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Competition of Oblate and Prolate Deformation in 3469,70,71,72Se

  • T. Mylaeus
  • J. Busch
  • P. von Brentano
  • J. Eberth
  • M. Liebchen
  • N. Schmal
  • R. Sefzig
  • S. Skoda
  • W. Teichert
  • M. Wiosna
  • W. Nazarewicz
Conference paper
Part of the Research Reports in Physics book series (RESREPORTS)

Abstract

In the course of our systematic nuclear structure investigations of the A≈70 mass region, our special interest focused on the light Se isotopes, which are very good examples for shape coexistence phenomena at low spins. In these nuclei, the ground state rotational band is crossed at I≈4–6 by a more deformed configuration [1,2]. Due to the large band interaction (of the order of a few hundred keV) both bands are strongly mixed in the 0+, 2+ and 4+ states. Calculations employing the deformed shell model and the shell correction procedure explain shape coexistence with two minima in the potential energy surface, one at small oblate, the other at large prolate deformation [3]. A rotational band built on the excited 0 2 + state was known since long up to spin 10+ in 72Se (see e.g. the contribution of R.Bengtsson in this book). The microscopic reason for the prolate oblate shape coexistence in Se isotopes can be easily understood from the single particle Nilsson diagram (see e.g. refs [3,4]). The large (about 1.5 MeV) Z=34 gaps appear both at prolate and oblate shapes, at N = 38 the gap opens at large prolate shapes while oblate configurations in Se are stabilized by the N = 36 shell gap.

Keywords

Rotational Band Neutron Multiplicity Reaction 40Ca Oblate Shape Yrast Band 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • T. Mylaeus
    • 1
  • J. Busch
    • 1
  • P. von Brentano
    • 1
  • J. Eberth
    • 1
  • M. Liebchen
    • 1
  • N. Schmal
    • 1
  • R. Sefzig
    • 1
  • S. Skoda
    • 1
  • W. Teichert
    • 1
  • M. Wiosna
    • 1
  • W. Nazarewicz
    • 2
  1. 1.Institut für KernphysikUniversität zu KölnKöln 41Fed. Rep. of Germany
  2. 2.Institute of PhysicsWarsaw Institute of TechnologyWarsawPoland

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