# Fast radio burst source properties and curvature radiation model

## TL;DR

This paper proposes a model for FRB sources based on strong magnetic fields and curvature radiation, suggesting magnetars as the origin and predicting high-frequency counterparts.

## Contribution

It introduces a curvature radiation model for FRBs requiring ultra-strong magnetic fields and predicts observable high-frequency FRB-like bursts.

## Key findings

- Magnetic field in FRB sources should be at least 10^{14} Gauss.
- FRBs likely originate near magnetar surfaces via magnetic reconnection.
- Predicted high-frequency FRB-like bursts could occur up to optical frequencies.

## Abstract

We use the observed properties of fast radio bursts (FRBs) and a number of general physical considerations to provide a broad-brush model for the physical properties of FRB sources and the radiation mechanism. We show that the magnetic field in the source region should be at least 10^{14} Gauss. This strong field is required to ensure that the electrons have sufficiently high ground state Landau energy so that particle collisions, instabilities, and strong electric and magnetic fields associated with the FRB radiation do not perturb electrons' motion in the direction transverse to the magnetic field and destroy their coherent motion; coherence is required by the high observed brightness temperature of FRB radiation. The electric field in the source region required to sustain particle motion for a wave period is estimated to be of order 10^{11} esu. These requirements suggest that FRBs are produced near the surface of magnetars perhaps via forced reconnection of magnetic fields to produce episodic, repeated, outbursts. The beaming-corrected energy release in these bursts is estimated to be ~10^{36} ergs, whereas the total energy in the magnetic field is at least ~10^{45} ergs. We provide a number of predictions for this model which can be tested by future observations. One of which is that short duration FRB-like bursts should exist at much higher frequencies, possibly up to optical.