Dijon, A. et al, Gadea, A., & Huyuk, T. (2012). Discovery of a new isomeric state in Ni-68: Evidence for a highly deformed proton intruder state. Phys. Rev. C, 85(3), 031301–5pp.
Abstract: We report on the observation of a new isomeric state in Ni-68. We suggest that the newly observed state at 168(1) keV above the first 2(+) state is a pi(2p-2h) 0(+) state across the major Z = 28 shell gap. Comparison with theoretical calculations indicates a pure proton intruder configuration and the deduced low-lying structure of this key nucleus suggests a possible shape coexistence scenario involving a highly deformed state.
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de Angelis, G. et al, & Gadea, A. (2012). Shape isomerism and shape coexistence effects on the Coulomb energy differences in the N = Z nucleus As-66 and neighboring T=1 multiplets. Phys. Rev. C, 85(3), 034320–7pp.
Abstract: Excited states of the N = Z = 33 nucleus As-66 have been populated in a fusion-evaporation reaction and studied using gamma-ray spectroscopic techniques. Special emphasis was put into the search for candidates for the T = 1 states. A new 3(+) isomer has been observed with a lifetime of 1.1(3) ns. This is believed to be the predicted oblate shape isomer. The excited levels are discussed in terms of the shell model and of the complex excited Vampir approaches. Coulomb energy differences are determined from the comparison of the T = 1 states with their analog partners. The unusual behavior of the Coulomb energy differences in the A = 70 mass region is explained through different shape components (oblate and prolate) within the members of the same isospin multiplets. This breaking of the isospin symmetry is attributed to the correlations induced by the Coulomb interaction.
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Marginean, R., Rusu, C., Marginean, N., Bucurescu, D., Ur, C. A., de Angelis, G., et al. (2012). High-spin structure of Pd-95. Phys. Rev. C, 86(3), 034339–9pp.
Abstract: The level scheme of the neutron-deficient nucleus Pd-95 has been studied with the Ni-58 + Ca-40 fusion-evaporation reaction at 135 MeV with the GASP gamma-ray array, the ISIS silicon ball, and the N-ring neutron detector. Excited levels with spins at least up to 45/2 (h) over bar are reported for both parities. The observed experimental data are compared to large-scale shell-model calculations.
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Szilner, S. et al, & Gadea, A. (2013). Transfer Reaction Studies with Spectrometers. Acta Phys. Pol. B, 44(3), 417–426.
Abstract: The revival of transfer reaction studies benefited from the construction of the new generation large solid angle spectrometers, coupled to large gamma arrays. The recent results of gamma-particle coincident measurements in Ca-40+Zr-96 and Ar-40+Pb-208 reactions demonstrate a strong interplay between single-particle and collective degrees of freedom that is pertinent to the reaction dynamics. The development of collectivity has been followed in odd Ar isotopes populated in the Ar-40+Pb-208 reaction through the excitation of the 11/2(-) states, understood as the coupling of single particle degrees of freedom to nuclear vibration quanta. Pair transfer modes is another important degree of freedom which is presently being studied with Prisma in inverse kinematics at energies far below the Coulomb barrier. First results from the Zr-96+Ca-40 reaction elucidate the role played by nucleon-nucleon correlation.
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Bottoni, S., Benzoni, G., Leoni, S., Montanari, D., Bracco, A., Vigezzi, E., et al. (2013). Reaction dynamics and gamma spectroscopy of Ne isotoopes by the heavy ion reaction Ne-22+Pb-208. Acta Phys. Pol. B, 44(3), 457–461.
Abstract: The heavy ion reaction Ne-22+Pb-208 at 128 MeV beam energy has been studied using the PRISMA-CLARA experimental setup at Legnaro National Laboratories. Aim of the experiment is the measurement of elastic, inelastic and one nucleon transfer cross sections. The data are presented in parallel with similar results for the unstable Ne-24 nucleus, using existing data from the reaction Ne-24+Pb-208 at 182 MeV (measured at SPIRAL with the VAMOS-EXOGAM setup). A comparison with angular distributions obtained by semiclassical and DWBA predictions for the quadrupole deformation parameter is also discussed. In particular, the DWBA analysis allowed to determine the beta(C)(2) charge deformation parameter both in Ne-22 and Ne-24.
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