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arXiv · 1307.6319

Kinetic simulation of the O-X conversion process in dense magnetized plasmas

M Ali Asgarian·J P Verboncoeur·A Parvazian·R Trines
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Abstract

The ordinary-extraordinary-Bernstein (O-X-B) double conversion is considered and simulated with a kinetic particle model vs full wave model for parameters of the TJ-II stellarator. This simulation has been done with the particle-in-cell code, XOOPIC (X11-based object-oriented particle-incell). XOOPIC is able to model the non-monotonic density and magnetic profile of TJ-II. The first step of conversion, O-X conversion, is observed clearly. By applying some optimizations such as increasing the number of computational particles in the region of the X-B conversion, the simulation of the second step is also possible. By considering the electric and magnetic components of launched and reflected waves, the O-mode wave and the X-mode wave can be easily detected. Via considering the power of launched O-mode wave and converted X-mode wave, the efficiency of O-X conversion for the best theoretical launch angle is obtained, which is in good agreement with previous computed efficiencies via full-wave simulations. For the optimum angle of 47? between the wave-vector of the incident O-mode wave and the external magnetic field, the conversion efficiency is 66%.

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M Ali Asgarian, J P Verboncoeur, A Parvazian, R Trines. 2013-07-24. Kinetic simulation of the O-X conversion process in dense magnetized plasmas. https://doi.org/10.1063/1.4826977

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