The influence of passive edge emission on the charge exchange (CX) spectra of carbon (C5+, n = 8 → 7 at 529 nm) measured in fusion plasmas at the ASDEX Upgrade tokamak is investigated. The spectra are obtained viewing the plasma edge tangentially with eight lines of sight while the plasma is swept to enhance the spatial density of the measurements. A forward model to deconvolute the measured line-integrals is employed. The local emissions are then compared with the simulated radiation obtained with the 1D impurity transport code STRAHL using transport coefficients which are determined independently. Depending on the background neutral deuterium densities the simulation predicts the absolute line intensities and the relative contributions of electron impact excitation and thermal CX to the measured signals. Therefore, a background neutral deuterium density profile has been determined. For the passive emission line of C5+, the comparison between forward model and simulations yields that electron impact excitation and thermal CX are both important for understanding the passive line. Indeed, thermal CX proves to be affecting the passive emission line considerably via two mechanisms, i.e. change in the ionization equilibrium through CX recombination and radiation due to local CX reactions.
受控聚变等离子体中碳（C5+，n = 8 → 7，529 nm）电荷交换（CX）光谱的被动边缘发射研究，是在ASDEX Upgrade托卡马克装置上进行的。通过八条视线切向观测等离子体边缘，并在扫描等离子体以增强空间密度测量的条件下获取光谱。采用正演模型对测量的线积分信号进行反卷积，得到局部发射率，并将其与使用独立确定的输运系数的一维杂质输运代码STRAHL模拟的辐射进行比较。模拟结果表明，根据背景中性氘密度的大小，预测的绝对谱线强度以及电子碰撞激发和热CX对测量信号的相对贡献会有所不同。因此，确定了背景中性氘密度剖面。对于C5+的被动发射线，正演模型与模拟的比较表明，电子碰撞激发和热CX对理解该被动谱线均很重要。实际上，热CX通过两种机制显著影响被动发射线：一是通过CX复合改变电离平衡，二是通过局部CX反应产生辐射。