Damping of Large-Amplitude Plasma Waves Propagating Perpendicular to the Magnetic Field

Computer simulations of magnetosonic waves, velocity-shell instabilities, and upper-hybrid heating show evidence of a general damping mechanism for large-amplitude electrostatic waves propagating perpendicular to a magnetic field: Particles trapped by a wave of frequency ω and phase velocity Vₚₕ see an electric field Vₚₕ×B, which accelerates them parallel to the wave front until the v×B force is large enough for detrapping. For ωωc, velocities as large as (ω4ωc)Vₚₕ can be attained, within a time ωct≈ω4ωc.