Field dipolarization in Saturn's magnetotail with planetward ion flows and energetic particle flow bursts: Evidence of quasi-steady reconnection
Author(s)
Type
Journal Article
Abstract
We present a case study of an event from 20 August (day 232) of 2006, when the Cassini spacecraft was sampling the region near 32 RS and 22 h LT in Saturn's magnetotail. Cassini observed a strong northward-to-southward turning of the magnetic field, which is interpreted as the signature of dipolarization of the field as seen by the spacecraft planetward of the reconnection X line. This event was accompanied by very rapid (up to ~1500 km s−1) thermal plasma flow toward the planet. At energies above 28 keV, energetic hydrogen and oxygen ion flow bursts were observed to stream planetward from a reconnection site downtail of the spacecraft. Meanwhile, a strong field-aligned beam of energetic hydrogen was also observed to stream tailward, likely from an ionospheric source. Saturn kilometric radiation emissions were stimulated shortly after the observation of the dipolarization. We discuss the field, plasma, energetic particle, and radio observations in the context of the impact this reconnection event had on global magnetospheric dynamics.
Date Issued
2015-04-07
Date Acceptance
2015-04-01
Citation
Journal of Geophysical Research: Space Physics, 2015, 120 (5), pp.3603-3617
ISSN
2169-9402
Publisher
American Geophysical Union
Start Page
3603
End Page
3617
Journal / Book Title
Journal of Geophysical Research: Space Physics
Volume
120
Issue
5
Copyright Statement
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.
License URL
Sponsor
Science and Technology Facilities Council (STFC)
The Royal Society
Science and Technology Facilities Council
Grant Number
ST/K001051/1
RP140004
ST/N002776/1
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
SHEET BOUNDARY-LAYER
PLASMA SHEET
MAGNETIC-FIELD
MAGNETOSPHERIC SUBSTORMS
NIGHTSIDE MAGNETOSPHERE
ALIGNED BEAMS
ELECTRON
DYNAMICS
DISTRIBUTIONS
SPECTROMETER
Saturn
beams
magnetotail
reconnection
Publication Status
Published