First detection of acoustic-like flux in the middle solar corona
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F25%3A00639436" target="_blank" >RIV/67985815:_____/25:00639436 - isvavai.cz</a>
Result on the web
<a href="https://hdl.handle.net/11104/0369957" target="_blank" >https://hdl.handle.net/11104/0369957</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1051/0004-6361/202554034" target="_blank" >10.1051/0004-6361/202554034</a>
Alternative languages
Result language
angličtina
Original language name
First detection of acoustic-like flux in the middle solar corona
Original language description
Context. Waves are thought to play a significant role in the heating of the solar atmosphere and the acceleration of the wind. Among the many types of waves observed in the Sun, the so-called p modes with a 3 mHz frequency peak dominate the lower atmosphere. In the presence of magnetic fields, these waves can be converted into magnetohydrodynamic modes, which then leak into the corona through magnetic conduits. High-resolution off-limb observations have revealed signatures of ubiquitous and global 3 mHz oscillations in the corona, although they are limited to low heights and to incompressible modes. Aims. We present high-cadence, high-resolution observations of the corona in the range 1.7-3.6 R-circle dot taken in broad-band 580-640 nm visible light by the Metis coronagraph on board Solar Orbiter. These observations were designed to investigate density fluctuations in the middle corona. Methods. The data were acquired over several days in March 2022, October 2022, and for two days in April 2023. We selected representative regions of the corona on three sample dates. Analysis of the data in those regions revealed the presence of periodic density fluctuations. By examining several time-distance diagrams, we determined the main properties (apparent propagation speed, amplitude) of those fluctuations. We also show power spectra in selected locations in order to determine the dominant frequencies. Results. We found wave-like, compressible fluctuations of low amplitude on the order of 0.1% of the background in several large-scale regions in the corona at least up to 2.5 R-circle dot. We also found that the apparent propagation speeds of these perturbations typically fall in the range 150-450 km s(-1). A power spectrum analysis of the time series revealed an excess power in the range 2-7 mHz, often with peaks at 3 or 5 mHz, i.e. in a range consistent with p-mode frequencies of the lower solar atmosphere.
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
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2025
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
0004-6361
e-ISSN
1432-0746
Volume of the periodical
701
Issue of the periodical within the volume
Sept.
Country of publishing house
FR - FRANCE
Number of pages
17
Pages from-to
A199
UT code for WoS article
001574075800012
EID of the result in the Scopus database
2-s2.0-105016598138