Browsing by Author "Garrote, F. L. Bello"

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    ¹³⁷,¹³⁸,¹³⁹La(n,γ) cross sections constrained with statistical decay properties of ¹³⁸,¹³⁹,¹⁴⁰La nuclei
    (American Physical Society, 2017) Kheswa, B. V.; Wiedeking, M.; Brown, J. A.; Larsen, A. C.; Goriely, S.; Guttormsen, M.; Garrote, F. L. Bello; Bernstein, L. A.; Bleuel, D. L.; Eriksen, T. K.; Giacoppo, F.; Gorgen, A.; Goldblum, B. L.; Hagen, T. W.; Koehler, P. E.; Klintefjord, M.; Malatji, K. L.; Midtbo, J. E.; Nyhus, H. T.; Papka, P.; Renstrm, T.; Rose, S. J.; Sahin, E.; Siem, S.; Tornyi, T. G.
    The nuclear level densities and γ-ray strength functions of ¹³⁸,¹³⁹,¹⁴⁰La were measured using the ¹³⁹La(³He,α), ¹³⁹La(³He,'³He), and ¹³⁹La(d,p) reactions. The particle-γ coincidences were recorded with the silicon particle telescope (SiRi) and NaI(Tl) (CACTUS) arrays. In the context of these experimental results, the low-energy enhancement in the A∼140 region is discussed. The ¹³⁷,¹³⁸,¹³⁹La(n,γ) cross sections were calculated at s- and p-process temperatures using the experimentally measured nuclear level densities and γ-ray strength functions. Good agreement is found between ¹³⁹La(n,γ) calculated cross sections and previous measurements.
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    Nuclear level densities and γ-ray strength functions of 180,181,182Ta
    (American Physical Society, 2019) Brits, C. P.; Malatji, K. L.; Wiedeking, M.; Kheswa, B. V.; Goriely, S.; Garrote, F. L. Bello; Bleuel, D. L.; Giacoppo, F.; Gorgen, A.; Guttormsen, M.; Hadynska-Klek, K.; Hagen, T. W.; Hilaire, S.; Ingeberg, V. W.; Klintefjord, H. Jia M.; Larsen, A. C.; Majola, S. N. T.; Papka, P.; Peru, S.; Qi, B.; Renstrom, T.; Rose, S. J.; Sahin, E.; Siem, S.; Tveten, G. M.; Zeiser, F.
    Particle-γ coincidence experiments were performed at the Oslo Cyclotron Laboratory with the ¹⁸¹Ta(d,X) and ¹⁸¹Ta(³He,X) reactions to measure the nuclear level densities (NLDs) and γ-ray strength functions (γSFs) of ¹⁸⁰,¹⁸¹,¹⁸²Ta using the Oslo method. The back-shifted Fermi-gas, constant temperature plus Fermi gas, and Hartree-Fock-Bogoliubov plus combinatorial models were used for the absolute normalizations of the experimental NLDs at the neutron separation energies. The NLDs and γSFs are used to calculate the corresponding ¹⁸¹Ta(n,γ) cross sections and these are compared to results from other techniques. The energy region of the scissors resonance strength is investigated and from the data and comparison to prior work it is concluded that the scissors strength splits into two distinct parts. This splitting may allow for the determination of triaxiality and a γ deformation of 14.9˚±1.8˚ was determined for ¹⁸¹Ta.