Effect of Nonthermal Charge Gradient Force on Arbitrary Amplitude Dust-Acoustic Solitons in Nonuniform Charge-Varying Dusty Plasma

Abstract

This study examines the influence of the nonthermal charge gradient and polarization forces on large-amplitude dust-acoustic (DA) waves in nonuniform, charge-varying dusty plasmas. A new expression for the nonthermal charge gradient is derived, the magnitude of which depends on the proportion of nonthermal ions. Using the pseudo-potential approach, the impact of this force on nonlinear DA waves in polarized dusty plasmas composed of inertial negative dust grains, Maxwellian electrons, and nonthermal ions is explored. The results reveal that the nonthermal charge gradient force enhances the amplitude of DA solitons, affects the dust grain charge and density profiles, and leads to increased electron depletion. This analysis highlights the crucial role of the nonthermal charge gradient force in shaping DA wave behavior in both experimental and astrophysical dusty plasmas.