Penning ionization ternary gas mixtures for diffuse discharge switching applications
The increase in the total ionization produced by high-energy ..cap alpha.. particles in Ar/C/sub 2/F/sub 6/ mixtures, which have conduction and insulation properties appropriate for use in diffuse discharge switching applications by addition of low ionization energy additives has been quantitatively studied. The energy to produce an electron-positive ion pair (ip) W in C/sub 2/F/sub 6/ was found to be 34.7 eV/ip; this rather high value is attributed to the large cross section for electron impact-induced dissociation of C/sub 2/F/sub 6/. The W values of Ar/C/sub 2/F/sub 6/ mixtures have also been measured and are reported; they increase with increasing C/sub 2/F/sub 6/ content. The W values of Ar/C/sub 2/F/sub 6/ binary gas mixtures have been found to decrease by addition of C/sub 2/H/sub 2/ or 2-C/sub 4/H/sub 8/. Quantitative measurements of the W values of the ternary gas mixtures are reported. The amounts of C/sub 2/H/sub 2/ or 2-C/sub 4/H/sub 8/ in Ar/C/sub 2/F/sub 6/, which maximize the increase in total ionization have been estimated; some of these ternary gas mixtures may be useful for diffuse discharge switches sustained by external electron beams. The experimental results on the W values for the binary and ternary gas mixtures studied have been modeled and good agreement has been found between the experimental and the calculated results. From an analysis of the data it has been found that the ..cap alpha..-particle energy is partitioned between C/sub 2/F/sub 6/ and Ar approximately in the ratio 4.2:1. It has also been found that at the argon pressures employed, the probability of deexcitation of excited argon atoms by C/sub 2/F/sub 6/ (or C/sub 2/H/sub 2/ or 2-C/sub 4/H/sub 8/) molecules is more than three orders of magnitude larger than the probability of radiative deexcitation of the excited argon atoms.
- Research Organization:
- Atomic, Molecular, and High Voltage Physics Group, Health and Safety Research Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
- OSTI ID:
- 5545377
- Journal Information:
- J. Appl. Phys.; (United States), Vol. 58:2
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ARGON
ION-ATOM COLLISIONS
IONIZATION
PENNING EFFECT
CARBON FLUORIDES
ION-MOLECULE COLLISIONS
HELIUM IONS
PLASMA SWITCHES
PENNING DISCHARGES
CROSS SECTIONS
DISSOCIATION
ELECTRIC DISCHARGES
EXPERIMENTAL DATA
IONIZATION POTENTIAL
MOLECULAR IONS
ATOM COLLISIONS
CARBON COMPOUNDS
CHARGED PARTICLES
COLLISIONS
DATA
ELECTRICAL EQUIPMENT
ELEMENTS
EQUIPMENT
FLUIDS
FLUORIDES
FLUORINE COMPOUNDS
GASES
HALIDES
HALOGEN COMPOUNDS
INFORMATION
ION COLLISIONS
IONS
MOLECULE COLLISIONS
NONMETALS
NUMERICAL DATA
RARE GASES
SWITCHES
640302* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Properties & Theory