For certain scattering geometries collective Thomson scattering (CTS) measurements are sensitive to the composition of magnetically confined fusion plasmas. CTS therefore holds the potential to become a new diagnostic for measurements of the fuel ion ratio—i.e. the tritium to deuterium density ratio. Measurements of the fuel ion ratio will be important for plasma control and machine protection in future experiments with burning fusion plasmas. Here we examine the theoretical basis for fuel ion ratio measurements by CTS. We show that the sensitivity to plasma composition is enhanced by the signatures of ion cyclotron motion and ion Bernstein waves which appear for scattering geometries with resolved wave vectors near perpendicular to the magnetic field. We investigate the origin and properties of these features in CTS spectra and give estimates of their relative importance for fuel ion ratio measurements.
特定散射几何条件下，集体汤姆孙散射（CTS）测量对磁约束聚变等离子体的成分敏感。因此，CTS有望成为一种测量燃料离子比（即氘氚密度比）的新诊断手段。燃料离子比的测量对于未来燃烧等离子体实验中的等离子体控制和机器保护至关重要。本文研究了利用CTS测量燃料离子比的理论基础。我们证明，当散射几何满足波矢近垂直于磁场方向时，离子回旋运动与离子伯恩斯坦波的特征会增强CTS信号对等离子体成分的敏感性。我们分析了这些特征在CTS谱中的起源与性质，并评估了它们对燃料离子比测量的相对重要性。