Localized Dust Acoustic Solitons in Electron-Depleted Dusty Plasmas With κ-Gurevich Distributed Ions

Abstract

A first theoretical attempt is made to investigate the adiabatically trapped suprathermal ions effect on dust acoustic (DA) solitons in electron-depleted dusty plasmas. Our investigation is motivated by space and laboratory plasma observations of plasmas containing suprathermal particles, resulting from long-tailed distributions, combined with trapped particles in a finite region of phase space. For this goal, the 1-D <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\kappa $ </tex-math></inline-formula> -Gurevich distribution, which describes the adiabatic trapping of suprathermal ions, is constructed, and the associated density expression is derived. The reductive perturbation method (RPM) has been adopted to establish a modified Kortweg-de-Vries (mK-dV)-like equation, and analyze its comportment. The numerical investigation revealed that the main properties (phase velocity, amplitude, and width) of small DA solitons are significantly affected by adiabatically trapped suprathermal ions. In particular, we have found that as the suprathermality of the ions increases, the DA soliton amplitude decreases while its width increases. The significant changes induced by the presence of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\kappa $ </tex-math></inline-formula> -Gurevich distributed ions on the transported energy and electrical field of DA solitons are also analyzed. We have shown that when the ions evolve far from their Maxwellian trapping (i.e., as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\kappa $ </tex-math></inline-formula> decreases), the DA soliton energy quantity (bipolar electric field) associated with electronically depleted dusty plasma becomes smaller (stronger). The results of the present study provide new insight into established findings on this issue.