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The quiet-Sun photosphere and chromosphere [PDF]
Philosophical Transactions Series A, Mathematical, Physical, and Engineering Sciences, 2012 Abstract The overall structure and the fine structure of the solar photosphere outside active regions are largely understood, except possibly the important roles of a turbulent near-surface dynamo at its bottom, internal gravity waves at its top and small-scale vorticity. Classical one-dimensional static radiation-escape modelling has
Robert J Rütten
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The role and contribution of magnetic fields, characterized via their magnetic flux, to the statistical structuring of the solar atmosphere [PDF]
Scientific Reports, 2022 The anomalous heating of the solar upper atmosphere is one of the eight key problems in modern astronomy. Moreover, the stratification of the solar atmosphere is an outstanding key-problem in solar physics.
K. J. Li, J. C. Xu, W. Feng
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Frontiers in Astronomy and Space Sciences, 2020 The wealth of observational data available has been instrumental in investigating physical features relevant to solar granulation, supergranulation and Active Regions.
Benoit Tremblay +3 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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Testing the Steady-State Fluctuation Relation in the Solar Photospheric Convection
Entropy, 2020 The turbulent thermal convection on the Sun is an example of an irreversible non-equilibrium phenomenon in a quasi-steady state characterized by a continuous entropy production rate.
Giorgio Viavattene +7 more
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Photospheres of Mira variables [PDF]
International Astronomical Union Colloquium, 1988 Mira variables form an important subgroup of the red giant stars which are typical representatives of stars showing burnt material at their surfaces. Since the photospheres of Miras are not in hydrostatic equilibrium but are characterized by spherically very extended density stratifications, their properties and emitted spectra differ substantially ...
M.S. Bessell +5 more
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Data reduction pipeline for MOF-based synoptic telescopes
Journal of Space Weather and Space Climate, 2020 There are strong scientific cases and practical reasons for building ground-based solar synoptic telescopes. Some issues, like the study of solar dynamics and the forecasting of solar flares, benefit from the 3D reconstruction of the Sun’s atmosphere and
Forte Roberta +17 more
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Photospheric Response to a Flare [PDF]
The Astrophysical Journal, 2018 Abstract Flares produce sudden and permanent changes in the horizontal photospheric magnetic field. In particular, flares generally produce increased magnetic shear in the photospheric field along the neutral line. Recent observations also show that flares can produce sudden photospheric motion.
Michael S. Wheatland +2 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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On the Origin of the Photospheric Magnetic Field
The Astrophysical Journal, 2022 This article presents results that challenge the paradigms that (1) the convection zone is the source of the radial magnetic field in the photosphere and (2) that coronal currents are neutralized from the perspective of the photosphere.
Peter W. Schuck +3 more
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