The generalized centroid shift method for lifetime measurements in heavy ion reactions

Abstract

An application of the generalized centroid shift method for lifetime measurements in the nano-second and subnanosecond region in HI reactions on the Rutgers tandem is described. Depayed γγ-coincidence measurements using plastic scintillators (start) and a germanium detector (stop) are discussed. Details of the analysis including treatment of the time background (random coincidences) and the choice of range of analysis of the time distributions are considered. As illustrations, lifetime measurements performed in (HI, xp yn) reactions are presented: T 1 2 (3679 keV in 106 Cd)=0.7±0.2 ns , T 1 2 (3508 keV in 106 Cd)=1.2±0.4 ns , T 1 2 (1256 keV in 109 Sn)=2.0±0.3 ns and T 1 2 (3177 keV in 100 Pd)=0.9±0.2 ns .