Solitary waves in a cometary plasma with heavy dust ion pairs

Multicomponent plasma in an astrophysical environment comprising wind electrons, cometary electrons, positive and negative dust ions, and lighter hydrogen ions was studied earlier by a pseudo-potential approach. The coma of comet Halley is reported to comprise many heavier positive and negative ions. Thus, we generalize the soliton solution for a plasma consisting of multiple pair-ion dust species. Heavier atomic and molecular ions are considered as dust ions in this model. The lighter ions and electrons are modeled by Kappa distribution. We find that the presence of multiple dust pair ions enhances soliton amplitude. The effect of the temperature and density of lighter ions gives insight into the switching of compressive and rarefractive nature of the solutions. The compressive and rarefractive regimes of these solitary waves are analyzed and reported for the first time.