A 5-1/2-dimensional theory for fast and accurate evaluation of the cyclotron resonance heating using a real-space wave representation

Abstract

The cyclotron resonance heating rate in a plasma has been evaluated so far from a five-dimensional (5D) quasilinear model because the 6D evaluation is prohibitively expensive. However, the quasilinear approach as applied to the cyclotron resonance heating has fundamental difficulties in evaluating the net effect from a large number of coupled wave modes (leading to strong spatial wave inhomogeneity) since the theory is built on the Fourier space wave representation, and does not include the regular nonlinear particle dynamics within a resonance passing event since the theory is based on the unperturbed orbit theory. A new 5-1/2D theory is formulated for evaluation of a more accurate resonant particle dynamics using the real-space wave representation, which overcomes the shortcomings of the quasilinear cyclotron resonance heating theories by reproducing the 6D physics at the 5D computing speed.