Nonlinear solitary waves are investigated for a plasma system at the night side of Titan's ionosphere. The plasma model consists of three positive ions, namely C2H, HCNH+, and C3H, as well as Maxwellian electrons. The basic set of fluid equations is reduced to a Korteweg de-Vries (KdV) equation and linear inhomogeneous higher order KdV (LIHO-KdV) equation. The solitary wave solutions of both equations are obtained using a renormalization method. The solitary waves' existence region and the wave profile are investigated, and their dependences on the plasma parameters at the night side of Titan's ionosphere are examined. The solitary waves' phase velocities are subsonic or supersonic, and the propagating pulses are usually positive. The effect of higher-order corrections on the perturbation theory is investigated. It is found that the higher-order contribution makes the amplitude slightly taller, which is suitable for describing the solitary waves when the amplitude augments.

中文翻译：

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泰坦电离层夜侧的离子​​声波：高阶近似

研究了泰坦电离层夜间等离子体系统的非线性孤立波。等离子体模型包含三个正离子，即 C2H、HCNH+ 和 C3H，以及麦克斯韦电子。基本的流体方程组被简化为 Korteweg de-Vries (KdV) 方程和线性非齐次高阶 KdV (LIHO-KdV) 方程。两个方程的孤立波解都是使用重整化方法获得的。研究了孤立波的存在区域和波廓，并研究了它们对泰坦电离层夜间等离子体参数的依赖性。孤立波的相速度为亚音速或超音速，传播脉冲通常为正。研究了高阶修正对微扰理论的影响。