Interaction of ion-acoustic solitons with electron beam in warm plasmas with superthermal electrons

TL;DR

This paper investigates how ion-acoustic solitary waves interact with an electron beam in warm plasmas with superthermal electrons, analyzing their propagation, characteristics, and coexistence of different polarity solitons.

Contribution

It introduces a comprehensive nonlinear analysis of IASWs in superthermal electron plasmas with an electron beam, including effects of various physical parameters and polarity coexistence.

Findings

Both negative and positive polarity solitons can coexist.

Superthermality affects amplitude and width of solitons.

Electron beam influences soliton properties and interactions.

Abstract

Propagation of ion-acoustic solitary waves (IASWs) is studied using the hydrodynamic equations coupled with the Poisson equation in a warm plasma consisting of adiabatic ions and superthermal (Kappa distributed) electrons in presence of an electron-beam component. In the linear limit, the dispersion relation for ion-acoustic (IA) waves is obtained by linearizing of basic equations. On the other hand, in the nonlinear analysis, an energy-balance like equation involving Sagdeev's pseudo-potential is derived in order to investigate arbitrary amplitude IA solitons. The Mach number range is determined in which, propagation and characteristics of IA solitons are analyzed both parametrically and numerically. The variation of amplitude and width of electrostatic (ES) excitations as a result of superthermality (via) and also the physical parameters (ion temperature, soliton speed, electron-beam density and electron-beam velocity) are examined. A typical interaction between IASWs and the electron-beam in plasma is confirmed. It is also found that ES solitons with both negative polarity (rarefactive solitons) and positive polarity (compressive solitons) can coexist in plasma. Furthermore, the small but finite amplitude limit of IASWs is investigated and it is showed that this limit is restricted to negative potential pulses.