Implementation of the Doppler Shift Attenuation Method Using TIP/TIGRESS at TRIUMF: Fusion-evaporation Lifetime Measurements in 22Ne

A method is presented for the determination of gamma-ray energies and transition rates in nuclei populated using the fusion-evaporation reaction mechanism and measured using the Doppler-shift attenuation method (DSAM). This method is applied to data collected for the stable benchmark nucleus 22Ne during a commissioning experiment at TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, employing a 12C(18O,2α)22Ne fusion-evaporation reaction. Gamma-ray energies were determined using offline reconstruction to correct for the Doppler shift. Mean lifetimes of the corresponding transitions were then measured via a comparison to Monte-Carlo lineshape simulations developed using the GEANT4 framework. Best fit lifetimes obtained using χ2 analysis were in general agreement with the existing literature, validating the analysis method used.