Nonlinear scattering of Fast Radio Bursts

Abstract

Nonlinear radio waves modulate the plasma, scatter on the modulations, and develop an intermittent power spectrum -- perhaps. Rudiments of theory, numerical simulations, and qualitative modeling of nonlinear scattering are presented. Nonlinear radio waves in electron-positron plasma are shown to be unstable, the instability growth rate is calculated. The long-term outcome of the instability is studied numerically; an intermittent power spectrum is found. The frequency coherence scale of the intermittent power spectrum is interpreted as a measure of the nonlinear scattering screen.