Although lower hybrid waves are effective at driving currents in present-daytokamaks, they are expected to interact strongly with high-energy particles inextrapolating to reactors. In the presence of a radial alpha particle birthgradient, this interaction can take the form of wave amplification rather thandamping. While it is known that this amplification more easily occurs whenlaunching from the tokamak high-field side, the extent of this amplificationhas not been made quantitative. Here, by tracing rays launched from the high-field-side of a tokamak, the required radial gradients to achieve amplificationare calculated for a temperature and density regime consistent with ahot-ion-mode fusion reactor. These simulations, while valid only in the linearregime of wave amplification, nonetheless illustrate the possibilities for waveamplification using high-field launch of the lower hybrid wave.
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