While current tokamak experiments are beginning to use real-time feedback control systems to manage the plasma exhaust, future tokamaks still require validation of theoretical models used to predict the threshold impurity concentration required to sufficiently reduce the power and particle fluxes to the divertor. This work exploits new spectroscopic measurements of the divertor nitrogen concentration, $c_N$, in partially detached N₂-seeded H-mode plasmas on ASDEX Upgrade (AUG) and JET with the ITER-Like Wall (JET-ILW) to test the parameter dependencies of the power flowing to the outer divertor, $P_{\mathit{div},\mathit{outer}}$, and the separatrix electron density, $n_{e,\mathit{sep}}$. A least-squares regression of the AUG measurements demonstrates that the threshold $c_N$ required for detachment scales as $c_N\propto P_{\mathit{div},\mathit{outer}}^{1.19\pm 0.32}{n}_{e,\mathit{sep}}^{-2.77\pm 0.36}$. This scaling of $n_{e,\mathit{sep}}$ is also consistent with the measurements from JET which, at constant $P_{\mathit{div},\mathit{outer}}$, show $c_N\propto n_{e,\mathit{sep}}^{-2.43\pm 0.27}$. The dependencies of $P_{\mathit{div},\mathit{outer}}$ and $n_{e,\mathit{sep}}$ is demonstrated over at least a factor of two change in both parameters and indicates a stronger dependence on $n_{e,\mathit{sep}}$ in comparison to the Lengyel model, which could be due to the assumption in this model that the heat flux channel width is independent of density. This first assessment of detachment scaling with impurity seeding highlights the need for further analysis of the systematic uncertainties of the measurement and more consistent scenarios from more tokamaks to investigate the machine size scaling.

虽然当前的托卡马克实验开始使用实时反馈控制系统来管理等离子体排放，但未来的托卡马克仍需要验证理论模型，用于预测充分降低到偏滤器的功率和粒子通量所需的阈值杂质浓度。这项工作利用了偏滤器氮浓度的新光谱测量，$C_N$，在ASDEX Upgrade (AUG) 和 JET 上部分分离的 N ₂种子 H 模式等离子体中，使用 ITER-Like Wall (JET-ILW) 来测试流向外部偏滤器的功率的参数依赖性，${磷}_{\mathit{div},\mathit{外}}$，和分界线电子密度， $n_{\mathrm{电子},\mathit{九月}}$. AUG 测量值的最小二乘回归表明阈值$C_N$ 分离尺度要求为 $C_N\propto {磷}_{\mathit{div},\mathit{外}}^{1.19\pm 0.32}{n}_{\mathrm{电子},\mathit{九月}}^{——2.77\pm 0.36}$. 这种缩放$n_{\mathrm{电子},\mathit{九月}}$ 也与来自 JET 的测量结果一致，在恒定 ${磷}_{\mathit{div},\mathit{外}}$， 表演 $C_N\propto n_{\mathrm{电子},\mathit{九月}}^{——2.43\pm 0.27}$. 的依赖关系${磷}_{\mathit{div},\mathit{外}}$ 和 $n_{\mathrm{电子},\mathit{九月}}$ 至少在两个参数的两倍变化中得到证明，并表明对 $n_{\mathrm{电子},\mathit{九月}}$与 Lengyel 模型相比，这可能是由于该模型中假设热通量通道宽度与密度无关。这是对带有杂质种子的脱屑结垢的首次评估，强调了需要对测量的系统不确定性和来自更多托卡马克的更一致方案进行进一步分析以研究机器尺寸结垢的需求。