Lifetime Measurements—A Powerful Tool to Study Nuclear Structure

Advanced Doppler-shift methods for the calculation of the γ-ray lineshape registered in recoil-distance Doppler-shift and Doppler-shift attenuation methods are presented, emphasizing the case using a gate set on the shifted part of a direct feeding transition. For the precise description of the γ-ray lineshape, the process of evaporation of light particles from the compound nucleus has to be taken into account in the case of heavy ion-induced fusion-evaporation reactions. In addition, the impact of different approaches for calculating stopping powers is investigated in the process of the lifetime determinations. In the RDDS experiments, the γ-emission during the slowing down in the stopper is discussed in detail. Applications of the new procedures are demonstrated in two experiments: the first one is a plunger experiment performed in order to check for chirality in the 134Pr nucleus and the second one is a DSAM experiment conducted to test the isospin symmetry in 31P and 31S mirror nuclei.