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Rapid shape evolutions near A = 100 are now the focus of much attention in nuclear science. Much of the recent work has been centered on isotopes with Z

A semi-thick target method has been used to measure the stopping power for recoils produced in the 120 Sn( 14 N, 5n) 129 La, 120 Sn( 11 B, 4n) 127 Cs and 118 Sn( 11 B, 4n) 125 Cs reactions by γ-ray lineshape analysis. The target quality and thickness (1.2 mg/cm 2 ) were determined by the Rutherford backscattering spectrometry technique. Electronic and nuclear stopping-power parameters were determined for Cs and La ions in Sn and compared with parameters measured with the same method for Pm, Sm and Nd ions in Cd and I ions in Ag. A comparison with the LSS theory was made for the energy range below 0.2 MeV/nucleon, where the Bethe–Bloch formula has no application.

Swedish Research Council; European Community [HPRI-CT 1999-00019]; Spanish MINECO [FPA2015-65035-P]

gamma-ray and fast-timing spectroscopy were used to study levels in Al-30 populated following the beta(-) decay of Mg-30. Five new transitions and three new levels were located in Al-30. A search was made to identify the third 1(+) state expected at an excitation energy of similar to 2.5 MeV. Two new levels were found, at 3163.9 and 3362.5 keV, that are firm candidates for this state. Using the advanced time-delayed (ATD) beta gamma gamma (t) method we have measured the lifetime of the 243.8-keV state to be T-1/2 = 15(4) ps, which implies that the 243.8-keV transition is mainly of M1 character. Its fast B(M1; 2(+) -> 3(+)) value of 0.10(3) W.u. is in very good agreement with the USD shell-model prediction of 0.090 W.u. The 1801.5-keV level is the only level observed in this study that could be a candidate for the second excited 2(+) state.

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10 pags.; 6 figs.; 4 tabs. ; Open Access funded by Creative Commons Atribution Licence 4.0, We have applied the fast timing β(t) technique to remeasure lifetimes of selected states in Ra populated in the β decay of Fr. T = 587(12) ps and 210(13)ps have been obtained for the 3/2 and 5/2 states at 50.1 and 79.7 keV, that are more accurate than the previous values of 630(70)ps and 166(55)ps, respectively. Our |D| value of 0.155(10) e·fm obtained for the K=3/2 configuration together with the available values of |D| for the K=1/2 and K=5/2 parity doublet bands establish the configuration dependence of |D| at low spins in this nucleus. Results of theoretical calculations performed for Ra, using the quasiparticle-phonon model (QPM) with inclusion of the Coriolis coupling, reasonably well reproduce octupole correlations in this nucleus. © The Author(s), 2016, This work was supported in part by the Swedish Natural Science Research Council, Norwegian Scientific Research Committee, the Nansen Foundation, the CICYT “Plan Nacional de Altas Energias” Spain (under contract AEN94-0833-C02-02), the U.K. Engineering and Physical Sciences Research Council, and the Polish Scientific Research Committee.

Several new subnanosecond lifetimes were measured in Pd-109 using the fast-timing beta gamma gamma (t) method. Fission fragments of the A = 109 mass chain were produced by bombarding natural uranium with 30 MeV protons at the Jyvaskyla Ion Guide Isotope Separator On-Line (IGISOL) facility. Lifetimes were obtained for excited states in Pd-109 populated following beta decay of Rh-109. The new lifetimes provide some insight into the evolution of nuclear structure in this mass region. In particular, the distinct structure of the two low-lying 7/2(+) states occurring systematically across the Pd isotopic chain is supported by the new lifetime measurements. The available nuclear data indicate a sudden increase in deformation at N = 60 which is related to the strong p-n interaction between pi g(9/2) and vg(7/2) valence nucleons expected in this region.

Properties of excited states in Nd-147 have been studied with the multispectra and gamma gamma coincidencemeasurements. Twenty-four new gamma lines and three new levels have been introduced into the level scheme of Nd-147. Using the advanced time-delayed beta gamma gamma(t) method, we measured lifetimes of eight excited levels in Nd-147, populated via the beta decay of Pr-147. We have determined reduced transition probabilities for 30 gamma transitions. Multidimensional potential energy surface calculations performed for Nd-147 suggest two single-quasiparticle configurations with nonzero octupole deformation, with K = 1/2 and K = 5/2. Our calculations also predict a sizable value of the electric dipole moment vertical bar D-0 vertical bar = 0.26e fm for this nucleus, while experimentally, a lower limit of vertical bar D-0 vertical bar >= 0.02e fm has been evaluated for the supposed K = 1/2 parity doublet. In contrast to the theoretical results, we do not observe the parity doublet bands with K = 5/2. This, and the lack of theoretically expected E1 strength in Nd-147,Nd-149 may signal some poorly understood structural effect in the odd-N lanthanides.