微波等离子体炬光源基本特性的研究

用计算机化断层扫描成象技术研究了微波等离子体炬(MPT)放电的发射轮廓,证明该光源具有良好的对称性,并有一个有利于样品引入的中央通道,最佳分析区在炬管上方5～10 mm,用激光Thomson散射和Rayleigh散射技术测定了ArMPT和HeMPT放电的电子温度、电子密度和气体温度,证明MPT放电的电子温度很高而气体温度较低,是一种非热光源。其中的高能电子处于过布居状态,具有很高的激发能力。

A Study on Fundamental Properties of Microwave Plasma Torch Source

The emission profile of microwave plasma torch (MPT) discharge was studied with computed tomography. It was shown that the source was in good symmetry and there was a central channel which is beneficial to the introduction of samples. The optimum analytical zone is in the region from 5 to 10 mm above the top of the torch. The laser Thomson scattering and Rayleigh scattering were used to study the electron temperatures, electron number densities and gas temperatures of ArMPT and HeMPT discharges. The electron temperature of the MPT was shown to be very high and the gas temperature was relative low and, therefore , it was a non-thermal emission source. There existed an over-population of high-energy electrons and the excitation power of the source was very high.