Characterization of the Transmission and Generation of Turbulence at Interplanetary Shocks

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10510542" target="_blank" >RIV/00216208:11320/25:10510542 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6WH8giuFYi" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=6WH8giuFYi</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-4357/adeb86" target="_blank" >10.3847/1538-4357/adeb86</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Characterization of the Transmission and Generation of Turbulence at Interplanetary Shocks

Popis výsledku v původním jazyce

We study the transmission and characteristics of turbulent magnetohydrodynamic (MHD) fluctuations from upstream to downstream regions of interplanetary (IP) shocks using the linear mode decomposition (LMD) technique of G. P. Zank et al. We perform a superposed epoch analysis (SEA) of 84 fast-forward quasi-perpendicular shock events observed by the Wind spacecraft at 1 au. We find that the intensities of various MHD modes associated with density, velocity, and magnetic field fluctuations are enhanced by similar to 4-14 times across the shock. On average, the amplitude enhancement of velocity fluctuations across the shock is smaller than that of density and magnetic fluctuations. The frequency spectra reveal that the entropy, magnetic island, and Alfven modes are the dominant contributors to the overall density, magnetic field, and velocity fluctuations, respectively, both upstream and downstream. The SEA reveals that the downstream spectral slope of various modes closely follows a f(-5/3) (or k(-5/3)) power law, but the upstream spectra are slightly flatter than the downstream curves. A steeper spectral slope downstream suggests an increased energy dissipation or a stronger turbulent cascade. These findings show the usefulness of the LMD technique to decompose turbulent fluctuations into fundamental linear MHD modes, providing a deeper understanding of turbulence upstream and downstream of IP shocks.

Název v anglickém jazyce

Characterization of the Transmission and Generation of Turbulence at Interplanetary Shocks

Popis výsledku anglicky

We study the transmission and characteristics of turbulent magnetohydrodynamic (MHD) fluctuations from upstream to downstream regions of interplanetary (IP) shocks using the linear mode decomposition (LMD) technique of G. P. Zank et al. We perform a superposed epoch analysis (SEA) of 84 fast-forward quasi-perpendicular shock events observed by the Wind spacecraft at 1 au. We find that the intensities of various MHD modes associated with density, velocity, and magnetic field fluctuations are enhanced by similar to 4-14 times across the shock. On average, the amplitude enhancement of velocity fluctuations across the shock is smaller than that of density and magnetic fluctuations. The frequency spectra reveal that the entropy, magnetic island, and Alfven modes are the dominant contributors to the overall density, magnetic field, and velocity fluctuations, respectively, both upstream and downstream. The SEA reveals that the downstream spectral slope of various modes closely follows a f(-5/3) (or k(-5/3)) power law, but the upstream spectra are slightly flatter than the downstream curves. A steeper spectral slope downstream suggests an increased energy dissipation or a stronger turbulent cascade. These findings show the usefulness of the LMD technique to decompose turbulent fluctuations into fundamental linear MHD modes, providing a deeper understanding of turbulence upstream and downstream of IP shocks.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astrophysical Journal

ISSN

0004-637X

e-ISSN

1538-4357

Svazek periodika

989

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

19

Strana od-do

82

Kód UT WoS článku

001546291700001

EID výsledku v databázi Scopus

2-s2.0-105012558538