Dusty plasma has been studied in dc glow discharge with standing striation formed in neon. The theoretical method of dust particle charge determination is proposed. This method is based on the calculation of the ion and electron fluxes on the dust particle surface in a spatially periodic field of striation. The electron flux is calculated through the use of non-local electron energy distribution function (EEDF), which is formed by inhomogeneous strata potential. The calculation of dust particle charge using proposed theoretical method are compared with those in which the used EEDF was assumed to be Maxwell EEDF. Under the conditions of standing P-striations at low pressures of neon the numerical calculations and the measurements are performed. An experimental method of dust particle charge determination is applied in the dc discharge condition. Discharge current is modulated at low-frequency in order to determine the dust charge through the relaxation oscillation of a single dust particle. The calculation of the dust particle charge with the help of measured frequency and damping coefficient of the oscillations is made. The dust particle charges obtained by using two independent methods are in good agreement.

The forced vertical oscillations of a single dust particle trapped in a standing striation are investigated. The particle oscillations associated with the displacement of the striation are induced by square wave modulation of the discharge current. Amplitude−frequency characteristics with respect to pressure are measured. The resonance frequency, the logarithmic decrement and the amplitude of resonance peak are determined. In order to obtain the eigenfrequency value, the phase shift of the forced dust particle oscillations is measured and the velocity resonance investigated. The calculation of the dust particle charge is made with the help of the eigenfrequency. A quantitative description of the resonance behaviour of the dust particle based on the theory of the forced harmonic oscillator is made. The Q-factor of a dusty plasma system is measured for the first time, and the obtained value compared with Q-factors of dusty plasma oscillatory systems previously investigated in rf plasma.

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