Sensitivity of Fusion Plasma Temperature Profiles to Localized and Distributed Heat Sources

The evolution of fusion plasma temperature profiles in the presence of spatially localized or distributed sources is investigated with particular emphasis on Electron Cyclotron Heating. A central expansion technique is used, for which the time dependence of the expansion parameters (amplitude, width and shape) are found to be sensitive to the width of the temperature source and to the position of the boundary. The results obtained are in qualitative agreement with recent experiments on Electron Cyclotron heating.