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Molecules in the solar photosphere
Solar Physics, 1969A consideration of the dissociation equilibrium of diatomic molecules in the Utrecht Reference Photosphere leads us to conclude that SH, SiO, CS, HF and HCl may show up in enough concentrations in the solar atmosphere. The number above photosphere for these molecules is comparable with or more than that of MgH.
M C Pande, Pande M C
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On the structure of the solar photosphere
Solar Physics, 1973Based on results from the Soviet Solar Stratospheric Observatory, a model for the photosphere is presented. (WDM)
V A Krat, Krat V A
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Inhomogeneities in the solar photosphere
Solar Physics, 1969A model of the solar photosphere incorporating a simple two-stream representation of granulation is found to give a small but significant improvement in the continuous radiation field over a homogeneous model. It is common to assume that the pressure does not vary with horizontal position; however, this assumption cannot be valid if the material is in ...
Thomas E. Margrave, Thomas L. Swihart
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Waves in the solar photosphere
Solar Physics, 1987Time-sequences of line profile data have been subjected to a unique analysis which produces an amplitude and phase of the velocity and intensity at several line depths for each time sample and spatial point on the Sun. The data have been filtered to pass only the frequencies and spatial wavenumbers of the 5-min band.
Robin Stebbins, PhilipR. Goode
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Magnetic fields in the solar photosphere
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2008Recent high-resolution observations of the surface of the Sun have revealed the fine structure of a vast array of complex photospheric magnetic features. Observations of these magnetic field structures have already greatly enhanced our theoretical understanding of the interactions between magnetic fields and turbulent convection, and future ...
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The composition of the solar photosphere
Advances in Space Research, 2002Abstract The Sun is unique because chemical composition data can be derived from very different layers, from the center to the outermost coronal layers, using very different techniques like helioseismology, spectroscopy, particle collection techniques, … Differences in chemical composition are observed allowing to discover how the different solar ...
N. Grevesse, A.J. Sauval
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Structure of the Solar Photosphere
Space Science Reviews, 1998The majority of measured solar abundances refer to the solar photosphere. In general, when determining photospheric abundances a plane-parallel atmosphere and LTE are assumed. However, the photosphere is structured by granulation, magnetic fields and p-modes. They change line profiles by the thermal inhomogeneities and wavelength shifts they introduce.
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1965
The sun has a radius R = 7 × 105 km, and is situated about rE = 1.5 × 108 km from the earth. Since the mass of the sun is M= 2 × 1033 g the average density can be determined as 1.4 gcm-3. However, the density changes from 70 gem-3 at the solar centre, where the temperature is 14 × 106 °K, to 10-7 gem-3 in the photosphere.
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The sun has a radius R = 7 × 105 km, and is situated about rE = 1.5 × 108 km from the earth. Since the mass of the sun is M= 2 × 1033 g the average density can be determined as 1.4 gcm-3. However, the density changes from 70 gem-3 at the solar centre, where the temperature is 14 × 106 °K, to 10-7 gem-3 in the photosphere.
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On the microturbulence in the solar photosphere
Solar Physics, 1979The velocity of microturbulent motions in the solar photosphere at the level of formation of weak Fraunhofer lines (h ∼ 150 km) is found to be 0.1 ± 0.2 km s−1. The observations have been performed with the double-pass spectrometer in Kiev. Apart from thermal motions and damping effects we have taken into account convective and wave motions when ...
R. I. Kostik, T. V. Orlova
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The solar photospheric abundance of iron
Solar Physics, 1975A new value of the solar photospheric abundance of iron, independent of line-shape parameters, is derived.
E. Bi�mont, N. Grevesse
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