Nacher, E., Rubio, B., Algora, A., Cano-Ott, D., Tain, J. L., Gadea, A., et al. (2016). Observations of the Gamow-Teller resonance in the rare-earth nuclei above Gd-146 populated in beta decay. Phys. Rev. C, 93(1), 014308–13pp.
Abstract: The rare-earth region of the nuclear table around the quasi-doubly magic nucleus Gd-146 is one of the very few places in which the Gamow-Teller (GT) resonance can be populated in beta decay. The appropriate technique to study such a phenomenon is total absorption spectroscopy, thanks to which one can measure the B(GT) distribution in beta-decay experiments even when it is very fragmented and lies at high excitation energy in the daughter nucleus. Results on the GT resonance measured in the beta decay of the odd-Z, N = 83 nuclei Tb-148, Ho-150, and Tm-152 are presented in this work and compared with shell-model calculations. The tail of the resonance is clearly observed up to the limit imposed by the Q value. This observation is important in the context of the understanding of the “quenching” of the GT strength.
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Morales, A. I. et al, Gadea, A., & Algora, A. (2014). beta-decay studies of neutron-rich Tl, Pb, and Bi isotopes. Phys. Rev. C, 89(1), 014324–13pp.
Abstract: The fragmentation of relativistic uranium projectiles has been exploited at the Gesellschaft fur Schwerionenforschung laboratory to investigate the beta decay of neutron-rich nuclei just beyond Pb-208. This paper reports on beta-delayed gamma decays of Tl211-213, Pb-215, and Bi215-219 de-exciting states in the daughters Pb211-213, Bi-215, and Po215-219. The resulting partial level schemes, proposed with the help of systematics and shell-model calculations, are presented. The role of allowed Gamow-Teller and first-forbidden beta transitions in this mass region is discussed.
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Morales, A. I. et al, Agramunt, J., Algora, A., Gadea, A., Molina, F., & Rubio, B. (2011). Synthesis of N=127 isotones through (p,n) charge-exchange reactions induced by relativistic (208)Pb projectiles. Phys. Rev. C, 84(1), 011601–5pp.
Abstract: The production cross sections of four N = 127 isotones ((207)Hg, (206)Au, (205)Pt, and (204)Ir) have been measured using (p,n) charge-exchange reactions, induced in collisions of a (208)Pb primary beam at 1 A GeV with a Be target. These data allow one to investigate the use of a reaction mechanism to extend the limits of the chart of nuclides toward the important r-process nuclei in the region of the third peak of elemental abundance distribution.
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Montanari, D., Farnea, E., Leoni, S., Pollarolo, G., Corradi, L., Benzoni, G., et al. (2011). Response function of the magnetic spectrometer PRISMA. Eur. Phys. J. A, 47(1), 4–7pp.
Abstract: The response function of the magnetic spectrometer PRISMA is studied via a Monte Carlo simulation that employs a ray tracing code to determine the trajectories of individual rays through the electromagnetic fields. The calculated response is tested on angular and energy distributions provided by theoretical calculations for the Ca-48 + Ni-64 multinucleon transfer reaction and applied to the corresponding experimental data.
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Montanari, D. et al, & Gadea, A. (2011). Probing the nature of particle-core couplings in Ca-49 with gamma spectroscopy and heavy-ion transfer reactions. Phys. Lett. B, 697(4), 288–293.
Abstract: Neutron rich nuclei around Ca-48 have been measured with the CLARA-PRISMA setup, making use of Ca-48 on Ni-64 binary reactions, at 5.9 MeV/A. Angular distributions of gamma rays give evidence, in several transfer channels, for a large spin alignment (approximate to 70%) perpendicular to the reaction plane, making it possible to firmly establish spin and parities of the excited states. In the case of Ca-49, states arising from different types of particle-core couplings are, for the first time, unambiguously identified on basis of angular distribution, polarization and lifetime measurements. Shell model and particle-vibration coupling calculations are used to pin down the nature of the states. Evidence is found for the presence, in the same excitation energy region, of two types of coupled states, i.e. single particle coupled to either Ca-48 or Ca-50 simple configurations, and particle-vibration coupled states based on the 3- phonon of Ca-48.
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