High-resolution spectroscopy of a surge in an emerging flux region
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F20%3A00537138" target="_blank" >RIV/67985815:_____/20:00537138 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.1051/0004-6361/201936762" target="_blank" >https://doi.org/10.1051/0004-6361/201936762</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1051/0004-6361/201936762" target="_blank" >10.1051/0004-6361/201936762</a>
Alternative languages
Result language
angličtina
Original language name
High-resolution spectroscopy of a surge in an emerging flux region
Original language description
The active region started as a bipolar region with continuous flux emergence when a new flux system emerged in the leading part during the VTT observations, resulting in two homologous surges. While flux cancellation at the base of the surges provided the energy for ejecting the cool plasma, strong proper motions of the leading pores changed the magnetic field topology making the region susceptible to surging. Despite the surge activity in the leading part, an arch filament system in the trailing part of the old flux remained stable. Thus, stable and violently expelled mass-loaded ascending magnetic structures can coexist in close proximity. Investigating the height dependence of LOS velocities revealed the existence of neighboring strong up- and downflows. However, downflows occur with a time lag. The opacity of the ejected cool plasma decreases with distance from the base of the surge, while the speed of the ejecta increases. The location at which the surge becomes invisible in H alpha corresponds to the interface where the surge brightens in HeII lambda 304 angstrom. Broad-shouldered and dual-lobed H alpha profiles suggests accelerated or decelerated and highly structured LOS plasma flows. Significantly broadened H alpha profiles imply significant heating at the base of the surges, which is also supported by bright kernels in UV and EUV images uncovered by swaying motions of dark fibrils at the base of the surges.Conclusions. The interaction of newly emerging flux with pre-existing flux concentrations of a young, diffuse active region provided suitable conditions for two homologous surges. High-resolution spectroscopy revealed broadened and dual-lobed H alpha profiles tracing accelerated or decelerated flows of cool plasma along the multi-threaded structure of the surge.
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
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OECD FORD branch
10308 - Astronomy (including astrophysics,space science)
Result continuities
Project
<a href="/en/project/GC18-08097J" target="_blank" >GC18-08097J: Quiet-Sun Magnetic Fields and Newly Emerging Flux – Dynamics, Energetics, and Upper Atmospheric Response</a><br>
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2020
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Astronomy & Astrophysics
ISSN
1432-0746
e-ISSN
—
Volume of the periodical
639
Issue of the periodical within the volume
July
Country of publishing house
FR - FRANCE
Number of pages
12
Pages from-to
A19
UT code for WoS article
000549972400008
EID of the result in the Scopus database
2-s2.0-85087898280