Results 21 to 30 of about 8,745 (214)
Symposium - International Astronomical Union, 1987 The temperature stratifications and the emitted fluxes of Mira model photospheres based upon the extended density distribution of a pulsation model differ substantially from those of conventional model photospheres based upon a hydrostatic density distribution.
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Equation of state for solar near-surface convection [PDF]
Annales Geophysicae, 2015 Numerical 3-D radiative hydrodynamical simulations are the main tool for the analysis of the interface between the solar convection zone and the photosphere. The equation of state is one of the necessary ingredients of these simulations.
N. Vitas +4 more
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Diminishing activity of recent solar cycles (22–24) and their impact on geospace
Journal of Space Weather and Space Climate, 2019 This study examines the variation of different energies linked with the Sun and the Earth’s magnetosphere-ionosphere systems for solar cycles (SCs) 22–24 for which the gradual decrease in the solar activity is noticed.
Kakad Bharati +3 more
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Global solar photospheric and coronal magnetic field over activity cycles 21–25
Journal of Space Weather and Space ClimateThe evolution of the global solar magnetic field from the beginning of cycle 21 (mid-1970s) until the currently-ascending cycle 25 is described using photospheric full-disk and synoptic magnetograms from NSO Kitt Peak Vacuum Telescope (KPVT) 512-channel ...
Petrie Gordon J. D.
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The Astrophysical Journal, 2023 In solving the solar coronal heating problem, it is crucial to comprehend the mechanisms by which energy is conveyed from the photosphere to the corona. Recently, magnetic tornadoes, characterized as coherent, rotating magnetic-field structures extending
Hidetaka Kuniyoshi +3 more
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Photospheric magnetoconvection [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractMagnetic fields, convective motions and radiative energy transport all strongly influence each other in the solar photosphere. Attempts to understand, at a quantitative level, the diverse phenomona seen in the photosphere have relied on increasingly powerful computers since the 1980's.
Cameron, R., Schüssler, M., Vögler, A.
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Probing oscillations in the lower solar atmosphere with the FRANCIS integral field unit
Frontiers in Astronomy and Space SciencesThe photosphere is dominated by 3 mHz oscillations, and as we move upward through the solar atmosphere, the dominant frequency is progressively filtered up to 5 mHz, which is commonly observed ubiquitously in the chromosphere. However, the interaction of
S. D. T. Grant +9 more
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Adapted Empirical Modeling of Near‐Sun Solar‐Wind Speeds for Use in Ensemble Forecasts
Space Weather, Volume 24, Issue 9, September 2026.Abstract Solar wind science and forecasting relies on empirical relations between modeled coronal magnetic‐field structure—particularly flux‐tube expansion and distance to coronal hole boundary—and solar‐wind speed. There is lots of uncertainty in these relations, creating large uncertainties in the inner‐boundary conditions to heliospheric models ...
N. O. Edward‐Inatimi +7 more
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The ORCA‐TWIN qCMOS Experiment I. Science Case and Commissioning at Calar Alto Observatory
Astronomische Nachrichten, Volume 347, Issue 7, August 2026.ABSTRACT We describe a pilot study to explore a new generation of fast and low noise CMOS image sensors for time domain astronomy, using two remote telescopes with a baseline of 1635 km. The experiment involves direct imaging with novel qCMOS image sensor technology that combines fast readout with sub‐electron readout noise.
Martin M. Roth +20 more
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Forecasting Continuum Intensity for Solar Active Region Emergence Prediction Using Transformers
Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 4, August 2026.Abstract Early and accurate prediction of solar active region (AR) emergence is crucial for space weather forecasting. Building on established Long Short‐Term Memory (LSTM) based approaches for forecasting the continuum intensity decrease associated with AR emergence, this work expands the modeling with new architectures and targets.
Jonas Tirona +7 more
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