Mikiko Hagi

A Method of Measurement of Plasma Conductivity. I. : Theoretical Approach

It is shown that the plasma conductivity can be evaluated from the change in magnetic flux in the plasma of an applied electromagnetic field. The evaluation requires no detailed knowledge of the electron collision frequency. This method, not being based on the usual conductor approximation will prove useful if a method of determining the magnetic flux change is established successfully.

A METHOD OF MEASUREMENT OF PLASMA CONDUCTIVITY. II. EXAMPLE OF MEASUREMENT

A measurement of plasma conductivity is described, which is based on the method theoretically discussed in the previous note. The plasma tube is inserted in a single turn coil of a LC oscillator, and the shift in the resonance frequency, Δf, due to the insertion is observed. From Δf the change in the magnetic flux penetrating the coil can be evaluated, and from the latter the plasma conductivity can be determined. The results are in satisfactory agreement with the conductivity values obtained by the usual probe method.

Ion Acoustic Waves in Mercury‐Vapor Discharges

The external excitation of the ion acoustic waves is examined. The propagation and reflection of the waves and the standing waves between the probe and anode are observed.