9413046 Bellan This proposal calls for an investigation of the linkage between orbit stochasticity, a microscopic effect, and macroscopic properties of the plasma. In particular the investigator will look for a flattening of the distribution function and a reduction of fluid response to the drift wave in the plasma. The technique used will involve laser induced fluorescence. In a more sophisticated application of the fluorescence technique, optical tagging will be used to allow tracking the trajectories of specific subgroups of ions.