Theory and simulations of relativistic particle motions in a magnetosonic shock wave
نویسنده
چکیده
The motions of relativistic particles in a magnetosonic shock wave propagating obliquely to an external magnetic field are studied. In the zeroth-order theory, particles continue to move nearly parallel to the external magnetic field in the shock transition region, when the shock speed is close to c cos θ, where c is the speed of light and θ is the propagation angle. Perturbations to this zeroth-order motion are also analyzed for positrons and ions. The perturbation frequency of positrons is ω ∼ Ωp0γ and that of ions is ω ∼ Ωi0γ, where Ωp0 and Ωi0 are the non-relativistic gyrofrequencies of positrons and of ions, respectively, and γ is the Lorentz factor. These theoretical predictions are confirmed with numerical simulations.
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