Head-on-collision of modulated dust acoustic waves in strongly coupled dusty plasma

Abstract

The derivative expansion perturbation method is applied to a strongly coupled dusty plasma system consisting of negatively charged dust grains, electrons, and ions. The basic equations are reduced to a nonlinear Schrödinger type equation appropriate for describing the modulated dust acoustic (DA) waves. We have examined the modulation (in) stability and the dependence of the system physical parameters (angular frequency and group velocity) on the polarization force variation. Finally, the extended Poincaré-Lighthill-Kuo technique is employed to investigate the head-on collision (HoC) between two DA dark solitons. The analytical phase shifts and the trajectories of these dark solitons after the collision are derived. The numerical illustrations show that the polarization effect has strong influence on the nature of the phase shifts and the trajectories of the two DA dark solitons after collision.

Instability of nonplanar modulated dust acoustic wave packets in a strongly coupled nonthermal dusty plasma

“…This suggests that the spherical waves are more structurally stable to perturbations than the cylindrical waves. As the used numerical physical parameter values are inspired from recent experimental data, 23,24,26,49 we believe that the present results are helpful to existing and forthcoming experimental and space observations, where nonthermal SCDP is present. 48 APPENDIX: THE EXPLICIT EXPRESSIONS OF THE COEFFICIENTS MENTIONED IN EQS.…”

“…Moreover, we consider the viscosity contribution [g(f) is the bulk (shear) viscosity coefficient, and g L ¼ f þ ðg=3Þ is the longitudinal viscosity coefficient] is small compared to the compressibility contribution. 24 As discussed in Refs. 21 and 24, simulation and model calculations typically show that g L $ 0:08 for C s $ 10, whereas l d $ 1 in that region.…”

“…On the other side, the nonlinear analyses produce new salient features for the DA solitary waves. [22][23][24][25][26] For example, the DA solitary and shock waves are found to exist with negative potential only in a SCDP including nonthermal ions and Boltzmann distributed electrons. 22 The effect of the polarization force on the propagation of linear and nonlinear DA waves has been considered by Mamun and his coworkers 23 in different SCDP models.…”

“…20 The coupling between particles can be depicted from the screened Coulomb coupling parameter: (SCDP) both theoretically and experimentally. [21][22][23][24][25][26] The linear analyses 21 have revealed that strong correlations introduce modifications to the DA wave modes such as new dispersion corrections and additional damping effects. On the other side, the nonlinear analyses produce new salient features for the DA solitary waves.…”

“…These studies reveal that the phase speed of the DA waves, as well as the dust density perturbation, increase (decrease) with the increase of nonthermal ions (polarization force), and that the potential associated with the DA waves decreases with the increase of the equilibrium dust number density. El-Labany et al 24 introduced the first study of head-on-collision of two modulated DA wave envelope solitons in SCDP within the NLSE framework in both of hydrodynamic and kinetic regimes. Since the polarization effects are included in their models, they considered only Maxwellian distributed species and planar geometry.…”