HL-2A装置中利用可见光谱段轫致辐射测量有效离子电荷数

Measurement of effective ion charge using visible bremsstrahlung on HL-2A tokamak

通过测量可见光谱段的轫致辐射(λ=535.1nm)强度,结合等离子体电子密度和电子温度,HL-2A装置上的多道轫致辐射测量系统实现了平均有效离子电荷数以及有效离子电荷数径向分布的测量。实验结果显示,当等离子体电子密度从1×1019m-3升高到4×1019m-3,有效离子电荷数从5下降到2附近。对于电子密度高于3×1019m-3时的放电,多道轫致辐射测量系统在整个等离子体区域都能采集到足够强的信号,可以测量有效电荷数的径向分布。

The multichannel bremsstrahlung measurement system on HL-2A tokamak has been using to observe the intensity of visible （535.1nm） bremsstrahlung radiation. Combined the intensity with plasma electron density and electron temperature, the effective ion charge measurements can be obtained on HL-2A tokamak. The experimental results show that when the plasma electron density increases from 1×10^19m-3 to 4×10^19m-3, the effective ion charge number changes from 5 down to around 2. The bremsstrahlung radiation signal intensity is proportional to the quadratic plasma density. When the electron density is higher than 3×10^19m-3, the multichannel bremsstrahlung measurement system can collect sufficient signal through the plasma, which enables the measurement of effective ion charge radial profile.