Laser-Induced Flourescences due to the Stark-Forbidden and the Electric Quadrupole Transitions in a Discharge Plasma

放电等离子体中斯塔克禁止和电四极跃迁引起的激光诱导荧光

基本信息

批准号：
05680395
负责人：
ODA Toshiatsu
金额：
$ 1.41万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

The purpose of this research is to observe in detail the laser-induced fluorescence associated with the Stark-forbidden and the electric quatrupole transitions in a hollow cathode discharge and to develop new diagnostics for electric field distribution in the sheath with applications of the laser-induced fluorescence observation. Our main results are as follows :1.Polarization of the fluorescences associated with the resonance, the Stark-forbidden and the electric quadrupole transitions from the Hel 2^1S state were observed in a plane parallel hollow cathode discharge by using laser-induced fluorescence method.A collisional-radiative model was developed to investigate effect of the collisional processes in the plasma on the fluorescences.2.The electric field distribution in the cathode dark space was determined more accurately than in our previous experiments from measured intensity ratio of the fluorescence due to the Stark forbidden to that due to the quadrupole transitions.3.Another new method was also developed to determine the electric field distribution in plasmas from measurement of only the polarization of the fluorescence which is due to both the Stark-forbidden and the quadrupole trnasitions in the dark space. The lower limit of the measurementfor the present plasma was estimated to be about 10 V/cm.4.As a future plan, a procedure will be developed to correct the effect of the charged-particle-produced microfield in rather dense plasmas, and also investigation using the triplet level system will be performed to extend this measurement.

本研究的目的是详细观察与空心阴极放电中的斯塔克禁阻和电四极跃迁相关的激光诱导荧光，并通过应用激光诱导荧光来开发鞘内电场分布的新诊断方法。荧光观察。主要研究结果如下：1.利用激光诱导荧光方法，在平面平行空心阴极放电中观察到了与共振、Stark禁阻和Hel 2^1S态电四极跃迁相关的荧光偏振。 .建立了碰撞-辐射模型来研究等离子体中的碰撞过程对荧光的影响。2.由于测量的荧光强度比，可以比我们之前的实验更准确地确定阴极暗空间中的电场分布。 3.还开发了另一种新方法，通过仅测量由斯塔克禁止和四极跃迁引起的荧光偏振来确定等离子体中的电场分布黑暗的空间中。目前等离子体的测量下限估计约为 10 V/cm。4。作为未来的计划，将开发一种程序来校正相当密集的等离子体中带电粒子产生的微场的影响，并且还将使用三重态能级系统进行调查以扩展该测量。