1. |
- Petrache, C. M., et al.
(author)
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Six-quasiparticle isomer in Nd-140
- 2006
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In: Physical Review C (Nuclear Physics). - 0556-2813. ; 74:3
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Journal article (other academic/artistic)abstract
- A search for isomeric states was performed in the nucleus Nd-140(60)80 using in-beam gamma-ray spectroscopy and the Te-126(O-18,4n) reaction. Prompt and delayed gamma-ray coincidences were measured with the AFRODITE spectrometer using the pulsed beam delivered by the Separated Sector Cyclotron of iThemba LABS. One new isomer was identified, with spin-parity I-pi=20(+) and lifetime T-1/2 >= 400 ns, at an excitation energy E-x=7430 keV. The lifetime of the 10(+) isomer at E-x=3619 keV was determined to be 32.9(1.8) ns, confirming the previously reported value. The configuration of the I-pi=20(+) isomer is assigned based on configuration-dependent cranked Nilsson-Strutinsky (CNS) calculations as a state pi(d(5/2)g(7/2))(10)(+-4)circle times nu(h(11/2)(-2))(10)(+), with the spin vectors of the six holes in the Gd-146(64)82 core fully aligned.
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2. |
- Lawrie, E. A., et al.
(author)
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Candidate chiral bands in Tl-198
- 2010
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In: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 45:1, s. 39-50
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Journal article (peer-reviewed)abstract
- High-spin states in Tl-198 were studied using the Au-197(alpha, 3n) reaction. The level scheme was considerably extended including two new bands and several non-yrast levels. One of the new bands is possibly a chiral partner to the yrast pi h(9/2) circle times vi(13/2)(-1) band. Two-quasiparticle-plus-triaxial-rotor model calculations suggest an aplanar orientation of the total angular momenta for these bands, thus supporting possible chirality.
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3. |
- Lawrie, E. A., et al.
(author)
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Possible chirality in the doubly-odd Tl-198 nucleus: Residual interaction at play
- 2008
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In: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:2
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Journal article (peer-reviewed)abstract
- A candidate for chiral bands was found in Tl-198 for the first time in a mass region of oblate (or nonaxial with gamma >= 30 degrees) deformed nuclei. Two bands show very similar quasiparticle alignments, moments of inertia, and B(M1)/B(E2) ratios. They have a relative excitation energy of about 500 keV and different patterns of energy staggering. Calculations using the two-quasiparticle-plus-triaxial-rotor model with residual proton-neutron interaction included show that a triaxial deformation with gamma similar to 44 degrees agrees very well with all the experimental observations. Furthennore, considerable energy staggering for both partner bands was calculated for this pi h(9/2) circle times vi(13/2)(-1) configuration at gamma - 30 degrees, suggesting that chiral bands may have substantial energy staggering.
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4. |
- Masiteng, P. L., et al.
(author)
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Close near-degeneracy in a pair of four-quasiparticle bands in Tl-194
- 2013
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In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 83-88
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Journal article (peer-reviewed)abstract
- A pair of rotational bands associated with the pi h(9/2) circle times nu i(13/2)(-1) configuration at lower spins and with the pi h(9/2) circle times nu i(13/2)(-3) configuration at higher spins is found in Tl-194. The two 4-quasiparticle bands show exceptionally close near-degeneracy in the excitation energies. Furthermore close similarity is also found in their alignments and B(M1)/B(E2) reduced transition probability ratios. Such close near-degeneracy probably indicates chiral geometry in the angular momentum space. (c) 2013 Elsevier B.V. All rights reserved.
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