Results 21 to 30 of about 958,871 (209)
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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Ionisation in the Solar Chromosphere [PDF]
Nature, 1920 IT is well known that the spectrum of the upper layers of the solar chromosphere is chiefly composed of those lines which are relatively more strengthened in the spark than in the arc, and which Sir Norman Lockyer originally styled enhanced lines. The best-known examples are the calcium H and K and the strontium pair (4216, 4077).
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Solar Spectroscopy and (Pseudo-)Diagnostics of the Solar Chromosphere [PDF]
, 2010 I first review trends in current solar spectrometry and then concentrate on comparing various spectroscopic diagnostics of the solar chromosphere. Some are actually not at all chromospheric but just photospheric or clapotispheric and do not convey ...
Raveendran, A.S.N. +6 more
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MHD turbulence and heating of the open field-line solar corona [PDF]
, 2003 This paper discusses the possibility that heating of the solar corona in open field-line regions emanating from coronal holes is due to a nonlinear cascade, driven by low-frequency or quasi-static magnetohydrodynamic fluctuations.
Dmitruk, Pablo +13 more
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Investigating Alfvénic wave propagation in coronal open-field regions [PDF]
, 2015 The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén waves.
Morton, Richard +2 more
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Solar flux emergence : a three-dimensional numerical study [PDF]
, 2008 Flux is continually emerging on the Sun, making its way from the solar interior up into the atmosphere. Emergence occurs on small-scales in the quiet Sun where magnetic fragments emerge, interact and cancel and on large-scales in active regions where ...
Murray, Michelle J.
core +2 more sources
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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Magnetoacoustic Heating of the Solar Chromosphere
The Astrophysical Journal, 1991 Long-period acoustic waves generated in the solar convection zone can propagate radially outward through the overlying atmosphere and get resonantly absorbed in the magnetic arches of the low-lying chromospheric canopy. The resulting Poynting and acoustic flux that enters the magnetic canopy in the network regions is demonstrated to be adequate to ...
Joseph M. Davila, S. M. Chitre
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Magnetohydrodynamic waves in structured atmospheres [PDF]
, 2012 The effect of structuring, in the form of magnetic or density inhomogeneities, on the magnetohydrodynamic (mhd) waves of an infinite plasma is investigated.
Edwin, Patricia Mary
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Resonance Lines in the Solar Chromosphere [PDF]
Symposium - International Astronomical Union, 1970 Stigmatic balloon spectra of the Sun in the vicinity of 2800 Å were obtained on September 22, 1968 and April 30, 1969. We compare the observed profiles of the H and K lines of ionized magnesium with the computed profiles of Athay and Skumanich and of Dumont. The discrepancy between observed and computed profiles of the Mgii lines is considerable. It is
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