Properties of Magnetic Field Fluctuations in Long-Lasting Radial IMF Events from Wind Observation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F22%3A10456478" target="_blank" >RIV/00216208:11320/22:10456478 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=bu0gn.zvUP" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=bu0gn.zvUP</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/atmos13020173" target="_blank" >10.3390/atmos13020173</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Properties of Magnetic Field Fluctuations in Long-Lasting Radial IMF Events from Wind Observation

Popis výsledku v původním jazyce

Long-lasting radial interplanetary magnetic field (IMF) intervals in which IMF points along the solar wind velocity for several hours have many interesting properties. We investigate the average parameters and the behavior of magnetic field fluctuations within 419 such radial intervals. The power spectral density (PSD) calculated over 1-h intervals of a radial IMF is compared with PSDs in adjacent regions prior to and after the radial IMF. We concentrate on (1) the power of IMF fluctuations, (2) the median slopes of PSDs in both inertial and kinetic ranges, (3) the proton temperature and its anisotropy, and (4) the occurrence rate of wavy structures and their polarization. We have shown that the fluctuation amplitude is low in the radial IMF intervals in both magnetohydrodynamic (MHD) and kinetic ranges, and the spectral power increases with the cone angle in the MHD range. We discuss this effect in the light of present knowledge on plasma turbulence and peculiarities of observations of magnetic field variations under the radial background magnetic field. We found that in the radial IMF events, the proton temperature is more isotropic, the occurrence rate of waves is higher, and the waves have no preferred polarization in the frequency range from 0.1 to 1 Hz. It suggests that the radial IMF structure leads to a different development of turbulence than the typical Parker-spiral structure.

Název v anglickém jazyce

Properties of Magnetic Field Fluctuations in Long-Lasting Radial IMF Events from Wind Observation

Popis výsledku anglicky

Long-lasting radial interplanetary magnetic field (IMF) intervals in which IMF points along the solar wind velocity for several hours have many interesting properties. We investigate the average parameters and the behavior of magnetic field fluctuations within 419 such radial intervals. The power spectral density (PSD) calculated over 1-h intervals of a radial IMF is compared with PSDs in adjacent regions prior to and after the radial IMF. We concentrate on (1) the power of IMF fluctuations, (2) the median slopes of PSDs in both inertial and kinetic ranges, (3) the proton temperature and its anisotropy, and (4) the occurrence rate of wavy structures and their polarization. We have shown that the fluctuation amplitude is low in the radial IMF intervals in both magnetohydrodynamic (MHD) and kinetic ranges, and the spectral power increases with the cone angle in the MHD range. We discuss this effect in the light of present knowledge on plasma turbulence and peculiarities of observations of magnetic field variations under the radial background magnetic field. We found that in the radial IMF events, the proton temperature is more isotropic, the occurrence rate of waves is higher, and the waves have no preferred polarization in the frequency range from 0.1 to 1 Hz. It suggests that the radial IMF structure leads to a different development of turbulence than the typical Parker-spiral structure.

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

<a href="/cs/project/GA19-18993S" target="_blank" >GA19-18993S: Přenos energie variací slunečního větru z velkých do malých škál</a><br>

Návaznosti

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

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

Atmosphere

ISSN

2073-4433

e-ISSN

2073-4433

Svazek periodika

13

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

18

Strana od-do

173

Kód UT WoS článku

000778162100001

EID výsledku v databázi Scopus

2-s2.0-85123056691