Nonlinear ion acoustic ring solitons in a multicomponent plasma with superthermal electrons: Propagation and collision

Abstract

In this paper, the propagation and the collision of ion acoustic ring solitons (IARSs) in a multicomponent plasma with superthermal electrons are theoretically investigated by employing an extended Poincaré–Lighthill–Kuo method. For the generic case, the dynamics and collisions of IARSs are studied via cylindrical Korteweg-de Vries (cKdV) equations and phase shift equations. It is found physically that both positive and negative polarity IARSs can propagate and collide, which usually leads to a time delay in propagation occurring during the collision, as compared to a single ion acoustic soliton (IARS) without collisions in the same physical model. Moreover, at a critical value of the negative ion-to-positive ion concentration, modified cylindrical Korteweg-de Vries (mcKdV) equations and their corresponding phase shifts have been derived. In general, it is observed that the trajectories of IARSs after collisions are significantly modified due to the influence of negative ion-to-positive ion density ratio, negative ion-to-positive ion mass ratio, the superthermal electron parameter, and the positions of IARSs. The numerical results are applied to the Earth's ionosphere, such as the D and F regions. The present investigation will be helpful in understanding the properties of the Earth's ionosphere containing positive and negative ions with superthermal electrons.