Characterization of Turbulent Fluctuations in the Sub-Alfvénic Solar Wind
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F24%3A10492012" target="_blank" >RIV/00216208:11320/24:10492012 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=81sGoRaagg" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=81sGoRaagg</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.3847/1538-4357/ad34ab" target="_blank" >10.3847/1538-4357/ad34ab</a>
Alternative languages
Result language
angličtina
Original language name
Characterization of Turbulent Fluctuations in the Sub-Alfvénic Solar Wind
Original language description
Parker Solar Probe (PSP) observed sub-Alfv & eacute;nic solar wind intervals during encounters 8-14, and low-frequency magnetohydrodynamic (MHD) turbulence in these regions may differ from that in super-Alfv & eacute;nic wind. We apply a new mode decomposition analysis to the sub-Alfv & eacute;nic flow observed by PSP on 2021 April 28, identifying and characterizing entropy, magnetic islands, forward and backward Alfv & eacute;n waves, including weakly/nonpropagating Alfv & eacute;n vortices, forward and backward fast and slow magnetosonic (MS) modes. Density fluctuations are primarily and almost equally entropy- and backward-propagating slow MS modes. The mode decomposition provides phase information (frequency and wavenumber k) for each mode. Entropy density fluctuations have a wavenumber anisotropy of k(perpendicular to) > k(parallel to), whereas slow-mode density fluctuations have k(perpendicular to) > k(parallel to). Magnetic field fluctuations are primarily magnetic island modes (delta B-i ) with an O(1) smaller contribution from unidirectionally propagating Alfv & eacute;n waves (delta B A+) giving a variance anisotropy of < delta B-i2 > / < delta B-A2 > = 4.1 . Incompressible magnetic fluctuations dominate compressible contributions from fast and slow MS modes. The magnetic island spectrum is Kolmogorov-like k(perpendicular to) - 1.6 in perpendicular wavenumber, and the unidirectional Alfv & eacute;n wave spectra are k parallel to - 1.6 and k(perpendicular to) - 1.5 . Fast MS modes propagate at essentially the Alfv & eacute;n speed with anticorrelated transverse velocity and magnetic field fluctuations and are almost exclusively magnetic due to beta p << 1. Transverse velocity fluctuations are the dominant velocity component in fast MS modes, and longitudinal fluctuations dominate in slow modes. Mode decomposition is an effective tool in identifying the basic building blocks of MHD turbulence and provides detailed phase information about each of the modes.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10305 - Fluids and plasma physics (including surface physics)
Result continuities
Project
<a href="/en/project/GA23-06401S" target="_blank" >GA23-06401S: Where and how the solar wind is accelerated and heated and how these processes affect its evolution?</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2024
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Astrophysical Journal
ISSN
0004-637X
e-ISSN
1538-4357
Volume of the periodical
966
Issue of the periodical within the volume
1
Country of publishing house
US - UNITED STATES
Number of pages
17
Pages from-to
75
UT code for WoS article
001208658700001
EID of the result in the Scopus database
2-s2.0-85191473086