Results 21 to 30 of about 3,957 (226)
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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Investigating the Origin of the First Ionization Potential Effect With a Shell Turbulence Model
Frontiers in Astronomy and Space Sciences, 2021 The enrichment of coronal loops and the slow solar wind with elements that have low First Ionization Potential, known as the FIP effect, has often been interpreted as the tracer of a common origin.
Victor Réville +6 more
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International Astronomical Union Colloquium, 1980 Important progress in our understanding of stellar chromospheres has occurred in the past few years as a result of new observations, developments in spectral line formation theory, and the application of that theory to the construction of detailed model chromospheres.
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Chromospheric Seismology [PDF]
Symposium - International Astronomical Union, 1988 The aim of the present study is to examine whether seismologic diagnostic techniques may be used to improve the models of the solar chromosphere. We are mainly concerned by oscillations observed in the cores of strong lines such as the resonance lines of Ca II or Mg II. It is intuitive, and confirmed by numerical simulations (Gouttebroze and Leibacher,
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Earth and Space Science, 2020 Solar prominences are structures of importance because of their role in polar field reversal. We study the long‐term variation of the time latitude distribution of solar prominences in this article.
Subhamoy Chatterjee +4 more
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Solar-Terrestrial Physics, 2020 We have studied two regions located at the base of a coronal hole. For the K₁ intensity minima and K₂ peaks, which form between the upper photosphere and the lower chromosphere and in the lower chromosphere respectively, a number of Ca II line parameters
I.P. Turova +2 more
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Open Astronomy, 2021 We present intensity curves of solar flares obtained in the Hα hydrogen line and CaII H, CaIR 8542Å lines using multichannel spectrographs of Ondřejov Observatory (Czech Republic) for the period 2000–2012.
Kupryakov Yurij Alekseevich +5 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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Wave Heating of the Solar Chromosphere
, 2022 The solar chromosphere is well known to be in a radiative balance that requires an unac- counted source of heating. In this thesis I present observational constraints on the wave energy flux in the solar chromosphere, which is one of the favored ...
Molnar, Momchil Emil
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