Second Harmonic Cyclotron Heating of Sloshing Ions in a Straight Field Line Mirror

The second harmonic heating in mirrors is explicated. A new coordinate-independent form of the second harmonic term in the plasma dielectric response is derived. The second harmonic heating in the WKB limit is addressed and compared with minority heating. A newly developed three-dimensional model for the time-harmonic boundary problem for Maxwell's equations is used for second harmonic heating modeling in the reactor-scale straight field line mirror device. Computations show that the antenna Q is low and the regime of global resonance overlapping is in effect. Only a small portion of the wave energy transits through the cyclotron layer and penetrates to the central part of the trap. The power deposition is peaked at the plasma core.