Fresnel drag in a moving magnetized plasma

TL;DR

This paper analytically investigates how uniform motion affects wave refraction and reflection in a magnetized plasma, revealing significant deviations in wave behavior that could impact plasma diagnostics and control.

Contribution

It provides a theoretical analysis of wave refraction and reflection in moving anisotropic media, specifically magnetized plasma, highlighting effects of motion on wave trajectories.

Findings

Motion causes non-negligible deviation of low-frequency X-mode

Asymmetrical total reflection angles are observed due to motion

Magnetic field orientation influences the competition between anisotropy and drag

Abstract

The change in direction of the wavevector and group velocity experienced by a wave refracted at the interface of an anisotropic medium in uniform linear motion are determined analytically. These transmission conditions, which are shown to be consistent with generalized Snell's law written in the laboratory frame, are then used to examine the effect of motion on waves incident on a magnetized plasma. For an incident wave in the plane perpendicular to the magnetic field the motion is observed to lead to non negligible deviation of the low-frequency X-mode, as well as to non-symmetrical total reflection angles. These effects are shown to be further complicated when the magnetic field is in the plane formed by the incident wavevector and the medium's velocity, as the anisotropy now competes with the motion-induced drag. Although obtained in simplified configurations, these results suggest that accounting for motion when modeling plasma waves trajectory could be important under certain conditions, calling for a more detailed quantification of the effect of motion in actual diagnostics and plasma control schemes.