Doncel, M. et al, Gadea, A., & Huyuk, T. (2013). Lifetime measurements in neutron-rich Cu isotopes. Acta Phys. Pol. B, 44(3), 505–510.
Abstract: The nuclear structure of neutron-rich nuclei close to the double-magic nucleus Ni-78 has been investigated by measuring the lifetime of excited states. In this contribution, it will be presented the lifetime of the J(pi) = 7/2(-) excited state at 981 keV of the Cu-71 isotope, measured using the AGATA Demonstrator coupled to the PRISMA spectrometer and the Koln plunger setup. This is the first time this combined setup has been used for a lifetime measurement.
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Hadynska-Klek, K. et al, & Gadea, A. (2013). Towards the determination of superdeformation in Ca-42. Acta Phys. Pol. B, 44(3), 617–625.
Abstract: The Coulomb excitation experiment to study electromagnetic structure of low-lying states in Ca-42 with a focus on a possible superdeformation in this nucleus was performed at the Laboratori Nazionali di Legnaro in Italy. Preliminary values of the determined quadrupole deformation parameters for both the ground state band and the presumed superdeformed band are presented.
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Vandone, V. et al, Gadea, A., & Huyuk, T. (2013). Global properties of K hindrance probed by the gamma decay of the warm rotating W-174 nucleus. Phys. Rev. C, 88(3), 034312–9pp.
Abstract: The K hindrance to the gamma decay is studied in the warm rotating W-174 nucleus, focusing on the weakening of the selection rules of the K quantum number with increasing excitation energy. W-174 was populated by the fusion reaction of Ti-50 (at 217 MeV) on a Te-128 target, and its gamma decay was detected by the AGATA Demonstrator array coupled to a BaF2 multiplicity filter at Laboratori Nazionali di Legnaro of INFN. A fluctuation analysis of gamma coincidence matrices gives a similar number of low-K and high-K discrete excited bands. The results are compared to simulations of the gamma-decay flow based on a microscopic cranked shell model at finite temperature in which the K mixing is governed by the interplay of Coriolis force with the residual interaction. Agreement between simulations and experiment is obtained only by hindering the E1 decay between low-K and high-K bands by an amount compatible with that determined by spectroscopic studies of K isomers in the same mass region, with a similar trend with excitation energy. The work indicates that K mixing due to temperature effects may play a leading role for the entire body of discrete excited bands, which probes the onset region of K weakening.
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Gottardo, A. et al, Gadea, A., & Algora, A. (2014). Isomeric decay spectroscopy of the Bi-217 isotope. Phys. Rev. C, 90(3), 034317–6pp.
Abstract: The structure of the neutron-rich bismuth isotope Bi-217 has been studied for the first time. The fragmentation of a primary U-238 beam at the FRS-RISING setup at GSI was exploited to perform gamma-decay spectroscopy, since μs isomeric states were expected in this nucleus. Gamma rays following the decay of a t(1/2) = 3 μs isomer were observed, allowing one to establish the low-lying structure of Bi-217. The level energies and the reduced electric quadrupole transition probability B(E2) from the isomeric state are compared to large-scale shell-model calculations.
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AGATA Collaboration(Sahin, E. et al), Gadea, A., & Huyuk, T. (2015). Shell evolution beyond N=40: Cu-69,Cu-71,Cu-73. Phys. Rev. C, 91(3), 034302–9pp.
Abstract: The level structure of the neutron-rich Cu-69, Cu-71, and Cu-73 isotopes has been investigated by means of multinucleon transfer reactions. The experiment was performed at Laboratori Nazionali di Legnaro using the AGATA Demonstrator array coupled to the PRISMA magnetic spectrometer. Lifetimes of excited states in Cu nuclei were measured with the recoil-distance Doppler-shift method. The resulting electromagnetic matrix elements for transitions from excited states in Cu-69,Cu-71,Cu-73 nuclei are used to assess the collective or single-particle character of these states. The results are compared with predictions of large-scale shell-model calculations, giving further insight into the evolution of the proton pf shell as neutrons fill the 1g(9/2) orbital.
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