A mechanistic interpretation of the resonant wave-particle interaction

This paper provides a simple mechanistic interpretation of the resonant wave-particle interaction of Landau. For the simple case of a Langmuir wave in a Vlasov plasma, the non-resonant electrons satisfy an oscillator equation that is driven resonantly by the bare electric field from the resonant electrons, and in the case of wave damping, this complex driver field is of a phase to reduce the oscillation amplitude. The wave-particle resonant interaction also occurs in waves governed by 2D E x B drift dynamics, such as a diocotron wave. In this case, the bare electric field from the resonant electrons causes E x B drift motion back in the core plasma, reducing the amplitude of the wave. Published by AIP Publishing.