Linear and nonlinear analysis of Ion-Temperature-Gradient (ITG) Driven mode in the asymmetric Pair-Ion Magnetoplasma

TL;DR

This paper investigates the linear and nonlinear behavior of ion-temperature-gradient driven modes in pair-ion plasmas, revealing how instability growth rates and solitary wave amplitudes depend on plasma parameters and electron distributions.

Contribution

It presents new analytical and numerical analysis of ITG modes in asymmetric pair-ion plasmas, including the existence of soliton structures and their dependence on plasma conditions.

Findings

Growth rate of instability increases with eta.

Amplitude of solitary waves increases with ion to electron density ratio.

Solitary structures are sensitive to non-thermal electron distributions.

Abstract

We have investigated linear and nonlinear dynamics of ion-temperature-gradient driven drift mode for Maxwellian and non Maxwellian pair-ion plasma embedded in an inhomogeneous magnetic field having gradients in ion's temperature and number density. Linear dispersion relations are derived and analyzed analytically as well as numerically for different cases. It has been found that growth rate of instability increases with increasing eta. By using the transport equations of Braginskii, model, a set of nonlinear equations are derived. In the nonlinear regime, soliton structures are found to exist. Our numerical analysis shows that amplitude of solitary waves increases by increasing ion to electron number density ratio. These solitary structures are also found to be sensitive to non thermal kappa and Cairns distributed electrons. Our present work may contribute a good illustration of the observation of nonlinear solitary waves driven by the ITG mode in magnetically confined pair-ion plasmas and space pair-ion plasmas as the formation of localized structures along drift modes is one of the striking reasons for L-H transition in the region of improved confinements in magnetically confined devices like tokamaks.