In this article we study nonlinear waves in Hall plasmas. We consider magnetosonic waves propagating at the angles with respect to the equilibrium magnetic field that are not close to either 0 or π /2. Using the reductive perturbation method we derive the three-dimensional Kadomtsev-Petviashvili (KP) equation. We use the KP equation to show that both fast and slow magnetosonic solitons are unstable with respect to transverse perturbations. We confront our results with the investigation of soliton stability in anisotropic media using the study of soliton self-refraction.

中文翻译：

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霍尔等离子体中的磁声波和孤子稳定性的Kadomtsev-Petviashvili方程

在本文中，我们研究霍尔等离子体中的非线性波。我们考虑以相对于平衡磁场不接近0或π/ 2的角度传播的磁声波。使用还原摄动法，我们导出了三维Kadomtsev-Petviashvili（KP）方程。我们使用KP方程表明，相对于横向扰动，快磁孤子和慢磁孤子都是不稳定的。我们用孤子自折射的研究来研究各向异性介质中孤子的稳定性。