Journal article
Formation of electron radiation belts at Saturn by Z-mode wave acceleration
Nature communications, Vol.9(1), pp.5062-7
11/29/2018
DOI: 10.1038/s41467-018-07549-4
PMCID: PMC6265320
PMID: 30498204
Abstract
At Saturn electrons are trapped in the planet's magnetic field and accelerated to relativistic energies to form the radiation belts, but how this dramatic increase in electron energy occurs is still unknown. Until now the mechanism of radial diffusion has been assumed but we show here that in-situ acceleration through wave particle interactions, which initial studies dismissed as ineffectual at Saturn, is in fact a vital part of the energetic particle dynamics there. We present evidence from numerical simulations based on Cassini spacecraft data that a particular plasma wave, known as Z-mode, accelerates electrons to MeV energies inside 4 R
(1 R
= 60,330 km) through a Doppler shifted cyclotron resonant interaction. Our results show that the Z-mode waves observed are not oblique as previously assumed and are much better accelerators than O-mode waves, resulting in an electron energy spectrum that closely approaches observed values without any transport effects included.
Details
- Title: Subtitle
- Formation of electron radiation belts at Saturn by Z-mode wave acceleration
- Creators
- E E Woodfield - British Antarctic SurveyR B Horne - British Antarctic SurveyS A Glauert - British Antarctic SurveyJ D Menietti - University of IowaY Y Shprits - GFZ Helmholtz Centre for GeosciencesW S Kurth - University of Iowa
- Resource Type
- Journal article
- Publication Details
- Nature communications, Vol.9(1), pp.5062-7
- DOI
- 10.1038/s41467-018-07549-4
- PMID
- 30498204
- PMCID
- PMC6265320
- NLM abbreviation
- Nat Commun
- ISSN
- 2041-1723
- eISSN
- 2041-1723
- Language
- English
- Date published
- 11/29/2018
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984455555102771
Metrics
3 Record Views