Global model of low‐frequency chorus (fLHR<ffce) from multiple satellite observations
Open Access
- 9 January 2014
- journal article
- research article
- Published by American Geophysical Union (AGU) in Geophysical Research Letters
- Vol. 41 (2) , 280-286
Abstract
Whistler mode chorus is an important magnetospheric emission, playing a dual role in the acceleration and loss of relativistic electrons in the Earth's outer radiation belt. Chorus is typically generated in the equatorial region in the frequency range 0.1–0.8 fce, where fce is the local electron gyrofrequency. However, as the waves propagate to higher latitudes, significant wave power can occur at frequencies below 0.1fce. Since this wave power is largely omitted in current radiation belt models, we construct a global model of low‐frequency chorus, fLHR<ffce, using data from six satellites. We find that low‐frequency chorus is strongest, with an average intensity of 200 pT2, in the prenoon sector during active conditions at midlatitudes (20°<|λm|L∗<8. Such midlatitude, low‐frequency chorus wave power will contribute to the acceleration and loss of relativistic electrons and should be taken into account in radiation belt models.Keywords
This publication has 26 references indexed in Scilit:
- Statistics of whistler mode waves in the outer radiation belt: Cluster STAFF‐SA measurementsJournal of Geophysical Research: Space Physics, 2013
- Off‐equatorial chorus occurrence and wave amplitude distributions as observed by the Polar Plasma Wave InstrumentJournal of Geophysical Research, 2012
- Three‐dimensional diffusion simulation of outer radiation belt electrons during the 9 October 1990 magnetic stormJournal of Geophysical Research, 2009
- The unexpected origin of plasmaspheric hiss from discrete chorus emissionsNature, 2008
- Radiation Belt Environment model: Application to space weather nowcastingJournal of Geophysical Research, 2008
- The dual role of ELF/VLF chorus waves in the acceleration and precipitation of radiation belt electronsJournal of Atmospheric and Solar-Terrestrial Physics, 2007
- Simulation of the outer radiation belt electrons near geosynchronous orbit including both radial diffusion and resonant interaction with Whistler‐mode chorus wavesGeophysical Research Letters, 2005
- Timescale for radiation belt electron acceleration by whistler mode chorus wavesJournal of Geophysical Research, 2005
- Energization of relativistic electrons in the presence of ULF power and MeV microbursts: Evidence for dual ULF and VLF accelerationJournal of Geophysical Research, 2003
- Postmidnight chorus: A substorm phenomenonJournal of Geophysical Research, 1974