the transitional nuclei 161Er and 162Er using the Euroball γ-ray spectrometer. In 161Er, three bands are observed well above spin 50ℏ. In the positive parity, positive signature (+, + 1/2) band a discontinuity in the regular rotational behavior occurs at 109/2+ and a splitting into two branches occurs at 97/2- in the negative parity, positive signature (-, + 1/2) band. The ( -, - 1/2) band continues in a regular fashion to 115/2-, tentatively (119/2-). In 162Er the positive parity, even spin (+, 0) yrast band is observed to continue smoothly up to 58+ (60+) and the negative parity, even spin (-,0) and odd spin (-,1) bands are extended from 30- to 34- and from 31- to 47- (49-), respectively. The high spin experimental spectra are compared with both a simple model involving the occupation of specific single neutron states in the absence of neutron pair correlations and with more detailed cranked Nilsson-Strutinsky calculations in which both proton and neutron pairing correlations are neglected. The very high spin domain is found to comprise a series of unpaired rotational bands. Unpaired band crossings between bands with different neutron and proton configurations are identified in 161Er. There is no evidence for aligned oblate or terminating states being close to the yrast line in 161,162Er up to spin ≈60ℏ in contrast to the lighter Er isotopes.
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| 6. |
- Tabor, S. L., et al.
(författare)
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Structure of neutron-rich s-d shell nuclei
- 2002
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Ingår i: Physics of Atomic Nuclei. - : Pleiades Publishing Ltd. - 1063-7788 .- 1562-692X. ; 65:4, s. 713-719
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Tidskriftsartikel (refereegranskat)abstract
- States in neutron-rich s-d shell nuclei were populated in the reaction of a 14C beam at Elab = 22 MeV on a 14C target. Coincidences between γ rays and either other γ rays or light charged particles were measured. γ rays in coincidence with protons established levels at 66.8, 1730, 1823, and 2219 keV in 27Na. The states are compared with calculations based on the s-d shell model and the cranked Nilsson-Strutinsky model. A number of levels in 24Ne were observed in both α-γ and α-γ-γ coincidences and are compared with shell-model calculations.
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