Lifetimes of low-lying excited states of the neutron-rich ${}^{44,46}\mathrm{Ar}$ 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 $B$($E2;2^{+}\to 0^{+}$) transition probability from ${}^{44}\mathrm{Ar}$ to the closed-shell nucleus ${}^{46}\mathrm{Ar}$ contradicts the earlier results of Coulomb-excitation experiments. Shell-model calculations using different effective interactions agree with the new measured values.

• Received 21 April 2010

DOI:https://doi.org/10.1103/PhysRevC.82.024308