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Anomalous Properties of Quadrupole Collective States in $^{136}$Te and beyond

Noritaka Shimizu·Takaharu Otsuka·Takahiro Mizusaki·Michio Honma
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Abstract

The ground and low-lying states of neutron-rich exotic Te and Sn isotopes are studied in terms of the nuclear shell model by the same Hamiltonian used for the spherical-deformed shape phase transition of Ba isotopes, without any adjustment. An anomalously small value is obtained for $B(E2;0^+_1\to 2^+_1)$ in $^{136}$Te, consistently with a recent experiment. The levels of $^{136}$Te up to yrast $12^+$ are shown to be in agreement with observed ones. It is pointed out that $^{136}$Te can be an exceptionally suitable case for studying mixed-symmetry 1$^+$, 2$^+$ and 3$^+$ states, and predictions are made for energies, M1 and E2 properties. Systematic trends of structure of heavier and more exotic Sn and Te isotopes beyond $^{136}$Te are studied by Monte Carlo Shell Model, presenting an unusual and very slow evolution of collectivity/deformation.

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Noritaka Shimizu, Takaharu Otsuka, Takahiro Mizusaki, Michio Honma. 2004-10-06. Anomalous Properties of Quadrupole Collective States in $^{136}$Te and beyond. https://doi.org/10.1103/physrevc.70.054313%2010.1103%2Fphysrevc.74.059903

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