The variation of pressure-gradient-driven turbulence with plasma $\beta$ (up to $\beta \approx 15\,\%$ ) is investigated in linear, magnetized plasma. The magnitude of magnetic fluctuations is observed to increase substantially with increasing $\beta$ . More importantly, parallel magnetic fluctuations are observed to dominate at higher $\beta$ values, with $\delta B_\parallel / \delta B_\perp \approx 2$ and $\delta B / B_0 \approx 1\,\%$ . Parallel magnetic fluctuations are strongly correlated with density fluctuations and the two are observed to be out of phase. The relative magnitude of and cross-phase between density and parallel magnetic field fluctuations are consistent with the dynamic pressure balance ( $P+{B_{0}^2}/{2\mu _0} = \textrm {constant}$ ). A local slab model theory for electromagnetic, modified drift Alfvén waves, including parallel magnetic fluctuations, shows partial agreement with experimental observations.

中文翻译：

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大型等离子体装置中增加的 β 等离子体中的电磁湍流

压力梯度驱动湍流随等离子体的变化 $\beta$ （取决于 $\beta \大约 15\,\%$ ) 在线性磁化等离子体中进行研究。观察到磁波动的幅度随着增加而显着增加 $\beta$ . 更重要的是，观察到平行磁波动在较高的 $\beta$ 值，与 $\delta B_\parallel / \delta B_\perp \大约 2$ 和 $\delta B / B_0 \大约 1\,\%$ . 平行磁波动与密度波动密切相关，并且观察到两者异相。密度和平行磁场波动之间的相对幅度和交叉相位与动态压力平衡一致（ $P+{B_{0}^2}/{2\mu _0} = \textrm {常数}$ ）。用于电磁修正漂移 Alfvén 波（包括平行磁波动）的局部平板模型理论显示与实验观察结果部分一致。