Ion-acoustic solitons oblique collisions in a magnetized ultra-relativistic degenerate plasma at critical compositions and nonzero temperatures

Abstract

The mechanism of ion-acoustic (IA) soliton oblique collisions is examined at nonzero temperatures and critical compositions in a magnetized ultra-relativistic degenerate plasma using the extended Poincaré–Lighthill–Kuo (EPLK) method. Two conditions, referred to as the generic and critical cases, are obtained. Korteweg-de Vries (KdV) equations that govern the excitation of IA solitons and their phase shifts have been derived for the generic case. At a critical composition, modified KdV (mKdV) equations describe the nonlinear propagation of IA solitons, and thus the corresponding phase shifts are deduced. Furthermore, for an in-depth investigation, we examined the collision of two IA solitons of the same polarity and opposite polarities arising from oblique collisions at discrete times. In these two situations, the phase shifts of IA solitons due to the oblique collisions increase with an increase in the collision angle. The phase shift curve reaches its maximum value at the perpendicular collision. This work may aid in interpreting the features of IA solitons in a degenerate plasma, such as white dwarfs, that support soliton propagation.