A model of so-called `Zebra' emissions in type IV radio bursts

TL;DR

This paper proposes a new model explaining Zebra pattern emissions in type IV radio bursts, involving ion-ring distributions and ion-cyclotron maser interactions that produce modulated electromagnetic harmonics.

Contribution

It introduces a novel mechanism linking ion-ring distributions and ion-cyclotron maser effects to Zebra pattern emissions in solar radio bursts.

Findings

The model explains the quasi-periodic switching and amplification of emissions.

It accounts for the modulation of electron maser emission by ion-cyclotron harmonics.

The mechanism aligns with observed features of Zebra patterns in type IV bursts.

Abstract

A simple mechanism for the generation of electromagnetic Zebra pattern emission is proposed. The mechanism is based on the generation of an ion-ring distribution in a magnetic mirror geometry in the presence of a properly directed field-aligned electric potential field. The ion-cyclotron maser then generates a number of electromagnetic ion-cyclotron harmonics which modulate the electron maser emission. The mechanism is capable of switching the emission on and off or amplifying it quasi-periodically which is a main feature of the observations.