Nonlinear interaction of obliquely propagating Bernstein waves with electrons in a plasma

We obtain analytical expression for the interaction of obliquely propagating Bernstein waves with electrons by using the monochromatic wave approximation for quasi-linear theory in a weakly turbulent plasma. A numerical analysis is also carried out. The waves show initially strong damping and irregular amplitude oscillation, and the electron velocity distribution shows a variation corresponding to one of the waves. These are results of the energy exchange between waves and electrons. Despite the use of the monochromatic wave approximation, strongly scattering electrons with a broad velocity spread about the resonant velocity by the wave is seen.