On the Breaking of a Slow Extraordinary Wave in a Cold Magnetoactive Plasma

The effect of an external magnetic field on plane relativistic nonlinear oscillations and waves is investigated. To initialize a slow extraordinary (SE) wave in a magnetoactive plasma, we use a method for constructing the missing initial conditions based on solving a linear problem by the Fourier method. For the purpose of numerical simulation of a nonlinear wave, a scheme of the second-order finite difference method of the MacCormack type is constructed. It is shown that when the external magnetic field is taken into account, the Langmuir oscillations are transformed into an SE wave. In this case, the wave’s speed increases with an increase in the external constant field, which contributes to the removal of energy from the initial region of the oscillations' localization. For this reason, starting from a certain critical value of the external field, the breaking effect ceases to be observed; i.e., a smooth solution that is global in time is formed.