Dust-acoustic solitary waves in a magnetized dusty plasma with nonthermal electrons and trapped ions

Abstract

The nonlinear propagation of electrostatic dust-acoustic (DA) waves in a magnetized dusty plasma consisting of negatively charged mobile dusts, nonthermal fast electrons and trapped ions with vortex-like distribution is studied. Using the reductive perturbation technique, a Korteweg-de Vries (KdV)-like equation is derived which governs the dynamics of the small-amplitude solitary waves in a magnetized dusty nonthermal plasma. It is found that due to the dust thermal pressure, there exists a critical value (β c ) of the nothermal parameter β (> 1), denoting the percentage of energetic electrons, below which the DA solitary waves cease to propagate. The soliton solution (travelling wave) of the KdV-like equation is obtained, and is shown to be only of the rarefactive type. The properties of the solitons are analyzed numerically with the system parameters. It is also seen that the effect of the static magnetic field (which only modifies the soliton width) becomes significant when the dust gyrofrequency is smaller than one-tenth of the dust plasma frequency. Furthermore, the amplitude of the soliton is found to increase (decrease) when the ratio of the free to trapped ion temperatures (σ) is positive (negative). The effects of the system parameters including the obliqueness of propagation (l z ) and σ on the dynamics of the DA solitons are also discussed numerically, and it is found that the soliton structures can withstand perturbations and turbulence during a considerable time. The results should be useful for understanding the nonlinear propagation of DA solitary waves in laboratory and space plasmas (e.g., Earth's magnetosphere, auroral region, heliospheric environments etc.).

Oblique Propagation of Nonlinear Solitary Waves in Magnetized Plasma with Nonextensive Electrons

“…The decrease of v 0 with γ also becomes clear from the expression (6) where  cos 0  v and becomes zero for γ = 90 0 . This decreasing trend of v 0 with γ is similar to that observed by Misra and Wang [37]. In order to investigate the electrostatic propagation, we consider small oblique angle.…”

Stability of dust-acoustic solitary waves in magnetized dusty plasmas: effect of polarization force and degenerate electron temperature

“…An ambient magnetic field is assumed to lie along z − direction, i.e., B B z 0 0 = . The dynamics of low frequency DAWs in the considered plasma medium, whose phase speed, v ph = ω/k, is far smaller than the thermal speed of trapped electrons, v te , and κ-nonthermal ions, v ti , but far larger than the dust thermal speed, v td , i.e., v td = v ph = v te , v ti [1], can be governed by the following set of three dimensional (3D) equations [29]…”

Dust-acoustic solitary and cnoidal waves in a dense magnetized dusty plasma with temperature degenerate trapped electrons and nonthermal ions

“…In this dense plasma environments, the thermal pressure of electrons is dominated by the degenerate pressure for the formation of wave, and the electron can be treated as degenerate. [51] The dynamics of dust-acoustic waves, whose phase speed, v ph (= ω/k), is much larger than the dust thermal speed, v td , but much smaller than the fermi speed of trapped electrons, v tf , and thermal speed of κ−non-thermal ions, v ti , i.e., v td = v ph = v tf , v ti , can be described by the following 3-D evolution equations [52] • ( ) ( )…”