The electron-ion-positively charged dust plasma system containing Boltzmann distributed electron species, cold inertial ion species, and stationary positively charged dust (pcd) species are considered. The roles of pcd species in the formation of ion-acoustic (IA) subsonic solitary waves (SWs) are investigated by the pseudo-potential approach, which is valid for arbitrary amplitude time-independent subsonic SWs, as well as by the reductive perturbation method, which is valid for the time-dependent small amplitude subsonic SWs. It is observed that the presence of the pcd species reduces the phase speed of the IA waves, and consequently supports the IA subsonic SWs with the positive wave potential in such electron-ion-pcd plasmas. This is due to the reduction of the space charge electric field by the presence of the pcd species. The applications of the work in space environments (viz. Earth's mesosphere, cometary tails, Jupiter's magnetosphere, etc.), where pcd species have been detected, are briefly discussed.

中文翻译：

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带正电尘埃在电子-离子带正电尘埃等离子体中离子-声亚音速孤立波形成中的作用

考虑了包含玻尔兹曼分布电子种类、冷惯性离子种类和静止带正电尘埃 (pcd) 种类的电子-离子带正电尘埃等离子体系统。通过赝势方法研究了 pcd 物质在离子声 (IA) 亚音速孤立波 (SW) 形成中的作用，该方法适用于任意振幅时间无关的亚音速 SW，以及还原扰动方法，这对于瞬态小振幅亚音速 SW 有效。据观察，pcd 物质的存在降低了 IA 波的相位速度，因此支持 IA 亚音速 SW 在这种电子-离子-pcd 等离子体中具有正波势。这是由于 PCD 物种的存在降低了空间电荷电场。