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arXiv · 1406.3814

Phase change near $N=70$ in the wave function of the $I^π=11/2^-$ isomers along the cadmium-isotope chain

Y. Lei·H. Jiang·S. Pittel
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Abstract

The electromagnetic features of the $11/2^-$ isomers in the $^{111-127}$Cd isotopes are reproduced by numerically optimized shell-model wave-functions. A sudden phase change of the wave functions at $N = 70$ is identified and further confirmed by the evolution of B(E2, $7/2^-_1\rightarrow 11/2^-_1$) values. This phase change gives rise to different linear relations for the $Q$ and $μ$ values with $N<70$ and $N>70$, as needed to reproduce the experimental data. The particle-hole transformation properties for $h_{11/2}$ neutrons in a well-isolated subshell involving degenerate $s_{1/2}$, $d_{3/2}$, $d_{5/2}$ and $h_{11/2}$ orbits is suggested as a possible explanation for this phase change.

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Y. Lei, H. Jiang, S. Pittel. 2015-08-24. Phase change near $N=70$ in the wave function of the $I^π=11/2^-$ isomers along the cadmium-isotope chain. https://doi.org/10.1103/physrevc.92.024321

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