Onset of Collectivity in Neutron Deficient $^{196,198}$Po

L. A. Bernstein; J. A. Cizewski; H. -Q. Jin; W. Younes; R. G. Henry; L. P. Farris; A. Charos; M. P. Carpenter; R. V. F. Janssens; T. L. Khoo; T. Lauritsen; I. G. Bearden; D. Ye; J. A. Becker; E. A. Henry; M. J. Brinkman; J. R. Hughes; A. Kuhnert; T. F. Wang; M. A. Stoyer; R. M. Diamond; F. S. Stephens; M. A. Deleplanque; A. O. Macchiavelli; I. Y. Lee; B. Cederwall; J. R. B. Oliveira; J. Burde; P. Fallon; C. Duyar; J. E. Draper; E. Rubel; D. T. Vo

doi:10.1103/physrevc.52.621

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Onset of Collectivity in Neutron Deficient $^{196,198}$Po

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Abstract

We have studied via in-beam $γ$-ray spectroscopy $^{196}$Po and $^{198}$Po, which are the first neutron-deficient Po isotopes to exhibit a collective low-lying structure. The ratios of yrast state energies and the E2 branching ratios of transitions from non-yrast to yrast states are indicative of a low-lying vibrational structure. The onset of collective motion in these isotopes can be attributed to the opening of the neutron i$_{13/2}$ orbital at N$\approx$112 and the resulting large overlap between the two valence protons in the h$_{9/2}$ orbital and the valence neutrons in the i$_{13/2}$ orbital.

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L. A. Bernstein, J. A. Cizewski, H. -Q. Jin, W. Younes, R. G. Henry, L. P. Farris, A. Charos, M. P. Carpenter, R. V. F. Janssens, T. L. Khoo, T. Lauritsen, I. G. Bearden, D. Ye, J. A. Becker, E. A. Henry, M. J. Brinkman, J. R. Hughes, A. Kuhnert, T. F. Wang, M. A. Stoyer, R. M. Diamond, F. S. Stephens, M. A. Deleplanque, A. O. Macchiavelli, I. Y. Lee, B. Cederwall, J. R. B. Oliveira, J. Burde, P. Fallon, C. Duyar, J. E. Draper, E. Rubel, D. T. Vo. 1995-07-13. Onset of Collectivity in Neutron Deficient $^{196,198}$Po. https://doi.org/10.1103/physrevc.52.621

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