Expanding argon plasma interacting with lithium surface

In this thesis, the interaction between Ar Plasma and lithium is studied by Langmuir probe and Spectrometer. We have studied the effects of the applied discharge current, the gas flow rate, the magnetic field on emission spectrum, electron temperature and electron density. The experimental results show that spectrum intensity, electron temperature and electron density all increase with the increasing discharge current, gas flow rate or magnetic field when the other experimental conditions were fixed, and it is also found that the intensity of Li-670.78 nm increases slowly at first and then increases rapidly, at last, it tends to be stable figure at the beginning of experiment. What is more, spectrum of lithium (670.78 nm) is also detected at the first diagnostic window (viewing window).