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arXiv · 2111.07826

The Interplay of Regularizing Factors in the Model of Upper Hybrid Oscillations of Cold Plasma

Maria I. Delova·Olga S. Rozanova
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Abstract

A one-dimensional nonlinear model of the so-called upper hybrid oscillations in a magnetoactive plasma is investigated taking into account electron-ion collisions. It is known that both the presence of an external magnetic field of strength $ B_0 $ and a sufficiently large collisional factor $ \nu $ help suppress the formation of a finite-dimensional singularity in a solution (breaking of oscillations). Nevertheless, the suppression mechanism is different: an external magnetic field increases the oscillation frequency, and collisions tend to stabilize the medium and suppress oscillations. In terms of the initial data and the coefficients $ B_0 $ and $ \nu $, we establish a criterion for maintaining the global smoothness of the solution. Namely, for fixed $ B_0 $ and $ \nu \ge 0 $ one can precisely divide the initial data into two classes: one leads to stabilization to the equilibrium and the other leads to the destruction of the solution in a finite time. Next, we examine the nature of the stabilization. We show that for small $ B_0 $ an increase in the intensity factor first leads to a change in the oscillatory behavior of the solution to monotonic damping, which is then again replaced by oscillatory damping. At large values of $ B_0 $, the solution is characterized by oscillatory damping regardless of the value of the intensity factor $ \nu $.

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Maria I. Delova, Olga S. Rozanova. 2021-11-15. The Interplay of Regularizing Factors in the Model of Upper Hybrid Oscillations of Cold Plasma. https://arxiv.org/abs/2111.07826

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