Coexistence of Reflection Asymmetric and Symmetric Shapes in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>Ba</mml:mi></mml:mrow><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>144</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math>
Shiwei Zhu, E. H. Wang, J. H. Hamilton, A. V. Ramayya, Y. X. Liu, N. T. Brewer, Y. X. Luo, J. O. Rasmussen, Zhigang Xiao, Y. Huang, G. M. Ter–Akopian, Ts.Yu. Oganessian
Abstract
Level structures in the neutron-rich ^{144}Ba nucleus have been reinvestigated by measuring prompt γ rays in the spontaneous fission of ^{252}Cf. The previous s=+1 octupole band structure with reflection asymmetric shape has been expanded, and a side quadrupole band structure based on a 3^{+} state with reflection symmetric shape is identified. Thus, the results show the coexistence of reflection asymmetric and symmetric shapes in ^{144}Ba. This is a first identification of such a shape coexistence structure in a nuclear structure. The other structural characteristics are discussed.