Browsing by Author "Lindsay, R."

Now showing 1 - 5 of 5
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    Nuclear structure studies relevant to ¹³⁶Xe ββ decay
    (IOP Publishing, 2018) Rebeiro, B. M.; Triambak, S.; Garrett, P. E.; Lindsay, R.; Adsley, P.; Ball, G. C.; Bildstein, V.; Burbadge, C.; Diaz-Varela, A.; Faestermann, T.; Hertenberger, R.; Jigmeddorj, B.; Kamil, M.; Leach, K. G.; Mabika, P. Z.; Nzobadila, J. C.; Orce, J. N.; Radich, A. J.; Rand, E.; Wirth, H. F.
    In these proceedings we briefly discuss preliminary results from ¹³⁸Ba(d, α) and ¹³⁸Ba(p, t) reactions performed using the Q3D magentic spectrometer at the Maier-Leibnitz- Laboratorium (MLL) tandem accelerator facility in Garching, Germany. Our results aim to provide useful spectroscopic information for the calculation of the ¹³⁶Xe →¹³⁶ Ba double beta decay matrix elements.
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    Radon-222 measurements at Cape Point : a characterization of a 15-year time series
    (National Association for Clean Air, 2018) Botha, R.; Labuschagne, C.; Williams, A. G.; Bosman, G.; Brunke, E.-G.; Rossouw, A.; Lindsay, R.
    Radon-222 measurements at Cape Point: A characterization of a 15-year time series The Cape Point (CPT) Global Atmosphere Watch (GAW) research station have been monitoring climatically significant trace gases for four decades. Among these is radon, a naturally occurring noble gas with a large continental source, which has proven very useful for atmospheric tracer studies. 222 Rn, the radioactive decay daughter product of radon gas, forms part of the long-term exposure of radiation dosages that humans are continuously exposed to in the environment. In a first of its kind for the African continent, a radon climatology, based on a 15-year measurement record at CPT, was published in the Atmospheric Environment journal (www.elsevier.com/locate/ atmosenv).
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    Silver ion generation, deflection and deposition in vacuum
    (2011) Bam, L. C.; Dobson, Robert Thomas; Lindsay, R.
    ENGLISH ABSTRACT: The potential problems arising during the operation of a pebble bed modular type reactor has stimulated a number of research avenues in different fields. This study presents results of a first approach method of deflecting a silver ion beam, in vacuum. These results serve as a building block for the future research that needs to be conducted in helium. An experimental apparatus was constructed and it was found that theoretically predicted deflections corresponded to within about 20% of the experimental results. The test apparatus could also be used as a practical supplementing a Physic course.
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    Spectroscopy of low lying states in 136Cs
    (IOP Publishing, 2016) Rebeiro, B.; Triambak, S.; Lindsay, R.; Adsley, P.; Burbadge, C.; Ball, G.; Bildstein, V.; Faestermann, T.; Garrett, P. E.; Hertenberger, R.; Radich, A.; Rand, E.; Varela, A.; Wirth, H.-F.
    The low-lying excited states in 136Cs relevant to the double beta decay of 136Xe were studied via a 138Ba(d, α)136Cs transfer reaction with a high resolution magnetic spectrometer. Preliminary results from the experiment are presented.
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    β and γ bands in N = 88 , 90, and 92 isotones investigated with a five-dimensional collective Hamiltonian based on covariant density functional theory : vibrations, shape coexistence, and superdeformation
    (American Physical Society, 2019-06-05) Majola, S. N. T.; Shi, Z.; Song, B. Y.; Li, Z. P.; Zhang, S. Q.; Bark, R. A.; Sharpey-Schafer, J. F.; Aschman, D. G.; Bvumbi, S. P.; Bucher, T. D.; Cullen, D. M.; Dinoko, T. S.; Easton, J. E.; Erasmus, N.; Greenlees, P. T.; Hartley, D. J.; Hirvonen, J.; Korichi, A.; Jakobsson, U.; Jones, P.; Jongile, S.; Julin, R.; Juutinen, S.; Ketelhut, S.; Kheswa, B. V.; Khumalo, N. A.; Lawrie, E. A.; Lawrie, J. J.; Lindsay, R.; Madiba, T. E.; Makhathini, L.; Maliage, S. M.; Maqabuka, B.; Malatji, K. L.; Masiteng, P. L.; Mashita, P. I.; Mdletshe, L.; Minkova, A.; Msebi, L.; Mullins, S. M.; Ndayishimye, J.; Negi, D.; Netshiya, A.; Newman, R.; Ntshangase, S. S.; Ntshodu, R.; Msebi, L.; Mullins, S. M.; Ndayishimye, J.; Negi, D.; Netshiya, A.; Newman, R.; Ntshangase, S. S.; Ntshodu, R.; Nyako, B. M.; Papka, P.; Peura, P.; Rahkila, P.; Riedinger, L. L.; Riley, M. A.; Roux, D. G.; Ruotsalainen, P.; Saren, J. J.; Scholey, C.; Shirinda, O.; Sithole, M. A.; Sorri, J.; Stankiewicz, M.; Stolze, S.; Timar, J.; Uusitalo, J.; Vymers, P. A.; Wiedeking, M.; Zimba, G. L.
    A comprehensive systematic study is made for the collective β and γ bands in even-even isotopes with neutron numbers N = 88 to 92 and proton numbers Z = 62 (Sm) to 70 (Yb). Data, including excitation energies, B(E0) and B(E2) values, and branching ratios from previously published experiments are collated with new data presented for the first time in this study. The experimental data are compared to calculations using a five-dimensional collective Hamiltonian (5DCH) based on the covariant density functional theory (CDFT). A realistic potential in the quadrupole shape parameters V (β,γ ) is determined from potential energy surfaces (PES) calculated using the CDFT. The parameters of the 5DCH are fixed and contained within the CDFT. Overall, a satisfactory agreement is found between the data and the calculations. In line with the energy staggering S(I) of the levels in the 2γ + bands, the potential energy surfaces of the CDFT calculations indicate γ -soft shapes in the N = 88 nuclides, which become γ rigid for N = 90 and N = 92. The nature of the 02 + bands changes with atomic number. In the isotopes of Sm to Dy, they can be understood as β vibrations, but in the Er and Yb isotopes the 02 + bands have wave functions with large components in a triaxial superdeformed minimum. In the vicinity of 152Sm, the present calculations predict a soft potential in the β direction but do not find two coexisting minima. This is reminiscent of 152Sm exhibiting an X(5) behavior. The model also predicts that the 03 + bands are of two-phonon nature, having an energy twice that of the 02 + band. This is in contradiction with the data and implies that other excitation modes must be invoked to explain their origin.