This work investigates the basic features of Nonlinear Ion Acoustic Solitary waves (NIASWs) and their dynamical behaviours in an unmagnetized relativistic collisionless plasma system via the Schamel Korteweg-de Vries (SKdV) equation. Such plasma is composed by the generalized distributed electrons, Boltzmann distributed positrons and relativistic warm ions. The influences of plasma parameters on NIASWs and their dynamical behaviours are investigated by comparing 26−term expansion of relativistic Lorentz factor (RLF) with both of weakly (2−term expansion of RLF) and highly (3−term expansion of RLF) regimes. It is found that the 26−term expansion of RLF are significantly changed NIASWs instead of both weakly and highly relativistic regimes. Therefore, the theoretical results would be very useful for understanding the nature (amplitude, width, polarity, etc.) of wave dynamics not only in astrophysical and space environments but also in further laboratory studies, where the proposed plasma assumptions are existed.

中文翻译：

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相对论等离子体中具有动力学行为的非线性离子声孤立波

这项工作通过 Schamel Korteweg-de Vries (SKdV) 方程研究了非线性离子声孤立波 (NIASW) 的基本特征及其在未磁化相对论性无碰撞等离子体系统中的动力学行为。这种等离子体由广义分布电子、玻尔兹曼分布正电子和相对论暖离子组成。通过比较相对论洛伦兹因子 (RLF) 的 26 项扩展与弱（RLF 的 2 项扩展）和高（RLF 的 3 项扩展）机制，研究等离子体参数对 NIASW 及其动力学行为的影响。结果发现，RLF 的 26 项扩张显着改变了 NIASWs，而不是弱相对论和高度相对论制度。因此，理论结果对于理解性质（幅度、宽度、