Development of COCHISE UV Absorption System.
Abstract
Under this program PSI developed a resonance lamp to be used to measure number densities of N(2D) and N(2P) in the COCHISE facility using the technique of vacuum ultraviolet resonance absorption. The lamps consist of sapphire tubes through which argon containing a trace of molecular nitrogen flows. A low power microwave discharge through the gas excites the VUV resonance lines which are diagnostic of the atomic nitrogen metastables (149.3 nm for N(2D) and 174.3 nm N(2P). An interference filter is used to isolate the appropriate resonance multiplet, and the radiation, after traversing the COCHISE reaction zone twice, is detected with a solar-blind photomultiplier. The major lamp-design criterion is dictated by the important excitation mechanisms in the lamp. VUV resonance-line excitation mechanisms are discussed in detail, and experimental methods for elucidating these mechanisms are presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1981
- Accession Number
- ADA111828
Entities
People
- H. C. Murphy
- L. G. Piper
- W. T. Rawlins
Organizations
- Physical Sciences (United States)