Discovery of Alfvén waves planetward of Saturn's rings
Date
10/02/2021Metadata
Show full item recordAbstract
Between April and September 2017 in the final stages of the Cassini Saturn Orbiter mission the spacecraft executed 22 orbits passing planetward of the innermost ring, the D ring. During all periapsis passes oscillations were detected in the azimuthal magnetic field components on typical time scales of a few minutes. We argue that these time varying magnetic signals detected on the spacecraft are also primarily time varying in the plasma frame. Furthermore, we show that nearly all signals exhibit a spatial feature, namely a magnetic node near the effective field line equator. We propose that the oscillations are associated with Alfvén waves excited in local field line resonances, most likely driven from global sources.
Citation
Southwood , D J , Cao , H , Shebanits , O , Elsden , T , Hunt , G J & Dougherty , M K 2021 , ' Discovery of Alfvén waves planetward of Saturn's rings ' , Journal of Geophysical Research: Space Physics , vol. 126 , no. 2 , e2020JA028473 . https://doi.org/10.1029/2020JA028473
Publication
Journal of Geophysical Research: Space Physics
Status
Peer reviewed
ISSN
2169-9402Type
Journal article
Rights
Copyright © 2020. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Description
Funding: Work at Imperial College was supported by UKRI/STFC grants ST/N000692/1 and ST/S000364/1. T. Elsden was funded by a Leverhulme Early Career Fellowship, split jointly by the Leverhulme Trust (ECF-2019-155) and the University of Leicester.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.