Spin-dependent evolution of collectivity in ${}^{112}\mathrm{Te}$

The evolution of collectivity with spin along the yrast line in the neutron-deficient nucleus ${}^{112}\mathrm{Te}$ has been studied by measuring the reduced transition probability of excited states in the yrast band. In particular, the lifetimes of the $4^{+}$ and $6^{+}$ excited states have been determined by using the recoil distance Doppler-shift method. The results are discussed using both large-scale shell-model and total Routhian surface calculations.

Figure 1

Spectra obtained after gating on the ${18}^{+}\to {16}^{+}$ transition at 957 keV in ${}^{112}\mathrm{Te}$ on a $\gamma \gamma$-coincidence matrix for several distances on the sensitivity region where the evolution of the $4^{+}\to 2^{+}$ (red lines) and the $6^{+}\to 4^{+}$ (blue lines) transitions at 787 and 821 keV, respectively, can be observed. Dashed and continuous lines represent the components emitted before and after the degrader, respectively.

Figure 2

Normalized intensities of the before and after degrader components (blue and red, respectively) of the $\gamma$ rays depopulating the $6^{+}$ excited state, as a function of the distance. The inner panel shows the lifetime value obtained in the present measurement by combining values for three distances in the sensitive region.

Figure 3

Top: Experimental values (right and left triangles for ${}^{112}\mathrm{Te}$ and ${}^{114}\mathrm{Te}$, respectively) and shell-model calculations for the energies (plus and star for ${}^{112}\mathrm{Te}$ and ${}^{114}\mathrm{Te}$, respectively) as a function of spin in the yrast band of ${}^{112}\mathrm{Te}$ and ${}^{114}\mathrm{Te}$. Bottom: Experimental values of the reduced transition probabilities as a function of spin for ${}^{112}\mathrm{Te}$ and ${}^{114}\mathrm{Te}$ in circles and squares, respectively. The values for ${}^{114}\mathrm{Te}$ have been taken from [8] while ${}^{112}\mathrm{Te}$ comes from [6] and from the present work. The up and down triangles correspond to the results obtained with the shell-model calculations from [10]. See text for details.

Figure 4

Potential-energy surface calculations performed with the Woods-Saxon parameters defined in Ref. [26] for (a) ${}^{112}\mathrm{Te}$ and (b) ${}^{114}\mathrm{Te}$. The black points correspond to the ground-state deformation minimum.