RADIATION MEASUREMENTS FROM A PULSED HIGH-PRESSURE NITROGEN ARC.
Abstract
The program was an experimental and theoretical determination of the ultraviolet and vacuum ultraviolet emission from pulsed high pressure nitrogen arcs at pressures up to 1000 atm. For this purpose, a pressure vessel was designed and constructed for the containment of gas pressures up to 1000 atm. In addition, an ignition mechanism, which allowed breaking down of 1000 atm nitrogen arc gaps of 1/4 inch and a pulse forming network, which discharged rectangular current pulses of 2 - 10 kiloamperes magnitude and 650 microseconds duration through the 1000 atm nitrogen was designed and constructed. The breakdown apparatus utilized an ignition wire across the gap. High speed pictures of the discharge showed that a luminous plume, with 'hot spots', and not a cylindrical discharge, resulted from the discharge. Photographic spectra showed the 1000 atm nitrogen arc emission was primarily a continuum in the spectral region 1950 - 3000 A; no line emission was observed in the spectral region 1450 - 3000 A. Although local thermodynamic equilibrium was expected, the radiation pulse shapes at several wavelengths in the region 1600 - 4000 A showed erratic behavior and a quasi-stationary state was obtained at all studied wavelengths, only near the end of the rectangular discharge (500 - 700 microseconds after ignition). Quantitative measurements of the spectral radiance of a 1000 atm nitrogen arc with 4 kiloamperes current in the region 1700 - 4000 A at this quasi-stationary state, showed that the emission was a continuum, peaking at 2500 - 3000 A, and becoming extremely weak at wavelengths smaller than 1900 A. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1968
- Accession Number
- AD0680467
Entities
People
- F. N. Mastrup
- R. Goldstein