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Alfvén Wave Connection between the Chromosphere and the Corona of the Sun: An Analytical Study
The Astrophysical Journal, 2023 Alfvén waves are closely relevant to the three outstanding problems in the solar corona: coronal heating, solar wind acceleration, and the fractionization of low first ionization potential (FIP) elements.
Jongchul Chae, Kyoung-Sun Lee
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Review and comparison of MHD wave characteristics at the Sun and in Earth’s magnetosphere
Solar-Terrestrial Physics, 2022 Magnetohydrodynamic (MHD) waves play a crucial role in the plasma processes of stellar atmospheres and planetary magnetospheres. Wave phenomena in both media are known to have similarities and unique traits typical of each system.
Chelpanov M. A. +6 more
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A CHROMOSPHERIC CONUNDRUM? [PDF]
The Astrophysical Journal, 2010 We examine spectra of the Ca II H line, obtained under good seeing conditions with the VTT Echelle Spectrograph in June of 2007, and higher resolution data of the Ca II 8542 Angstrom line from Fabry-Perot instruments. The VTT targets were areas near disk center which included quiet Sun and some dispersed plage.
Judge, Philip +3 more
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CAII lines in a quiet region on the Sun I. Dynamic processes in the solar atmosphere
Solar-Terrestrial Physics, 2023 We have studied oscillation processes in the quiet Sun outside a coronal hole at different levels of the solar chromosphere. The study was based on spectroscopic observations of ionized calcium lines (K, H, and 849.8 nm) obtained by the Sayan Solar ...
Turova I. P. +2 more
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Review of Fast Solar Jets and Coronal Mass Ejections [PDF]
Iranian Journal of Astronomy and Astrophysics, 2023 The Sun is a magnetically active star. It has a powerful magnetic field that shifts slightly from year to year until it reverses about every eleven years. The sun's magnetic field has many effects, the collection of which is called solar activity such as,
Sima Zeighami, Ehsan Tavabi
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Superpenumbral chromospheric flare [PDF]
Research in Astronomy and Astrophysics, 2018 13 pages, 8 figures, 1 ...
Liu, S. +4 more
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Inferring depth-dependent plasma motions from surface observations using the DeepVel neural network
Journal of Space Weather and Space Climate, 2021 Coverage of plasma motions is limited to the line-of-sight component at the Sun’s surface. Multiple tracking and inversion methods were developed to infer the transverse motions from observational data.
Tremblay Benoit +4 more
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Subarcsecond Imaging of a Solar Active Region Filament With ALMA and IRIS
Frontiers in Astronomy and Space Sciences, 2022 Quiescent filaments appear as absorption features on the solar disk when observed in chromospheric lines and at continuum wavelengths in the millimeter (mm) range. Active region (AR) filaments are their small-scale, low-altitude analogues, but they could
J. M. da Silva Santos +6 more
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An ALMA Observation of Time Variations in Chromospheric Temperature of a Solar Plage Region
Frontiers in Astronomy and Space Sciences, 2022 Nanoflares and the shock formation of magnetohydrodynamic waves in the solar chromosphere have been considered as key physical mechanisms of the heating of the chromosphere and corona.
Masashi Abe +5 more
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Incoherent Solar Radio Emission
Frontiers in Astronomy and Space Sciences, 2020 Incoherent solar radio radiation comes from the free-free, gyroresonance, and gyrosynchrotron emission mechanisms. Free-free is primarily produced from Coulomb collisions between thermal electrons and ions.
Alexander Nindos
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