Optically Controlled Attachment Studies for Diffuse Discharge Switch Applications
Abstract
The generic properties required of the gas medium of a diffuse discharge switch are reviewed, and applied to the selection of a suitable main gas, CH4, and a number of candidate attaching gas additives for increasing the rate of recovery of the switch. The constraints placed on the latter choice include the possibility that the attachment cross section be susceptible to optical enhancement by IR irradiation using a CO2 laser. Based on a literature survey of available gases whose infrared absorption spectra overlap the output spectrum of efficient CO2 lasers, we selected four gases for further experimental study. Two of the gases chosen, perfluoropropane (C3F8), and vinyl chloride (C2H3C1), were known to have desirable attachment cross section shapes, but their cross section magnitudes were uncertain, and their temperature sensitivity unknown. In the present work we have determined that the room temperature total attachment cross section of C3F8 peaks at 2.8 eV with a value of 1.75 x 10 to the minus 17th power per sqr. cm. This 14 times smaller than the only other measurement of this type we are aware of (Kurepa, 1965). There is much better agreement with two more recently reported values unfolded from swarm experiments (Hunter and Christophorou, 1984; Spyrou and Christophorou, 1985).
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 05, 1988
- Accession Number
- ADA201269
Entities
People
- C. B. Freidhoff
- C. L. Chen
- D. K. Davies
- L. E. Kline
- P. J. Chantry