Elementary processes of atmospheric-pressure molecular gas discharge plasmas in non-equilibrium state and their diagnostics with OES

我们回顾了大气压等离子体的光学发射光谱(OES)的基本原理，特别是它在处理等离子体方面的应用。描述了碰撞辐射模型以了解激发态的激发动力学和布居分布，以考察电子的温度和密度。结果表明，对于一般过程等离子体，通常采用电晕平衡作为激发动力学的合理假设。研究了大气压Ar等离子体和低压氮气等离子体的谱线强度测量方法。从基本过程和碰撞辐射模型出发，从理论上研究了大气压下非平衡态电离Ar等离子体中Ar原子激发态的布居密度。讨论了激发态布居数与电子温度和气体温度的关系。

We review fundamentals of optical emission spectroscopy (OES) of plasmas of atmospheric pressure and, in particular, its applications to processing plasmas. Collisional radiative model is described to understand the excitation kinetics and population distributions of excited states in order to examine the electron temperature and density. It is shown that corona equilibrium is often adopted as justifiable assumption of excitation kinetics for general processing plasmas. Line intensity measurement methods are studied for atmospheric-pressure Ar plasma and low-pressure N2 plasma. Population densities of excited states of argon atoms are theoretically examined for ionizing argon plasma in a state of non-equilibrium under atmospheric pressure from the viewpoint of elementary processes with collisional radiative model. The dependence of excited state populations on the electron and gas temperatures is discussed.