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The vibrational first $2^+$ and $3^-$ states of the doubly-magic nucleus $^{132}$Sn were excited via safe Coulomb excitation (CE) employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The $^{132}$Sn ions were accelerated to an energy of 5.5 MeV/nucleon and impinged on a $^{206}$Pb target. Dexciting $\gamma$ rays from the first excited states of the target and the projectile nucleus were recorded in coincidence with scattered particles. The optimized beam energy, the high-energy resolution and good efficiency of the HPGe spectrometer provide a favourable combination to master the demanding measurement characterized by small CE cross sections of the high lying states with excitation energies above 4 MeV. The reduced transition strengths were determined for the transitions $0^+ \rightarrow 2^+_1$, $0^+ \rightarrow 3^-_1$, and $2^+_1 \rightarrow 3^-_1$ in $^{132}$Sn. In the past first preliminary results for the $B(E2; 0^+ \rightarrow 2^+_1)$ value were obtained with an efficient BaF2 array at ORNL [1]. The results on excited collective states in $^{132}$Sn provide crucial information on cross shell configurations that are expected to be dominated by a strong proton contribution. Large-scale shell model calculations and new mean field calculations are on its way.
[1] R.L. Varner, et al.; Eur. Phys. J. A 25, s01, 391 (2005)
