Anti-sunward high-speed jets in the subsolar magnetosheath
Item
Title (Dublin Core)
Anti-sunward high-speed jets in the subsolar magnetosheath
Description (Dublin Core)
Using 2008–2011 data from the five Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft in Earth's subsolar
magnetosheath, we study high-speed jets identified as intervals when the
anti-sunward component of the dynamic pressure in the subsolar magnetosheath exceeds half of its
upstream solar wind value. Based on our comprehensive data set of 2859
high-speed jets, we obtain the following statistical results on jet properties
and favorable conditions: high-speed jets occur predominantly downstream of
the quasi-parallel bow shock, i.e., when interplanetary magnetic field cone
angles are low. Apart from that, jet occurrence is only very weakly dependent
(if at all) on other upstream conditions or solar wind variability. Typical
durations and recurrence times of high-speed jets are on the order of tens of
seconds and a few minutes, respectively. Relative to the ambient
magnetosheath, high-speed jets exhibit higher speed, density and magnetic
field intensity, but lower and more isotropic temperatures. They are
almost always super-Alfvénic, often even super-magnetosonic, and
typically feature 6.5 times as much dynamic pressure and twice as much total
pressure in anti-sunward direction as the surrounding plasma does. Consequently,
they are likely to have significant effects on the magnetosphere and
ionosphere if they impinge on the magnetopause.
magnetosheath, we study high-speed jets identified as intervals when the
anti-sunward component of the dynamic pressure in the subsolar magnetosheath exceeds half of its
upstream solar wind value. Based on our comprehensive data set of 2859
high-speed jets, we obtain the following statistical results on jet properties
and favorable conditions: high-speed jets occur predominantly downstream of
the quasi-parallel bow shock, i.e., when interplanetary magnetic field cone
angles are low. Apart from that, jet occurrence is only very weakly dependent
(if at all) on other upstream conditions or solar wind variability. Typical
durations and recurrence times of high-speed jets are on the order of tens of
seconds and a few minutes, respectively. Relative to the ambient
magnetosheath, high-speed jets exhibit higher speed, density and magnetic
field intensity, but lower and more isotropic temperatures. They are
almost always super-Alfvénic, often even super-magnetosonic, and
typically feature 6.5 times as much dynamic pressure and twice as much total
pressure in anti-sunward direction as the surrounding plasma does. Consequently,
they are likely to have significant effects on the magnetosphere and
ionosphere if they impinge on the magnetopause.
Creator (Dublin Core)
F. Plaschke
H. Hietala
V. Angelopoulos
Subject (Dublin Core)
Science
Q
Physics
QC1-999
Geophysics. Cosmic physics
QC801-809
Publisher (Dublin Core)
Copernicus Publications
Date (Dublin Core)
2013-10-01T00:00:00Z
Type (Dublin Core)
article
Identifier (Dublin Core)
10.5194/angeo-31-1877-2013
0992-7689
1432-0576
https://doaj.org/article/3d29b0f4535c4f16947413b1ace998a9
Source (Dublin Core)
Annales Geophysicae, Vol 31, Pp 1877-1889 (2013)
Language (Dublin Core)
EN
Relation (Dublin Core)
https://www.ann-geophys.net/31/1877/2013/angeo-31-1877-2013.pdf
https://doaj.org/toc/0992-7689
https://doaj.org/toc/1432-0576
Provenance (Dublin Core)
Journal Licence: CC BY