Nonlinear dynamics of the dissipative ion-acoustic solitary waves in anisotropic rotating magnetoplasmas

This study explores the nonlinear dynamics of ion-acoustic waves (IAWs) in a magnetized, collisional, anisotropic rotating plasma that includes hot ions, superthermal electrons, and positrons. Anisotropic ion pressure is defined using the Chew–Goldberger–Low theory. Our linear analysis shows that pressure anisotropy notably impacts wave frequency, particularly for shorter wavelengths, and identifies a threshold wavenumber beyond which wave propagation is impossible. We derive a nonlinear damped Zakharov–Kuznetsov equation by applying the reductive perturbation technique. This equation describes the phase velocity and profile of ion-acoustic solitary waves, which are significantly influenced by superthermal, electron–positron temperature ratio, pressure anisotropy, the Coriolis force, and ion collisions. Our numerical analysis reveals that IAWs propagate in the plasma in a direction parallel to the magnetic field with a phase velocity that is unaffected by the plasma rotation frequency <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:msub> <m:mrow> <m:mi mathvariant="normal">Ω</m:mi> </m:mrow> <m:mrow> <m:mn>0</m:mn> </m:mrow> </m:msub> </m:math> {Ω }₀ , the magnetic field through <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:msub> <m:mrow> <m:mi>ω</m:mi> </m:mrow> <m:mrow> <m:mi>c</m:mi> <m:mi>i</m:mi> </m:mrow> </m:msub> </m:math> {ω }ci , or the perpendicular pressure component <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:msub> <m:mrow> <m:mi>P</m:mi> </m:mrow> <m:mrow> <m:mo>⊥</m:mo> </m:mrow> </m:msub> </m:math> {P}⊥ . The phase velocity increases with the <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mi>κ</m:mi> </m:math> κ index and parallel pressure <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:msub> <m:mrow> <m:mi>P</m:mi> </m:mrow> <m:mrow> <m:mo>‖</m:mo> </m:mrow> </m:msub> </m:math> {P} and decreases with the positron temperature ratio <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mi>σ</m:mi> </m:math> σ . Moreover, it is found that the wave amplitude decreases with increasing ion pressure <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:mo stretchy="false">(</m:mo> <m:mrow> <m:msub> <m:mrow> <m:mi>P</m:mi> </m:mrow> <m:mrow> <m:mo>‖</m:mo> </m:mrow> </m:msub> </m:mrow> <m:mo stretchy="false">)</m:mo> </m:mrow> </m:math> ({P}) and the electron–positron temperature ratio <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:mo stretchy="false">(</m:mo> <m:mrow> <m:mi>σ</m:mi> </m:mrow> <m:mo stretchy="false">)</m:mo> </m:mrow> </m:math> (σ ) . On the contrary, the amplitude increases with rising superthermality <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mi>κ</m:mi> </m:math> κ , while collisions cause the wave amplitude to spread. The Coriolis force exclusively affects the width of electrostatic waves. The results of this study are particularly relevant for understanding wave behavior in astrophysical and space environments, especially within Earth’s magnetosphere, where nonthermal electrons and positrons coexist with anisotropic pressure ions.