Short, large-amplitude speed enhancements in the near-Sun fast solar wind
File(s)sty953.pdf (2.29 MB)
Published version
Author(s)
Horbury, TS
Matteini, Lorenzo
Stansby, David
Type
Journal Article
Abstract
We report the presence of intermittent, short discrete enhancements in plasma speed in the near-Sun high speed solar wind. Lasting tens of seconds to minutes in spacecraft measurements at 0.3 AU, speeds inside these enhancements can reach 1000 km/s, corresponding to a kinetic energy up to twice that of the bulk high speed solar wind. These events, which occur around 5% of the time, are Alfvenic in nature with large magnetic field deflections and are the same temperature as the surrounding plasma, in contrast to the bulk fast wind which has a well-established positive speed-temperature correlation. The origin of these speed enhancements is unclear but they may be signatures of discrete jets associated with transient events in the chromosphere or corona. Such large short velocity changes represent a measurement and analysis challenge for the upcoming Parker Solar Probe and Solar Orbiter missions.
Date Issued
2018-08
Date Acceptance
2018-04-11
Citation
Monthly Notices of the Royal Astronomical Society, 2018, 478 (2), pp.1980-1986
ISSN
0035-8711
Publisher
Oxford University Press (OUP)
Start Page
1980
End Page
1986
Journal / Book Title
Monthly Notices of the Royal Astronomical Society
Volume
478
Issue
2
Copyright Statement
© 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This is a pre-copy-editing, author-produced version of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The definitive publisher-authenticated version T S Horbury, L Matteini, D Stansby, Short, large-amplitude speed enhancements in the near-Sunfast solar wind, Monthly Notices of the Royal Astronomical Society, Volume 478, Issue 2, August 2018, Pages 1980–1986, is available online at: https://doi.org/10.1093/mnras/sty953
Sponsor
Science and Technology Facilities Council (STFC)
Identifier
https://academic.oup.com/mnras/article/478/2/1980/4987231
Grant Number
ST/N000692/1
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
Sun: corona
solar wind
MAGNETIC-FIELD
RADIAL EVOLUTION
TURBULENCE
FLUCTUATIONS
Astronomy & Astrophysics
0201 Astronomical and Space Sciences
Publication Status
Published
Date Publish Online
2018-04-26