1. High-Spin States in the Transitional Palladium Nuclei Observed in Heavy-Ion Induced Fission
- Author
-
E. Gueorguieva, N. Schulz, T. Kutsarova, P. Petkow, H. Sergolle, M. G. Porquet, Josette Duprat, Anna Wilson, S. Bouneau, R. Lucas, A. Minkova, F. Hoellinger, I. Deloncle, C. Bourgeois, B. J. P. Gall, Ts. Venkova, C. Gautherin, F. Azaiez, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), and Smit F.D. Lindsay R. Foertsch S.V.
- Subjects
Physics ,Spin states ,010308 nuclear & particles physics ,Fission ,Nuclear Theory ,Radiochemistry ,Gamma ray ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,01 natural sciences ,Molecular physics ,Spectral line ,0103 physical sciences ,Potential energy surface ,Quasiparticle ,Nuclear fusion ,Nuclear Experiment ,010306 general physics ,Spontaneous fission - Abstract
The low-spin collective excitations of even-even Pd nuclei in the A ≈ 110 mass region indicate a structural transition from an anharmonic vibrator to a gamma-soft rotor. This observation is supported by recent calculations of the potential energy surfaces using different types of mean field approaches. In particular, prolate-to-oblate shape transition has been predicted at 111Pd [1]. Experimental evidence for a shape change or shape coexistence can be obtained by high-spin studies of these transitional nuclei. Band crossings in the odd-N Pd nuclei are especially important to understand the origin of the alignments. No band structures built on the low-lying states were known in heavier odd Pd nuclei (A≥109). High-spin states in these nuclei cannot be populated using fusion-evaporation reactions. The heavier neutron-rich 112,114,116Pd nuclei have been studied from spontaneous fission of 252Cf [2]. In this work the less neutron-rich Pd nuclei have been produced as fission fragments following the fusion reactions 28Si + 176Yb at 145 MeV. The 28Si beam was provided by the Vivitron accelerator in Strasbourg. Gamma rays were recorded with the EUROGAM2 array [3]. The level schemes were constructed by examining γ- spectra extracted from two and three dimensional matrices.
- Published
- 2000
- Full Text
- View/download PDF