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Publication Citation: Kinetic-energy Distributions of Positive and Negative Ions in Townsend Discharges in Oxygen

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Author(s): MVVS. Rao; Richard J. Van Brunt; James K. Olthoff;
Title: Kinetic-energy Distributions of Positive and Negative Ions in Townsend Discharges in Oxygen
Published: April 01, 1999
Abstract: Translational flux-energy distributions of positive and negative ions have been measured at high electric field-to-gas density ratios (E/N) up to 40 x 10-18 V m2 (40 kTd) in diffuse, parallel-plate Townsend discharges in oxygen using an ion energy analyzer-mass spectrometer. The O2+ ion is the most abundant ion detected in the discharge, and exhibits Maxwellian energy distributions for E/N < 20 x 10 -18 V m2, which is consistent with predictions based upon the assumption that resonant symmetric charge exchange is the dominant ion-molecule collision process. The less abundant ions, O+, O2-, and O-, exhibit non-Mawellian ion kinetic energy distributions at nearly all E/N, indicative of multiple ion-molecule reactions affecting the ion transport. Mean energies are obtained for each ion as a function of E/N from analysis of the energy distributions, and symmetric charge-exchange cross sections are calculated from the data where appropriate.
Citation: Physical Review E (Statistical, Nonlinear, and Soft Matter Physics)
Volume: 59
Issue: 4
Pages: pp. 4565 - 4572
Keywords: ;cross-sections;ion-molecule reactions;kinetic-energy distributions;O2;oxygen;Townsend discharge;
Research Areas: Electronics & Telecommunications
PDF version: PDF Document Click here to retrieve PDF version of paper (7MB)