Results 171 to 180 of about 173,010 (211)

Stellar Chromospheres, Coronae, and Winds

1992
Chromospheres, 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 ...
R. Pallavicini
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Solar and stellar chromospheres

2005
This 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.
R. Hammer
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Energy Balance in Solar and Stellar Chromospheres

1981
The spectrum from a specific region of the sun or from a star can be used to determine the temperature-density stratification and other physical properties of the emitting atmospheric layers. We need such a description of the atmosphere in order to understand the causes of solar activity and the nature of various stellar phenomena.
E. Avrett
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Stellar Chromospheres

Science, 1966
J. Linsky
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Theories of Heating of Solar and Stellar Chromospheres

1981
In the outer atmosphere of stars a rise of the kinetic temperature to values above Teff is possible only if a large and persistent amount of mechanical heating is present. Constraints derived from empirical chromosphere models allow selection of important heating mechanisms from among a great number of possible processes.
P. Ulmschneider
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Stellar chromospheres

Space Science Reviews, 1979
P. Ulmschneider
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Stellar and Solar Chromospheres and Attendant Phenomena

The Sun as a Guide to Stellar Physics, 2019
T. Ayres
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Solar and stellar chromospheric contrast

Solar Physics, 1994
We 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, Sergio R. Restaino, Stephen L. Keil   +2 more
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Stellar chromospheric temperatures

Astrophysics and Space Science, 1983
The 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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Partially coherent scattering in stellar chromospheres. II - The first-order escape probability method. III - A second-order probability method

, 1992
K. G. Gayley
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