The radiation mechanism of fast radio bursts

TL;DR

This paper proposes that fast radio bursts are generated by undulator radiation from rotating variable stars, explaining their observed frequency drift and pulse broadening as intrinsic effects rather than environmental propagation effects.

Contribution

It introduces a novel explanation for fast radio bursts based on undulator radiation and source motion, challenging the traditional environmental scattering and dispersion models.

Findings

Fast radio bursts can be explained by undulator radiation from rotating stars.

Large dispersion measures may result from source motion, not just environmental effects.

Pulse broadening is attributed to near-field diffraction effects, not scattering.

Abstract

Fast radio bursts are radio transients observed mainly around 1.5 GHz. Their peak frequency decreases at a rate of 100 ~ 500 MHz/s and some of them have a broader pulse with an exponentially decaying tail. Common assumptions for fast radio bursts include a dispersion effect resulting in the peak frequency drifting and a scattering effect resulting in pulse broadening. These assumptions attribute the abnormally large dispersion measure and scattering measure to the environmental medium of the host galaxy. Here we show that the radiation of fast radio bursts can be explained as an undulator radiation and the large dispersion measure can be due to a motion effect mainly from the rotation of the source which is probably variable stars. In our scenario, the pulse broadening is near-field effects and the pulse itself represents a Fresnel diffraction pattern sweeping the observer. Our work is the first analysis of properties of fast radio bursts in the context of a special mechanism of the radiation instead of a special propagation environment of the radiation.