학술논문

Evidence of oblate-prolate shape coexistence in the strongly-deformed nucleus 119Cs
Document Type
article
Source
Physics Letters B, Vol 822, Iss , Pp 136645- (2021)
Subject
Nuclear reaction:58Ni(64Zn,3p)119Cs
Measured γγγ-coincidences
Angular correlations
Linear polarization
Model calculation
Oblate-prolate coexistence
Physics
QC1-999
Language
English
ISSN
0370-2693
Abstract
Prolate-oblate shape coexistence close to the ground state in the strongly-deformed proton-rich A≈120 nuclei is reported for the first time. One of the four reported bands in 119Cs, built on a 11/2− state at 670 keV, consists of nearly degenerate signature partners, and has properties which unequivocally indicate the strongly-coupled πh11/2[505]11/2− configuration associated with oblate shape. Together with the decoupled πh11/2[541]3/2− band built on the 11/2− prolate state at 110 keV, for which a half-life of T1/2=55(5)μs has been measured, the new bands bring evidence of shape coexistence at low spin in the proton-rich strongly deformed A≈120 nuclei, a phenomenon predicted since long time, but not yet observed. Calculations using the particle-number conserving cranked shell model and two dimensional tilted axis cranking covariant density functional theory support and well reproduce the observed oblate and prolate coexisting low-energy states in 119Cs.