Acceleration of relativistic electrons due to resonant scattering by whistler mode waves generated by temperature anisotropy in the inner magnetosphere

Abstract

Resonant interaction between relativistic electrons and monochromatic whistler mode wave is studied with a self‐consistent simulation model. We treat a monochromatic whistler mode wave excited by an instability associated with a temperature anisotropy of medium‐energy electrons. In the simulation result the monochromatic whistler mode wave traps relativistic electrons which satisfy the resonance condition. Especially, in a case in which oppositely propagating monochromatic waves coexist, we find that a combined effect of wave trapping connects diffusion curves and opens a route for the rapid acceleration. The motion of the trapped relativistic electrons in the momentum space is estimated from the intersection of resonance curves and the scale of trapping region which is determined by both the trapping velocity and the resonance velocity. The present simulation reveals that selected resonant electrons are effectively accelerated in a homogeneous system where both forward and backward traveling waves interact with the relativistic electrons.