Results 21 to 30 of about 5,203 (216)
Dissipation of Magnetohydrodynamic Waves in the Solar Stratified Flux Tubes [PDF]
Iranian Journal of Astronomy and Astrophysics, 2023 Chromosphere is the second layer of the Sun with high variability. The increase of the temperature and the decrease of the density are observed in this layer. This unusual behavior is one of the most important problems in the solar corona.
Zahra Fazel
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The quiet sun at mm wavelengths as seen by ALMA
Frontiers in Astronomy and Space Sciences, 2022 Solar observations at sub-mm, mm and cm wavelengths offer a straightforward diagnostic of physical conditions in the solar atmosphere because they yield measurement of brightness temperature which, for optically thick features, equals intrinsic ...
Costas E. Alissandrakis +2 more
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Moreton waves and EUV waves in the solar atmosphere
地球与行星物理论评, 2023 Solar eruptions, which generate various types of wave phenomena in the solar atmosphere, are sources of space weather perturbations. These waves not only transport a large amount of energy, but also illuminate the properties of the magnetic field and ...
Pengfei Chen
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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
openaire +2 more sources
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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Structure of the Solar Atmosphere: A Radio Perspective
Frontiers in Astronomy and Space Sciences, 2020 Solar radio emission has been providing information about the Sun for over half a century. In order to fully exploit this information, one needs to have a broader view of the solar atmosphere, which cannot be provided by radio observations alone.
Costas E. Alissandrakis
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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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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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