Face-to-Face Collisions of Bright and Dark Ion Acoustic Solitons in Superthermal Electrons for Different Geometrical Configurations

Abstract

Abstract The face-to-face collision of ion acoustic solitons (IASs) in superthermal plasmas composed of positive and negative ion fluids and superthermal electrons is investigated for different geometrical configurations. For the generic case, the extended Poincaré-Lighthill-Kuo (EPLK) analysis is employed to obtain the extended Korteweg-de Vries (EKdV) equations and phase shift equations. The non-linear propagation and the face-to-face collision of bright and dark IASs are studied. In addition, when the concentration of ion reaches the critical value, the EPLK method is applied to obtain the modified Korteweg-de Vries (mKdV) equations and the phase shift relations, which govern the excitation and the face-to-face collision of bright and dark IASs. Appropriately, the effects of several parameters such as the electron concentration, the superthermality of electrons and the diversity in the system’s geometry under consideration on the trajectories of IASs after the collision are discussed. Numerical calculations lead to some highlights on the properties of bright and dark IASs (e.g. in laboratory plasmas such as laser–matter/plasma interaction experiments and in astrophysical environments such as lower part of magnetosphere).