Structure of $^{240}$Pu: Evidence for Octupole Phonon Condensation?
nucl-ex
/ Authors
X. Wang, R. V. F. Janssens, M. P. Carpenter, S. Zhu, I. Wiedenhöver, U. Garg, S. Frauendorf, T. Nakatsukasa, I. Ahmad, A. Bernstein
and 12 more authors
E. Diffenderfer, S. J. Freeman, J. P. Greene, T. L. Khoo, F. G. Kondev, A. Larabee, T. Lauritsen, C. J. Lister, B. Meredith, D. Seweryniak, C. Teal, P. Wilson
/ Abstract
The expanded level structure of $^{240}$Pu available from the present study highlights the role of strong octupole correlations in this nucleus. Besides a delayed alignment in the yrast band, the observations include the presence of both $I^{+}{\to}(I-1)^{-}$ and $I^{-}{\to}(I-1)^{+}$ E1 transitions linking states of the yrast and negative-parity bands at high spin and the presence of an additional even-spin, positive-parity band deexciting exclusively to the negative parity sequence. The observations appear to be consistent with expectations based on the recently proposed concept of octupole phonon condensation.