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arXiv · 2411.19004

On Density Limit of Lower Hybrid Current Drive caused by Parametric Decay Instability in Tokamak Plasmas

Kunyu Chen·Zhihao Su·Zikai Huang·Long Zeng·Zhe Gao
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Abstract

The density limit of lower hybrid current drive (LHCD) is scaled by coupling the saturation process of parametric decay instability induced by LH waves in the scrape off layer (SOL) plasma to the propagation of waves. It is shown that the density limit of LHCD satisfies $n_\text{lim}\propto L_y^{2/3} P_0^{-2/3}\omega_0^{2}B_0^{2/3}T_e$, which is consistent with results of simulations and previous experiments. Both theoretical analysis and simulation results indicate that the density limit is far from being reached for ITER baseline profile. Therefore, the density limit phenomena will not prevent LHCD from being a promising method of driving plasma current at ITER and future tokamaks.

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Kunyu Chen, Zhihao Su, Zikai Huang, Long Zeng, Zhe Gao. 2024-11-28. On Density Limit of Lower Hybrid Current Drive caused by Parametric Decay Instability in Tokamak Plasmas. https://arxiv.org/abs/2411.19004

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