Results 11 to 20 of about 9,046 (214)
Photospheric magnetic vortex structures [PDF]
Annales Geophysicae, 2011 Using direct numerical magneto-hydrodynamic (MHD) simulations, we demonstrate the evidence of two physically different types of vortex motions in the solar photosphere.
S. Shelyag +4 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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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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The photosphere of Pleione [PDF]
Symposium - International Astronomical Union, 1994 In this paper we report results concerning the photospheric Balmer discontinuity of Pleione. They show that after the Be → Be-shell phase transitions, the stellar photosphere keeps its characteristics unchanged.
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Vorticity in the solar photosphere [PDF]
, 2010 Aims. We use magnetic and non-magnetic 3D numerical simulations of solar granulation and G-band radiative diagnostics from the resulting models to analyse the generation of small-scale vortex motions in the solar photosphere.Methods.
Shelyag, S. +11 more
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Acoustic wave propagation in the solar sub-photosphere with localised magnetic field concentration: effect of magnetic tension [PDF]
, 2009 Aims: We analyse numerically the propagation and dispersion of acoustic waves in the solar-like sub-photosphere with localised non-uniform magnetic field concentrations, mimicking sunspots with various representative magnetic field configurations ...
Shelyag, S. +14 more
core +1 more source
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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