Nonlinear ion-acoustic structures in dusty plasma with superthermal electrons and positrons

Abstract

Nonlinear ion-acoustic structures are investigated in an unmagnetized, four-component plasma consisting of warm ions, superthermal electrons and positrons, as well as stationary charged dust impurities. The basic set of fluid equations is reduced to modified Korteweg-de Vries equation. The latter admits both solitary waves and double layers solutions. Numerical calculations indicate that these nonlinear structures cannot exist for all physical parameters. Therefore, the existence regions for both solitary and double layers excitations have been defined precisely. Furthermore, the effects of temperature ratios of ions-to-electrons and electrons-to-positrons, positrons and dust concentrations, as well as superthermal parameters on the profiles of the nonlinear structures are investigated. Also, the acceleration and deceleration of plasma species have been highlight. It is emphasized that the present investigation may be helpful in better understanding of nonlinear structures which propagate in astrophysical environments, such as in interstellar medium.

Nonlinear ion-acoustic structures in a nonextensive electron–positron–ion–dust plasma: Modulational instability and rogue waves

“…In the electron-positron-ion-dust (EPID) plasmas, the charge of the dust grains can be either negative or positive when the number of positrons depositing on them is either smaller or larger than the number of electrons. Accordingly, it is interesting and important to study ion-acoustic waves (IAWs) in the EPID plasmas [12,13].…”

Dynamical behaviour of non‐linear quantum ion acoustic wave in weakly magnetized electron–positron–ion plasma

“…The presence of a positron component in conventional e-i plasma can modify the features of linear and non-linear wave structures. [22][23][24][25] Surko and Murphy [26] theoretically predicted that the annihilation of electrons and positrons is relatively unimportant over a wide range of parameters, and they also reported that, for the propagation of IAWs in e-p-i plasmas, the e-p pair annihilation can be neglected in the sense that the electron-positron lifetime is much larger than the characteristic time scale for collective oscillations. [21] The linear and non-linear propagation of IAWs in an unmagnetized e-p-i plasma have been extensively studied for the past few years.…”

Arbitrary amplitude ion-acoustic waves in a multicomponent plasma with superthermal species

“…Based on superthermal assumption, many authors have been studied the effect of superthermal particles (electrons, positrons, and ions) in different types of plasma environments. 4,8,9,[18][19][20] An electron-positron-ion (e-p-i) plasma is a fully ionized gas consisting of electrons and positrons having equal masses and charges with opposite polarity. The e-p-i plasmas are found not only in early universe 21 but also in astrophysical environments such as in magnetosphere of pulsars, 22 active galactic nuclei, 23 interstellar medium.…”