Dynamics of the Current-Voltage Characteristic and the Potential in a Triple Plasma Machine

Abstract: A model for the static current voltage characteristic of a thin collisionless plasma inwich an electrical double layer is present is used for simulating the behaviour of anelectrical circuit in wich the plasma is a component. The numerical results thusobtained are compared to experimental results and found to be quite accurate forlow frequencies and amplitudes. The discrepancy between simulations andexperiments are found to be caused mainly by effects of hysteresis in the plasma.The hysteresis is then shown to be caused by 'slow ions'. The hysteresis is dividedinto three typical cases and a method to predict wich case to expect for a certaincombination of applied potential and frequeny is presented. The formation of thedouble layer in time and space is also studied by means of Langmuir probe measurements. Comments are also made concerning the internal plasma potential for different frequencies of the applied potential.