Obliquely nonlinear solitary waves in magnetized electron–positron–ion plasma

Abstract

This study focused on nonlinear ion-acoustic solitary structures (IASS) in a magnetized plasma system that is kappa distributed comprising electrons, positrons, and ions (e–p–i) using a fluid theory approach. A novel nonlinear inverse dispersion relation peculiar to this complex plasma environment was derived. The dispersive properties of ion-acoustic waves in magnetized e–p–i plasma environment were investigated considering the influence of various superthermal of electrons and positrons \((\kappa _{e}~\textrm{and} ~\kappa _{p})\), unperturbed positron to ion density ratio, p, electron to ion density ratio, \((\delta )\), ion to electron temperature ratio, \((\sigma )\). By numerically analyzing the impact of plasma properties, particularly the nonlinear dispersion characteristics in a magnetized e–p–i plasma. The influence of the external magnetic field (obliqueness) angle, \(\theta\), which alters the frequency value of \((\omega ^{2})\). It was found that the values of \(\delta\), the frequency \(\omega ^{2}\) of IASS waves decreases with increasing \(\delta\). This result has significant implications for understanding the dynamics of various astrophysical settings, such as the solar wind. However, when \(\delta > 0\), the curves become more nonlinear, indicating the waves become more dispersive. Further, it is discovered that as the value of \(\theta\) for \(+~\omega ^{2}\) solution increases, the shape of the dispersion curve does not significantly change. In contrast, it is observed from the \(-~\omega ^{2}\) solution that for all values of angle \(\theta\), frequency decreases with increasing angle \(\theta\). This is because the ion-acoustic mode is strong at the propagation angle at \(\theta = 0^{\circ }\) and weakens as the propagation angle increases, eventually disappearing at \(\theta = 90^{\circ }\). Thus, these findings provide an appreciable understanding of the dispersion characteristics of obliquely propagating IASS modes in a magnetized e–p–i plasma. In conclusion, our results provide important and new information on the interaction of plasma parameters in complex astronomical (natural) and laboratory (artificial) settings.