Face-to-face collisional effects of ion acoustic waves (IAWs) in multi-component unmagnetized plasma containing pair-ions, nonthermal electrons and isothermal positrons are investigated theoretically. The nonlinear Korteweg–de Vries (KdV) equations are derived employing the extended Poincaré–Lighthill–Kuo (ePLK) method to perceive the consequences of collisions of IAWs on amplitude, width and phase shift taking into account the concerned plasma parameters. This study reveals that the compressive (hump shape) and rarefactive (dip shape) solitons as well as the negative phase shifts are produced depending on plasma species densities, temperatures and collisions. The nonlinear coefficient of IAWs is increasing due to the changes in the mass ratio of positive to negative ions, density ratio of electron to positive ion and temperature ratio of electron to positron. The results of this study can be useful understanding in different regions of space (viz., upper region of Titan’s atmosphere, cometary comae and Earth’s ionosphere, etc.) and laboratory (viz., plasma processing reactor and neutral beam sources, etc.) plasmas.

从理论上研究了离子声波（IAW）在包含成对离子，非热电子和等温正电子的多组分未磁化等离子体中的面对面碰撞效应。非线性的Korteweg-de Vries（KdV）方程是使用扩展的Poincaré-Lighthill-Kuo（ePLK）方法导出的，以便考虑到相关的等离子体参数，以了解IAW的碰撞对振幅，宽度和相移的影响。这项研究表明，取决于等离子体物质的密度，温度和碰撞，会产生压缩（驼峰形状）和稀有（浸没形状）孤子以及负相移。IAW的非线性系数由于正负离子质量比的变化而增加，电子与正离子的密度比和电子与正电子的温度比。这项研究的结果可以在空间的不同区域（即泰坦大气的上部区域，彗星彗星和地球电离层等）和实验室（即等离子处理反应堆和中性束源等）的有用了解。血浆。