Excited level lifetime measurements following very low energy nuclear recoils

Using high resolution gamma spectroscopy it is possible to observe Doppler broadening of gamma transitions from excited states which have themselves been populated after emission of gamma photons or other low energy nuclear radiation. This allows the determination of the lifetimes of these intermediate states, providing the time dependence of the recoil velocities is known. Conversely, if the lifetime is well known, this technique may be used to study the recoil process itself (and hence the atomic interaction) at energies of only a few times the lattice binding energy.