The Solar Minimum Eclipse of 2019 July 2. II. The First Absolute Brightness Measurements and MHD Model Predictions of Fe x, xi, and xiv out to 3.4 R (circle dot)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F22%3APU146268" target="_blank" >RIV/00216305:26210/22:PU146268 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.3847/1538-4357/ac8101/pdf" target="_blank" >https://iopscience.iop.org/article/10.3847/1538-4357/ac8101/pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-4357/ac8101" target="_blank" >10.3847/1538-4357/ac8101</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The Solar Minimum Eclipse of 2019 July 2. II. The First Absolute Brightness Measurements and MHD Model Predictions of Fe x, xi, and xiv out to 3.4 R (circle dot)

Popis výsledku v původním jazyce

We present the spatially resolved absolute brightness of the Fe x, Fe xi, and Fe xiv visible coronal emission lines from 1.08 to 3.4 R (circle dot), observed during the 2019 July 2 total solar eclipse (TSE). The morphology of the corona was typical of solar minimum, with a dipole field dominance showcased by large polar coronal holes and a broad equatorial streamer belt. The Fe xi line is found to be the brightest, followed by Fe x and Fe xiv (in disk B (circle dot) units). All lines had brightness variations between streamers and coronal holes, where Fe xiv exhibited the largest variation. However, Fe x remained surprisingly uniform with latitude. The Fe line brightnesses are used to infer the relative ionic abundances and line-of-sight-averaged electron temperature (T ( e )) throughout the corona, yielding values from 1.25 to 1.4 MK in coronal holes and up to 1.65 MK in the core of streamers. The line brightnesses and inferred T ( e ) values are then quantitatively compared to the Predictive Science Inc. magnetohydrodynamic model prediction for this TSE. The MHD model predicted the Fe lines rather well in general, while the forward-modeled line ratios slightly underestimated the observationally inferred T ( e ) within 5%-10% averaged over the entire corona. Larger discrepancies in the polar coronal holes may point to insufficient heating and/or other limitations in the approach. These comparisons highlight the importance of TSE observations for constraining models of the corona and solar wind formation.

Název v anglickém jazyce

The Solar Minimum Eclipse of 2019 July 2. II. The First Absolute Brightness Measurements and MHD Model Predictions of Fe x, xi, and xiv out to 3.4 R (circle dot)

Popis výsledku anglicky

We present the spatially resolved absolute brightness of the Fe x, Fe xi, and Fe xiv visible coronal emission lines from 1.08 to 3.4 R (circle dot), observed during the 2019 July 2 total solar eclipse (TSE). The morphology of the corona was typical of solar minimum, with a dipole field dominance showcased by large polar coronal holes and a broad equatorial streamer belt. The Fe xi line is found to be the brightest, followed by Fe x and Fe xiv (in disk B (circle dot) units). All lines had brightness variations between streamers and coronal holes, where Fe xiv exhibited the largest variation. However, Fe x remained surprisingly uniform with latitude. The Fe line brightnesses are used to infer the relative ionic abundances and line-of-sight-averaged electron temperature (T ( e )) throughout the corona, yielding values from 1.25 to 1.4 MK in coronal holes and up to 1.65 MK in the core of streamers. The line brightnesses and inferred T ( e ) values are then quantitatively compared to the Predictive Science Inc. magnetohydrodynamic model prediction for this TSE. The MHD model predicted the Fe lines rather well in general, while the forward-modeled line ratios slightly underestimated the observationally inferred T ( e ) within 5%-10% averaged over the entire corona. Larger discrepancies in the polar coronal holes may point to insufficient heating and/or other limitations in the approach. These comparisons highlight the importance of TSE observations for constraining models of the corona and solar wind formation.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2022

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

935

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

13

Strana od-do

„173“-„“

Kód UT WoS článku

000843863000001

EID výsledku v databázi Scopus

2-s2.0-85137055096