A simple mechanism for the generation of elec- tromagnetic “Zebra” pattern emissions is proposed. “Zebra” bursts are regularly spaced narrow-band radio emissions on the otherwise broadband radio continuum emitted by the ac- tive solar corona. 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 po- tential field. Such ion-rings or ion-conics are well known from magnetospheric observations. Under coronal condi- tions they may become weakly relativistic. In this case the ion-cyclotron maser generates a number of electromagnetic ion-cyclotron harmonics which modulate the electron maser emission. The mechanism is capable of switching the emis- sion on and off or amplifying it quasi-periodically which is a main feature of the observations.
Treumann, R. A.; Nakamura, R.; and Baumjohann, W., "A Model of So-Called "Zebra" Emissions in Solar Flare Radio Burst Continua" (2011). Open Dartmouth: Faculty Open Access Articles. 2502.