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The lifetimes of the first excited states of the N = 30 isotones (50)Ca and (51)Sc have been determined using the Recoil Distance Doppler Shift method in combination with the CLARA-PRISMA spectrometers. This is the first time such a method is applied to measure lifetimes of neutron-rich nuclei populated via a multinucleon transfer reaction. This extends the lifetime knowledge beyond the f_{7/2} shell closure and allows us to derive the effective proton and neutron charges in the fp shell near the doubly magic nucleus (48)Ca, using large-scale, shell-model calculations. These results indicate an orbital dependence of the core polarization along the fp shell.

Lifetimes of low-lying excited states of the neutron-rich 44,46 Ar nuclei, populated via multinucleon transfer reactions, are measured by means of the differential recoil distance Doppler shift method. The extracted electromagnetic transition probabilities are compared with previous intermediate-energy Coulomb-excitation measurements and with large-scale shell-model calculations. The increase in the deduced B(E2; 2 + → 0 +) transition probability from 44 Ar to the closed-shell nucleus 46 Ar contradicts the earlier results of Coulomb-excitation experiments. Shell-model calculations using different effective interactions agree with the new measured values.

Lifetime measurements have been made in the neutron-deficient nucleus 109 Te using the coincident recoil distance Doppler-shift method. The experimental B(E2) values have been compared with state-of-the-art shellmodel calculations using the monopole-corrected realistic charge-dependent Bonn nucleon-nucleon potential. Lifetimes in the νh 11/2 band are consistent with an interpretation based on the deformation driving properties of a single valence neutron outside of the even-even tellurium core and highlight the unexpected presence of collective behavior as the N = 50 shell closure is approached. Lifetime measurements for the low-lying positive-parity states also appear to correlate well with shell-model calculations. In addition, a comparison with the proton-unbound nucleus 109 I suggests that the presence of a single decoupled valence proton affects the total measured B(E2) strengths in a manner that is not currently well understood.

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