A Unified Geometric Model of Repeating and Non-Repeating Fast Radio Bursts

TL;DR

This paper introduces a unified geometric model based on magnetospheric effects to explain the differences between repeating and non-repeating fast radio bursts, linking their properties to the impact angle of emission regions.

Contribution

It proposes a novel geometric framework that unifies the understanding of FRB repeaters and non-repeaters through magnetospheric propagation effects, supported by polarization and other observational properties.

Findings

The model explains polarization differences between repeaters and non-repeaters.

It accounts for various observational features like bandwidth, duration, and luminosity.

Supports a magnetospheric origin for FRBs.

Abstract

Fast radio bursts (FRBs) are millisecond-duration extragalactic radio transients. They apparently fall into repeaters and non-repeaters. However, such a classification has lacked a motivation on the physical picture. Here we propose a unified geometric model to distinguish between the repeaters and non-repeaters, in which the quasi-tangential (QT) propagation effect within the magnetospheric polar cap of a neutron star is considered. In this model, the non-repeaters arise from the sources whose emitting region has a smaller impact angle with respect to the magnetic axis, while the repeaters come from the sources whose emitting region has a larger impact angle. The observational discriminant polarization properties between the repeaters and non-repeaters are an important clue to verifying this unified geometric model since the polarization is sensitive to the QT propagation effect. Moreover, our model effectively explains all of the other discriminant properties, including bandwidth, duration, peak luminosity, energy, brightness temperature, time-frequency downward drifting, and repetition rate, providing compelling evidence for the magnetospheric origin of FRBs.