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Voltage - Current ( V— i) characteristics in low pressures electrical discharges in neon have been studied as part of an investigation of the excitation processes in the positive column of glow discharges.
Measurements have been carried out over pressure range of 0. 1 - 15 m. bar, and currents up to 30 mA, and tubes with bores 3 - 20 mm. Various cathode systems ( plane, hollow and heated coated) have been used, the advantages and drawbacks of different cathode systems will be discussed.
Voltage - current relationships for various discharge conditions (pressure, current cathode system, tube’s diameter and length) have been investigated and the electric fileld also has been measured in each case.
Similar experiments have been carried out using argon and argon - neon mixtures.