Source regions of banded chorus
Article first published online: 5 JUN 2009
Copyright 2009 by the American Geophysical Union.
Geophysical Research Letters
Volume 36, Issue 11, June 2009
How to Cite
2009), Source regions of banded chorus, Geophys. Res. Lett., 36, L11101, doi:10.1029/2009GL037629., , , and (
- Issue published online: 5 JUN 2009
- Article first published online: 5 JUN 2009
- Manuscript Accepted: 29 APR 2009
- Manuscript Revised: 19 APR 2009
- Manuscript Received: 12 FEB 2009
- plasma waves
 ELF/VLF chorus emissions are very intense electromagnetic plasma waves that are naturally and spontaneously excited near the magnetic equatorial plane outside the plasmasphere during periods of magnetic disturbance. These emissions are believed to play an important role in the acceleration of 10 to 100 keV radiation belt electrons to MeV energies during the disturbed time periods. Spacecraft observations near the magnetic equatorial plane in the regions where chorus emissions are generated show that the chorus often appears in two distinct frequency bands, one band below fce/2 and one band above fce/2, where fce is the local electron gyrofrequency. This configuration is known as banded chorus. In the present paper we show that this type of configuration can be readily explained if it is assumed that the chorus is excited in ducts of either enhanced or depleted cold plasma density.