On the DSAM and lifetime measurements for superdeformed states

Some important results relating to the Doppler-shift-attenuation method are presented. We derive a new formalism equivalent to the Bateman equations which allows simple recursion relations to be developed for a cascade of γ-decays. The new formalism also requires properties which are experimentally reasonably accessible. Of particular importance are velocity distributions and we show how the lifetimes may be determined using their mean values. The results are shown to be independent of most sources of shift and width in these distributions. We discuss the conditions under which the widths may be related to intrinsic properties of the states. Other sources of width are discussed. Our method is illustrated with applications relevant to the superdeformed bands in 152Dy and 133Nd. (Author)