| 1. |
- Sohler, D, et al.
(författare)
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Neutron Excitations Across the N=50 Shell Gap in 102In
- 2002
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Ingår i: Nuclear Physics, Section A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 708:3-4, s. 181-189
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Tidskriftsartikel (refereegranskat)abstract
- The structure of In-102 has been investigated by in-beam gamma-spectroscopic methods. Knowledge on the excited states of this nucleus has significantly been extended. Three cascades of transitions were observed to exceed the spin-energy domain spanned by the pig(9/2)(-1)v(d(5/2),g(7/2))(3) configurations. The new high spin states at similar to 4 MeV excitation energy could be assigned to the pig(9/2)(-1)v(d(5/2), g(7/2))(2)h (11/2) configuration, while at least those at 4.733, 5.192 and 5.853 MeV most likely arise from the vg(9/2) --> vd(5/2), g(7/2) one-particle-one-hole excitation across the N = 50 shell closure.
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| 2. |
- CEDERKALL, J, et al.
(författare)
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1ST OBSERVATION OF EXCITED-STATES IN SB-108
- 1995
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Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 581:1, s. 189-204
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Tidskriftsartikel (refereegranskat)abstract
- A spectroscopic study of Sb-108 has been carried out as a part of a larger experiment where in total twenty-nine different residual nuclei were identified. This study gives the first information on excited levels in this nucleus. A low-lying two-quasi-particle multiplet together with some of the higher lying levels are discussed within the framework of the nuclear shell model. A rotational, strongly coupled, band is identified as, most likely, being built on the deformed pig9/2(-1) nuh11/2 configuration in accordance with total routhian surface calculations. Tentative spins and parities are presented as well as B(M1)/B(E2) ratios for some of the transitions in the strongly coupled band.
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| 3. |
- FAHLANDER, C, et al.
(författare)
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IN-BEAM SPECTROSCOPY OF TE-110
- 1994
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Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 577:3-4, s. 773-785
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Tidskriftsartikel (refereegranskat)abstract
- The neutron-deficient nucleus Te-110 has been investigated by in-beam spectroscopic methods using the NORDBALL multi-detector array. Except for the energy of one level observed in alpha-decay, excited states in Te-110 were previously unknown. The level scheme constructed from gamma gamma-coincidence relationships is presented with tentative spin assignments up to I-pi = 21(-). Above spin 8(+) the yrast states have negative parity. They are most likely the members of a band predominantly based on the nu(h(11/2)g(7/2)) two-quasiparticle configuration. A band crossing is observed at I-pi approximate to 17(-). It is suggested to be caused by the alignment of two h(11/2) neutrons. The cranked shell model correctly predicts the spin alignment, but fails to reproduce the observed band crossing frequency, possibly because of octupole effects.
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| 4. |
- JERRESTAM, D, et al.
(författare)
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COLLECTIVE EXCITATIONS IN CD-106
- 1994
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 571:2, s. 393-412
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Tidskriftsartikel (refereegranskat)abstract
- High Spin states in 106Cd were populated by the reactions Zr-94(O-17, 5n) and Ge(S-32, 4n) at 80 MeV and at 148 MeV, respectively. The gamma-decay was studied by gamma-spectroscopic methods using the Nordball multi-detector army. Protons and alpha-particles were detected in particle detector system, thus selecting the neutron channel. The experiment included gamma-ray yields, gammagamma-coincidences and gamma-ray angular relation measurements. Collective bands extending up to spin 26+, 20- and 21-, have been observed in 106Cd. A new lifetime Of 11(-3)+6 ns for the 16+ state at 7118.7 keV has been found. Both total Routhian surfaces and spin diabatic surfaces have been calculated and used for assigning quasiparticle configurations to the bands. The (+, 0) band is assigned as a nuh11/2(2) configuration below I = 16+ and at higher spins suggested to be built on a pig9/2(2)nuh11/2(2) configuration. The large hindrance observed for the decay from the 16+ state supports the latter assignment. With the alignment of the nuh11/12(2) pair the deformation is predicted to change from (epsilon2,gamma) = (0.13,-2-degrees) to (0.17, 4-degrees). The configuration of the negative parity bands is assigned as either a nuh11/2(1)d5/2(1) or a nuh11/2(1)(g7/2xd5/2)1, With (epsilon2, gamma) = (0.14,9-degrees.
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| 5. |
- Juutinen, S, et al.
(författare)
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Coexistence of collective and quasiparticle structures in Sn-106 and Sn-108
- 1997
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Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 617:1, s. 74-90
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Tidskriftsartikel (refereegranskat)abstract
- New levels in the neutron deficient nuclei Sn-106 and Sn-108 have been investigated by using the NORDBALL detector array combined with charged particle and neutron detectors. The excited structures are discussed in terms of collectivity and the shell model. The excitations are interpreted to be based on d5/2, g7/2 and h(11/2) both for protons and neutrons and g(9/2) for protons. The systematical behaviour of the specific states in the Sn isotopes is studied in the mass range of A = 106-118.
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| 6. |
- Kownacki, J, et al.
(författare)
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High-spin studies of the neutron deficient nuclei In-103, In-105, In-107, and In-109
- 1997
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Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 627:2, s. 239-258
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Tidskriftsartikel (refereegranskat)abstract
- High-spin states of the isotopes 103,105,107,109In have been investigated using in-beam γ-ray spectroscopic methods. Results from three different experiments are presented. Targets of 54Fe, 50Cr, and 92Mo were bombarded by a 270 and 261 MeV 58Ni beam and by a 95 MeV 19F beam, respectively. Reaction channel separation was achieved with a charged-particle detector array and in the first two experiments also with a 1π neutron detector system. As a result of these experiments the level schemes of 103,105,107,109In were significantly extended. Excited states of these odd-A indium isotopes are discussed within the framework of the nuclear shell model and the hole-core coupling scheme. The systematics of excited states of light odd-A indium isotopes is also discussed.
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| 7. |
- Palacz, M, et al.
(författare)
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In-beam gamma-ray spectroscopy of Co-56
- 1997
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Ingår i: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 627:1, s. 162-174
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Excited states of Co-56 were studied in the reaction Al-27(S-32,2p1n) Co-56. The NORDBALL array with a Neutron Wall and a Silicon Ball was employed. The excited states were interpreted in terms of particle-hole excitations with respect to the doubly magic
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| 8. |
- Persson, J, et al.
(författare)
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In-beam gamma-ray spectroscopy of Cd-102
- 1997
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Ingår i: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 627:1, s. 101-118
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Tidskriftsartikel (refereegranskat)abstract
- Neutron deficient nuclei close to 100Sn have been studied using the NORDBALL Ge-detector array together with ancillary particle detectors. Evaporation residues from the compound nucleus 108Te were identified with charged particle and neutron detectors. In this paper a considerable extension of the level scheme of the nucleus 102Cd is presented. The strongest cascade of the new level scheme reveals an irregular sequence of dipole transitions above Iπ = 10+ extending up to spin 17. A strongly populated rather regular side band consisting of four quadrupole transitions ranging from spin 9 to spin 17 was also discovered. This band was tentatively assigned negative parity. Shell model calculations were performed and a very good agreement with the experimental results was found. The excited states could successfully be interpreted as neutron particle and proton hole excitations with respect to the doubly closed core 50100Sn50.
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| 9. |
- SEWERYNIAK, D, et al.
(författare)
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IN-BEAM STUDY OF IN-102, IN-104 AND IN-106
- 1995
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Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 589:1, s. 175-200
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Tidskriftsartikel (refereegranskat)abstract
- Proton-rich odd-odd In isotopes have been investigated by in-beam spectroscopic methods using the NORDBALL detector array. A Ni-58 beam with an energy of 270 MeV was used to bombard a Fe-54 target. Separation of different reaction channels was achieved with a 4 pi charged-particle multi-detector set-up together with a 1 pi neutron detector wall placed in the forward direction. Excited states of the In-102 nucleus were identified for the first time as well as a set of negative-parity states in In-104. In In-106 the information about positive- and negative-parity states has been extended. The nuclei are discussed within the framework of the nuclear shell model, the interacting boson-fermion-fermion model and the systematics of the heavier odd-odd indium isotopes.
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| 10. |
- JERRESTAM, Dan, et al.
(författare)
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IN-BEAM SPECTROSCOPIC STUDIES OF THE NUCLEUS CD-105
- 1995
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Ingår i: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474. ; 593:2, s. 162-176
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Tidskriftsartikel (refereegranskat)abstract
- High spin states in Cd-105 have been studied using reactions Cd-106(p, pn), Cd-106(He-3, 2p2n), Zr-92(O-16, 3n) and Ge-76(S-34, 5n). The excited levels are dominated by a negative parity band structure up to spin 47/2(-) and a positive parity structure up
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