Results 1 to 10 of about 1,010,043 (218)
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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Rotational Characteristics of the Solar Transition Region Using SDO/AIA 304 Å Images
The Astrophysical Journal, 2023 To date, the rotational characteristics of the solar transition region remain unclear. In this work, by applying the flux modulation method to the images derived from the Solar Dynamics Observatory/Atmospheric Imaging Assembly between 2011 and 2022 at ...
Qian-Rui Wu +6 more
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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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Propagating and Stationary Bright Knots in the Quiet Sun
The Astrophysical Journal Letters, 2022 The question of what heats the solar chromosphere and corona remains one of the most important puzzles in solar physics and astrophysics. Up to now, two mechanisms are considered to work in heating the chromosphere and corona: magnetic reconnection and ...
Jun Zhang +9 more
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The Astrophysical Journal Letters, 2023 The heating of the chromosphere in internetwork regions remains one of the foremost open questions in solar physics. In the present study, we tackle this old problem by using a very-high-spatial-resolution simulation of quiet-Sun conditions performed ...
Juan Martínez-Sykora +5 more
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Element Abundances in Impulsive Solar Energetic Particle Events
The Astrophysical Journal, 2023 We outline and discuss a model for the enhanced abundances of trans-Fe elements in impulsive solar energetic particle (SEP) events, where large mass-dependent abundance enhancements are frequently seen.
J. Martin Laming, Natsuha Kuroda
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The Magnetic Sensitivity of the (250–278 nm) Fe ii Polarization Spectrum
The Astrophysical Journal, 2023 This paper presents a theoretical investigation of the polarization and magnetic sensitivity of the near-ultraviolet (near-UV) solar spectral lines of Fe ii between 250 and 278 nm.
David Afonso Delgado +2 more
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The Astrophysical Journal, 2023 The ponderomotive force has been suggested to be the main mechanism to produce the so-called first ionization potential (FIP) effect—the enrichment of low-FIP elements observed in the outer solar atmosphere, in the solar wind, and in solar energetic ...
Juan Martínez-Sykora +5 more
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The Astrophysical JournalWe report the first detection of a magnetic discontinuity in the upper solar chromosphere associated with a coronal loop brightening. Our findings are based on novel observations obtained by the Chromospheric LAyer SpectroPolarimeter (CLASP2.1 ...
Donguk Song +17 more
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How Are the Abnormally Hot Chromosphere and Corona Heated by the Solar Magnetic Fields?
The Astrophysical JournalThe corona is a structure possessed by stars, including the Sun. The abnormal heating of the solar corona and chromosphere is one of the greatest mysteries in modern astronomy.
K. J. Li +5 more
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