Articles | Volume 29, issue 9
https://doi.org/10.5194/angeo-29-1673-2011
https://doi.org/10.5194/angeo-29-1673-2011
Regular paper
 | 
29 Sep 2011
Regular paper |  | 29 Sep 2011

A model of so-called "Zebra" emissions in solar flare radio burst continua

R. A. Treumann, R. Nakamura, and W. Baumjohann

Abstract. A simple mechanism for the generation of electromagnetic "Zebra" pattern emissions is proposed. "Zebra" bursts are regularly spaced narrow-band radio emissions on the otherwise broadband radio continuum emitted by the active 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 potential field. Such ion-rings or ion-conics are well known from magnetospheric observations. Under coronal conditions 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 emission on and off or amplifying it quasi-periodically which is a main feature of the observations.

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