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Vincent Maquet

Publications and source records attributed to Vincent Maquet.

2 recordsLinked to original sources

Towards solving the ICRH wave and Fokker-Planck equations self-consistently

The present paper sketches a framework for solving the wave and Fokker-Planck equations in the ion cyclotron resonance frequency domain fully selfconsistently. It illustrates this can be done by first constructing "building blocks" that are commonly needed by the wave and Fokker-Planck equations, allowing e.g. to account for wave coupling in plasmas containing non-Maxwellian distributions. Up to details, the paper exploits known expressions and methods to solve the two intimately connected aspects of the description of the wave-particle interaction underlying ion cyclotron resonance heating. Two cases are presented: the case where the guiding centre motion is limited to just following magnetic field lines, and the extended case accounting for drifts away from magnetic surfaces but assuming axisymmetry. A limited set of analytical results is included. As combining wave and Fokker-Planck solving is the focus, the computation of the dielectric response for arbitrary distribution functions is illustrated as well.

physics.plasm-ph

Analytical edge power loss at the lower hybrid resonance: comparison with ANTITER IV and application to ICRH systems

In non-inverted heating scenarios, a lower hybrid (LH) resonance can appear in the plasma edge of tokamaks. This resonance can lead to large edge power deposition when heating in the ion cyclotron resonance frequency (ICRF) range. In this paper, the edge power loss associated with this LH resonance is analytically computed for a cold plasma description using an asymptotic approach and analytical continuation. This power loss can be directly linked to the local radial electric field and is then compared to the corresponding power loss computed with the semi-analytical code ANTITER IV. This method offers the possibility to check the precision of the numerical integration made in ANTITER IV and gives insights in the physics underlying the edge power absorption. Finally, solutions to minimize this edge power absorption are investigated and applied to the case of ITER's ion cyclotron resonance heating (ICRH) launcher. This study is also of direct relevance to DEMO.

physics.plasm-ph