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PREDICTED ULTRAVIOLET SPECTRA FROM STELLAR CHROMOSPHERES
Journal of Quantitative Spectroscopy and Radiative Transfer, 1968Abstract Perhaps the most tangible evidence of the existence and structure of postulated stellar chromospheres of otherwise relatively cool stars would be the detection of an intense ultraviolet spectrum. The solar case for which a variety of measurements is available now reveals that the observed spectrum depends in a very complex and not thoroughly
L. Oster, N.P. Patterson
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Solar and stellar chromospheric contrast
Solar Physics, 1994We present an analysis of disk-integrated spectra of the Caii K line (3933.68 A). The selection of parameters in the line profile, and the correlations between them, follow the work of Smith (1960), but represent an innovative aspect in the fact that our data are spatially integrated.
Robert A. Donahue +2 more
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Stellar chromospheric temperatures
Astrophysics and Space Science, 1983The emission doublet 2800 Mgii of stellar chromospheric origin is always stronger than the emission in the Lα line of hydrogen. At the same time, the ratio of their fluxes,Q=F(Mgii)/F(Lα), varies over a wide range— from 2 up to 20 in stars of one and the same type.
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Stellar Chromospheres, Coronae, and Winds
1986The three subjects listed in the title of this chapter were originally defined for phenomena that are observed in the Sun. Observations of other stars have now been made at a wide range of wavelengths and have revealed that one or more of these phenomena are present in stars of every class.
J. P. Cassinelli, K. B. MacGregor
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Stellar Chromospheres, Coronae, and Winds (Invited Review)
Astrophysics and Space Science, 1986Within the last few years there have been important advances in our understanding of the chromospheres, coronae, and winds of late-type stars. This progress has been the result of ultraviolet and X-ray observations obtained from space with the International Ultraviolet Explorer andEinstein satellites. In addition, ground-based astronomy has contributed
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Solar and stellar chromospheres
2005This review attempts to highlight two fundamental and complementary aspects of the chromospheric phenomenon; viz., global properties of stellar chromospheres and their variation among the stars, and the underlying fine structure that affects or determines these global properties.
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Stellar Chromospheres, Coronae, and Winds
1992Chromospheres, coronae, and winds similar to those observed on the Sun have been detected in a variety of cool stars. In many cases, especially for main-sequence stars, there is good evidence that the processes leading to non-radiative plasma heating and wind acceleration are the same as for the Sun, although the radiative losses from stellar ...
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Science (New York, N.Y.), 2010
Besides being of intrinsic interest, these outer stellar envelopes provide very useful astrophysical tools. ; © 1966 American Association for the Advancement of Science.
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Besides being of intrinsic interest, these outer stellar envelopes provide very useful astrophysical tools. ; © 1966 American Association for the Advancement of Science.
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Chromospheric Lines as Diagnostics of Stellar Oscillations
2008Gravitational waves in the chromosphere, theorized as early as 1963 [10], are thoroughly explored in the more recent papers by [7, 8]. Theory predicts that the convective overshoot in the upper photosphere and low chromosphere will readily excite gravity waves.
Diane B. Paulson +6 more
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Stellar Chromospheres: The Source of UV Emission
2019The lower layer of a star’s atmosphere, its photosphere, has a thermal structure that decreases outward controlled by the balance of radiative and convection heat from below and the loss of radiation to space. With increasing height in a stellar atmosphere, magnetic heating processes become important in the energy balance, forcing the temperature to ...
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