Head-on collision of two ion-acoustic solitons in pair-ion plasmas with nonthermal electrons featuring Tsallis distribution

Abstract

Abstract The head-on collision between two ion-acoustic solitons (IASs) is studied in pair ions plasmas with hybrid Cairns–Tsallis-distributed electrons. The chosen model is inspired from the experimental studies of Ichiki et al. [Phys. Plasmas 8, 4275 (2001)]. The extended Poincaré–Lighthill–Kuo (PLK) method is employed to obtain the phase shift due to the IASs collision. Both analytical and numerical results reveal that the magnitude of the phase shift is significantly affected by the nonthermal and nonextensive parameters (α and q), the number density ratios (μ and υ) as well as the mass ratio σ. For a given mass ratio σ ≃ 0.27 $\sigma \simeq 0.27$ (Ar+, SF 6 − ${\text{SF}}_{6}^{-}$ ), the magnitude of the phase shift Δ Q ( 0 ) ${\Delta}{Q}^{\left(0\right)}$ decreases slightly (increases) with the increase of q (α). The effect of α on Δ Q ( 0 ) ${\Delta}{Q}^{\left(0\right)}$ is more noticeable in the superextensive distribution case (q < 1). As σ increases [ σ ≃ 0.89 $\sigma \simeq 0.89$ (Xe+, SF 6 − ${\text{SF}}_{6}^{-}$ )], the phase shift becomes wider. In other terms, the phase shift was found to be larger under the effect of higher densities of the negative ions. Our findings should be useful for understanding the dynamics of IA solitons’ head-on collision in space environments [namely, D-regions ( H + ${\text{H}}^{+}$ , O 2 − ${\text{O}}_{2}^{-}$ ) and F-regions (H+, H−) of the Earth’s ionosphere] and in laboratory double pair plasmas [namely, fullerene (C+, C−) and laboratory experiment (Ar+, F−)].