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The dust–ion–acoustic (DIA) solitary wave (SW) propagation in a magnetized dusty plasma consisting of mobile positive and heavy negative ions, nonthermal electrons and positrons is presented. By using reductive perturbation technique, three dimensional Zakharov–Kuznetsov (Z–K) equation is derived and the solution is obtained by using the tan-hyperbolic method. Here, the dust grain charging process by plasma constituents is represented by the equation following orbital motion limited (OML) theory. The characteristics features of solitary wave amplitudes arising due to different plasma parameters such as ions mass ratio, nonthermal parameters of electrons and positrons, temperature ratio of electrons and positrons, ions density ratio, and dust density ratio are analyzed. In this analysis, the influence of nonthermal electrons on solitary wave amplitude variation is observed as more significant than that of nonthermal positrons. The findings of this work can be helpful in understanding D, E, and F regions of the Earth's ionosphere, its mesosphere region, solar photosphere, and Titan's ionosphere. [ABSTRACT FROM AUTHOR]

The effect of energetic electrons on dust charging for different types of dust is studied in hydrogen plasma. The hydrogen plasma is produced by hot cathode filament discharge method in a dusty plasma device. A full line cusped magnetic field cage is used to confine the plasma elements. To study the plasma parameters for various discharge conditions, a cylindrical Langmuir probe having 0.15 mm diameter and 10.0 mm length is used. An electronically controlled dust dropper is used to drop the dust particles into the plasma. For different discharge conditions, the dust current is measured using a Faraday cup connected to an electrometer. The effect of secondary emission as well as discharge voltage on charging of dust grains in hydrogen plasma is studied with different dust. [ABSTRACT FROM AUTHOR]

An experimental study has been performed into the variation of charge on dust grains with change in the ambient plasma conditions. A dust beam containing submicron sized silver grains was passed through plasma. The dust grains were charged by the plasma particles as well as by primary electrons from the filament. An increase in the filament current increased both the plasma density and the number density of the primary electrons. The grain charge was found out both from the deflection of the dust grains and also from the floating potential. The experimental observations shows that the secondary emission caused by the primary electrons significantly influenced and played a prominent role in the establishment of charge on the grains. [ABSTRACT FROM AUTHOR]