Book Description
Experimental data resulting from an investigation of the electroacoustic probe in an argon afterglow plasma for a planar geometry indicates the value of the probe as a diagnostic tool. It is suited to airborne payloads because of its small size and rugged construction. In carrying out the study, some of the parameters that were varied were the pressure (range = 100 to 1000 micro m), input power to the probe (range = 40 dB), and frequency of input signal (350 to 600 MHz). The effect of changing physical dimensions of the probe was also considered. Electroacoustic probe predictions of the electron density gradients close to a surface were found to compare closely with the electron density gradients obtained with a floating double Langmuir probe. Treating the electroacoustic probe as similar to a resonant circuit produced some preliminary results that show up as familiar Q values. Both linear and nonlinear responses of the electroacoustic probe are illustrated. One nonlinear phenomenon--induced oscillations in sections of the resonance curve--is discussed in detail. (Author).