Lifetime measurements in 98Ru using inverse Coulomb excitation and Recoil Distance Doppler Shift Method

Controversial publications can be found about the vibrational character of 98Ru. With big uncertainties in essential quantities like the B4/2 value, the ratio between the 4+1→ 2+1 and the 2+1→ 0+1 E2 transition strengths, theoretical interpretations are difficult. In order to reduce uncertainties, the Recoil Distance Doppler Shift method was used to measure the lifetimes of the 2+1,2 and 4+1 states. This technique, combined with inverse Coulomb excitation as an excitation mechanism, yields high precision lifetimes. Due to the high v/c several corrections due to relativistic and deorientation effects are required. Both, results and corrections will be discussed, with emphasis on the simultaneous measurement of lifetime and deorientation. The new results on the absolute transition strengths are compared to different theoretic predictions and data on other nuclei in the mass region.