Results 11 to 20 of about 14,964 (204)
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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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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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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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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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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