1. |
- Perries, S, et al.
(author)
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Decay-out of the yrast superdeformed band in Nd-136 : Towards an experimental extraction of the neutron pairing gap at large deformation
- 1999
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In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 60:6
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Journal article (peer-reviewed)abstract
- A study of the Nd-136 nucleus has been performed with the EUROBALL III multidetector to establish the decay-out of the yrast superdeformed (SD) band. Three discrete linking transitions (754, 1456, and 1493 keV) have been discovered, establishing the position of the SD band at 7.03 MeV excitation energy with proposed spin and parity 17((-)) for the lowest observed SD state. Neutron pairing gap parameters for SD shapes have been extracted in Nd isotopes, using the strong-coupling model and odd-even mass difference formulas. The major conclusion of our phenomenological analysis is that the pairing correlations do subsist in the SD configurations of nuclei in the A = 130 mass region. [S0556-2813(99)01312-6].
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2. |
- De Angelis, G., et al.
(author)
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Collective Excitations in the Vicinity of N=Z
- 1999. - 1 SUPPL. 1
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In: Proceedings INPC 1998. - 0375-9474. ; 654, s. 659-662
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Conference paper (peer-reviewed)abstract
- In our contribution to the INPC98 conference we reported on the experimental investigation of high spin collective states in medium and heavy mass N≈Z nuclei at LNL. The main purpose is to set light on the role of the proton-neutron interaction in the collective behavior of the nucleus. In medium mass N=Z nuclei, in contrast with the stable nuclei, valence protons and neutrons occupy the same orbitals and one may expect a reinforcement of neutron-proton T=0 (np) pairing correlations[1]. In this interesting subject, the medium mass N=Z=36 72Kr has been studied and completely reported in [2]. In this proceedings we will concentrate in unpublished results concerning the onset of collectivity on nearly spherical nuclei in the 100Sn region. In nuclei with Z=50 and Z=49 dipole bands have been found indicating the presence of "Magnetic Rotation" [3].
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4. |
- Gadea, A., et al.
(author)
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Spectroscopy at N=Z with EUROBALL III
- 1999
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In: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. ; 495, s. 195-198
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Conference paper (peer-reviewed)abstract
- A complete study of the nuclear structure by means of gamma spectroscopy requires, in addition to the high resolution gamma measurement and accurate DCO's or angular distributions, the information concerning the Electric or Magnetic character of the transition. This information for transitions in nuclei far from stability valley is now reachable in the new generation of Ge-arrays based in composite detectors. EUROBALL III is a good example with the high polarization sensitivity of the 90 degrees ring of Clovers. The Polarization correlations PCO's measured in coincidence with the Cluster detectors permits to investigate transitions in weakly populated nuclei. In this contribution we present results on medium mass N=Z nuclei measured with EUROBALL III coupled with light particle ancillary detectors.
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5. |
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6. |
- Axelsson, A, et al.
(author)
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Excited superdeformed band in Eu-143
- 1999
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In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 6:2, s. 175-183
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Journal article (peer-reviewed)abstract
- A new superdeformed band has been discovered in a EUROBALL experiment and assigned to Eu-143. It has a maximum intensity of 35% of the Eu-143 yrast superdeformed band and the transition energies of the two bands are very similar. Based on comparison with cranked shell model calculations the new band is tentatively assigned the high-N intruder configuration pi 6(2)nu 7(0) and the parity and signature quantum numbers (pi, alpha) = (-1, +1/2). In addition to the already known high-energy transition at 3361 keV another discrete line at 2715 keV was found to be in coincidence with the yrast superdeformed band. However, it was not possible to connect the decay out of either of the superdeformed bands to, known normally deformed states.
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7. |
- Axelsson, A, et al.
(author)
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Excited superdeformed band in Eu-143
- 1999
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In: EUROPEAN PHYSICAL JOURNAL A. - : SPRINGER VERLAG. - 1434-6001. ; 6:2, s. 175-183
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Journal article (other academic/artistic)abstract
- A new superdeformed band has been discovered in a EUROBALL experiment and assigned to Eu-143. It has a maximum intensity of 35% of the Eu-143 yrast superdeformed band and the transition energies of the two bands are very similar. Based on comparison with
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8. |
- de, Angelis G, et al.
(author)
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Band crossing phenomena in N = Z nuclei - A probe to T = 0 pairing correlations?
- 1997
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In: ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS. - : AKADEMIAI KIADO. ; 6:1-4, s. 269-273
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Journal article (other academic/artistic)abstract
- The structure of the N = Z nuclei Zn-60, Ga-62, Ge-64 and Kr-72 has been investigated at GASP. Total Routhian surface (TRS) calculations have been performed for the N = 36, 38 and 40 Kr isotones. In the case of Kr-72 the four quasi-particle g(9/2) alignme
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9. |
- de, Angelis G, et al.
(author)
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Rotation induced octupole correlations in the neutron-deficient Te-109 nucleus
- 1998
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In: Physics Letters B. - 0370-2693 .- 1873-2445. ; 437:3-4, s. 236-242
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Journal article (peer-reviewed)abstract
- High spin states in the neutron deficient nucleus 109Te have been populated with the 58Ni+54Fe reaction at 220 MeV and investigated through γ-spectroscopy methods at the GASP spectrometer making use of reaction channel selection with the ISIS Si-ball. The level scheme has been extended up to an excitation energy of ≈12.1 MeV. The spins and parities of the observed levels are assigned tentatively supporting the identification of two bands of opposite parity connected by strong dipole transitions inferred to be of E1 character. Octupole correlations in 109Te induced by rotation are suggested as the cause of this effect.
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10. |
- Gadea, A, et al.
(author)
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Magnetic rotation in the Sn-105 nucleus
- 1997
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In: PHYSICAL REVIEW C-NUCLEAR PHYSICS. - : AMER INST PHYSICS. ; 55:1, s. R1-R4
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Journal article (other academic/artistic)abstract
- The structure of Sn-105 has been investigated through the Cr-50(Ni-58,2pn) reaction at a beam energy of 210 MeV. In addition to an extension of the spherical level scheme a regular sequence of dipole transitions has been found. The states of the dipole ba
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