Switchback-like structures observed by Solar Orbiter

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F21%3A10439900" target="_blank" >RIV/00216208:11320/21:10439900 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=BI7woMUUIo" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=BI7woMUUIo</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202141246" target="_blank" >10.1051/0004-6361/202141246</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Switchback-like structures observed by Solar Orbiter

Popis výsledku v původním jazyce

Context. Rapid polarity reversals of the radial heliospheric magnetic field were discovered by Ulysses and they are now frequently observed as a common near-Sun phenomenon by NASA&apos;s Parker Solar Probe (PSP). Other solar wind missions, including ESA-NASA Solar Orbiter (SolO), also observe similar phenomena. The nature of these fluctuations is unclear, and the relation between the &quot;switchbacks&quot; observed near the Sun and similar events observed at 1 AU is unknown. Aims. We make a detailed case study of the SolO plasma and magnetic field data obtained in a region that is magnetically connected to a coronal hole. We aim to check whether such fluctuations might have the same origin as the &quot;switchbacks&quot; observed by PSP. Methods. We used PSP magnetic field and plasma data to support our analysis of SolO data. We used the magnetic field data, electron pitch angle distributions, proton velocity distribution functions, and alpha-particle parameters measured by SolO to perform a detailed analysis of the observed solar wind perturbations. Results. On 27 September 2020, PSP and SolO were located around the same Carrington longitude and their latitudinal separation was very small. Solar wind plasma and magnetic field data during this time interval confirms that (at least at certain times) the solar wind observed by both spacecraft does originate from the same coronal hole region and that during these time intervals, SolO experiences several short variations similar to the &quot;switchbacks&quot; regularly observed by PSP. Conclusions. The suprathermal electron pitch angle distributions and alpha-particle speed variations indicate that the magnetic field line was bent by 180 degrees by solar wind velocity shear. Variations in electron and proton velocity distribution functions suggest that bent field lines reconnect with each other, producing flux ropes. The observed flux ropes might be the surviving and modified remains of the switchbacks created near Sun and observed by PSP.

Název v anglickém jazyce

Switchback-like structures observed by Solar Orbiter

Popis výsledku anglicky

Context. Rapid polarity reversals of the radial heliospheric magnetic field were discovered by Ulysses and they are now frequently observed as a common near-Sun phenomenon by NASA&apos;s Parker Solar Probe (PSP). Other solar wind missions, including ESA-NASA Solar Orbiter (SolO), also observe similar phenomena. The nature of these fluctuations is unclear, and the relation between the &quot;switchbacks&quot; observed near the Sun and similar events observed at 1 AU is unknown. Aims. We make a detailed case study of the SolO plasma and magnetic field data obtained in a region that is magnetically connected to a coronal hole. We aim to check whether such fluctuations might have the same origin as the &quot;switchbacks&quot; observed by PSP. Methods. We used PSP magnetic field and plasma data to support our analysis of SolO data. We used the magnetic field data, electron pitch angle distributions, proton velocity distribution functions, and alpha-particle parameters measured by SolO to perform a detailed analysis of the observed solar wind perturbations. Results. On 27 September 2020, PSP and SolO were located around the same Carrington longitude and their latitudinal separation was very small. Solar wind plasma and magnetic field data during this time interval confirms that (at least at certain times) the solar wind observed by both spacecraft does originate from the same coronal hole region and that during these time intervals, SolO experiences several short variations similar to the &quot;switchbacks&quot; regularly observed by PSP. Conclusions. The suprathermal electron pitch angle distributions and alpha-particle speed variations indicate that the magnetic field line was bent by 180 degrees by solar wind velocity shear. Variations in electron and proton velocity distribution functions suggest that bent field lines reconnect with each other, producing flux ropes. The observed flux ropes might be the surviving and modified remains of the switchbacks created near Sun and observed by PSP.

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

2021

Kód důvěrnosti údajů

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

Název periodika

Astronomy &amp; Astrophysics

ISSN

0004-6361

e-ISSN

—

Svazek periodika

656

Číslo periodika v rámci svazku

Dec

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

7

Strana od-do

A40

Kód UT WoS článku

000730246400048

EID výsledku v databázi Scopus

2-s2.0-85121663366