0000000000060856
AUTHOR
E Makela
showing 16 related works from this author
High-spin levels in 63 145 Eu82
1996
The level scheme of theN=82 nucleus145Eu has been extended toI=(55/2) andEx=11.2 MeV in an experiment with the Tessa Compton-suppressed Ge detector array using the127I(22Ne,4n) reaction. Most of the complicated and irregular level scheme of145Eu can be interpreted as proton multi-quasiparticle states in comparison to the64146Gd82 core nucleus but also excitations across the neutronN=82 core have been observed.
Maximum spin aligned states in 98 47Ag51
1998
New excited states have been observed in the neutron deficient isotope Ag-98 following the Ni-58+Cr-50-->Te-108* heavy-ion reaction. One of these states may be interpreted as a maximum spin aligned state of the pi g(9/2)(-3) nu vg(7/2) configuration. Other possible interpretations within the nuclear shell model are discussed as well.
Highly deformed band inAg105
1995
The isotope Ag-105 has been studied using 169.5 MeV Cl-37 ions impinging on Ge-76. The Nordball Ge array detected the gamma rays and a 4 pi charged particle detector system detected emitted light charged particles. A very deformed band has been established using Doppler shift attenuation methods. The analysis is based on the gamma gamma coincidences and the angular dependence of the four rings of Ge detectors in Nordball. The deformation of the band is deduced to be beta(2)=0.37(-0.02)(+0.03).
In-beam γ-ray spectroscopy of 102Cd
1997
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 calculatio…
High-spin studies of the neutron deficient nuclei 103In, 105In, 107In, and 109In
1997
High-spin states of the isotopes In-103,In-105,In-107,In-109 have been investigated using in-beam gamma-ray spectroscopic methods. Results from three different experiments are presented. Targets of Fe-54, Cr-50, and Mo-92 were bombarded by a 270 and 261 MeV Ni-58 beam and by a 95 MeV F-19 beam, respectively. Reaction channel separation was achieved with a charged-particle detector array and in the first two experiments also with a 1 pi neutron detector system. As a result of these experiments the level schemes of In-103,In-105,In-107,In-109 were significantly extended. Excited states of these odd-A indium isotopes are discussed within the framework of the nuclear shell model and the hole-co…
In-beam γ-ray spectroscopy of 103Cd
1997
Excited states of Cd-103 were studied in the reaction Ni-58(Cr-50,4pn)Cd-103. The NORDBALL array with neutron and charged particle detectors was employed for the detection of gamma rays and light evaporated particles. The level scheme of Cd-103 was significantly extended. A strong cascade of E2 transitions connecting negative parity states was found, Shell model calculations were performed and positive parity excited states were interpreted in terms of neutron-particle and proton-hole excitations with respect to the doubly magic N = Z = 50 core. The negative parity band was well reproduced by the total routhian surface calculations. (C) 1997 Elsevier Science B.V.
Collective and broken pair states of65,67Ga
1999
Excited states of 65Ga and 67Ga nuclei were populated through the 12C(58Ni,αp) and 12C(58Ni,3p) reactions, respectively, and investigated by in-beam γ-ray spectroscopic methods. The NORDBALL array equipped with a charged particle ball and 11 neutron detectors was used to detect the evaporated particles and γ rays. The level schemes of 65,67Ga were constructed on the basis of γγ-coincidence relations up to 8.6 and 10 MeV excitation energy, and Iπ=27/2 and 33/2+ spin and parity, respectively. The structure of 65,67Ga nuclei was described in the interacting boson-fermion plus broken pair model, including quasiproton, quasiproton-two-quasineutron, and three-quasiproton fermion configurations in…
Structure of high-spin states in Pd
2001
High-spin states of the neutron deficient (100)pd nucleus have been investigated via the Cr-50(Ni-58, 4p alpha) and Zn-70(S-36,6n) heavy-ion induced reactions. For the detection of evaporated particles and gamma rays the NORDBALL array equipped with ancillary detectors and the EUROGAM II detector system were utilized. By the use of in-beam spectroscopic methods 89 transitions belonging to (100)pd have been observed, 49 of which were identified for the first time. The level scheme has been extended up to E-X approximate to 16 MeV excitation energy and I approximate to 25h. The experimental results were compared with the predictions of cranked shell model calculations. Maximal spin alignments…
Coexisting structures in 119I
1997
Abstract High-spin structures of 119 I have been studied by using 13 C and 15 N induced reactions. In all, fifteen ΔI = 1 or 2 bands belonging to 119 I were found. No evidence was found for bands with collective oblate shape, instead, all the observed rotational bands were interpreted to possess a collective prolate shape. A rich tapestry of noncollective states of both negative and positive parity was observed. Based on TRS calculations various configurations at β 2 ≈ 0.17 and γ = 60° were assigned to these states.
Structure of 68As studied via the 12C(58Ni,pn) reaction
1998
Excited states of As-68 nucleus were populated through the C-12(Ni-58,pn) reaction and investigated by in-beam gamma-spectroscopic methods. The NORDBALL detector array equipped with charged particle and neutron detectors was used to detect the evaporated particles and gamma-rays. The level scheme of As-68 was constructed on the basis of gamma gamma-coincidence relations up to 6 MeV excitation energy and J(pi) = (15(+)). The structure of the nucleus is discussed in the framework of the interacting boson-fermion-fermion model. The states below 2.3 MeV are described as members of proton-neutron-phonon multiplets. (C) 1998 Elsevier Science B.V.
Coexistence of collective and quasiparticle structures in 106Sn and 108Sn
1997
New levels in the neutron deficient nuclei 106Sn and 108Sn 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 d52, g72 and h112 both for protons and neutrons and g92 for protons. The systematical behaviour of the specific states in the Sn isotopes is studied in the mass range of A = 106–118.
Maximally aligned states in $^{99}$Ag
2003
Excited states of Ag-99 were populated via the Cr-50 + Ni-58 (261 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron. detector systems for reaction channel separation. On the basis of the measured gammagamma-coincidence relations and angular distribution ratios a significantly extended level scheme has been constructed up to E-x similar to 7.8 MeV and I = 35/2. The experimental results were described within the framework of the shell model. Candidates for states fully aligned in the pig(9/2)(-3)nu(d(5/2),g(7/2))(2) valence configuration space were found at 4109 and 6265 keV.
Band-terminating states in 101Ag
2004
Excited states of the neutron deficient Ag-101 nucleus have been investigated via the Cr-50(Ni-58, 3rho1alpha) heavy-ion induced reaction at 261 meV by use of in-beam spectroscopic methods. On the basis of the measured gammagamma-cincidence relations and angular distribution ratios high-spin bands have been extended up to I-pi = 35/2(+), 45/2((-)) and (49/2(-)). The negative parity states at the highest energy have been interpreted as terminating non-collective oblate states in the framework of the Nilsson-Strutinsky cranking formalism.
Coexistence of collective and quasiparticle structures in 106, 108Sn nuclei
1995
New revels in two neutron deficient nuclei Sn-106.108 have been found by using the Nordball detector array extended with the arrangements of charged particle and neutron detectors. The excited stru ...
First evidence for excited states inIn101
1996
The first evidence for excited states in In-101 is presented. In-101 is the lightest In isotope observed in an in-beam experiment. Two gamma-ray transitions at 1309 and 341 keV, respectively, are s ...
Stability ofS50100n50Deduced from Excited States inC4899d51
1996
Excited states of neutron deficient nuclei close to Sn-100 were investigated in an in-beam spectroscopic experiment using the NORDBALL detector array. Excited states in Cd-99 were identified for the first time. The measured half-life of an isomeric state in Cd-99 indicates that the stability with respect to quadrupole shape changes is as large in Sn-100 as for other heavy doubly magic nuclei.