Plasmaspheric hiss amplification mechanisms identified
Article first published online: 7 SEP 2012
©2012. American Geophysical Union. All Rights Reserved.
Eos, Transactions American Geophysical Union
Volume 93, Issue 37, page 360, 11 September 2012
How to Cite
2012), Plasmaspheric hiss amplification mechanisms identified, Eos Trans. AGU, 93(37), 360., (
- Issue published online: 7 SEP 2012
- Article first published online: 7 SEP 2012
- Cited By
- plasma density structure;
- plasma wave instability;
- plasmaspheric hiss;
- ray tracing
Over the past 3 decades the hypothesis that chorus waves—a form of highintensity plasma wave often found in the outer magnetosphere—evolve into plasmaspheric hiss in the plasmasphere has grown in prominence. Plasmaspheric hiss is a form of low-frequency radio wave that is often observed in the regions within the plasmasphere that have high plasma densities. Plasmaspheric hiss is important in that the hiss waves interact with highenergy electrons in Earth's geomagnetic field, carving out a swath between the inner and outer Van Allen radiation belts to form the “slot region,” a relative safe zone with minimized radiation hazard. Though modeled simulations of plasmaspheric hiss formation from chorus waves have been able to reproduce the major properties of observed hiss, they often underestimate hiss intensity by 10–20 decibels. Drawing on observations from the planet's dayside made using NASA's Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellite, Chen et al. examine two mechanisms that could make up for this shortfall.