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Heating of the Solar Chromosphere by MHD-Waves
1991We calculate a semi-theoretical model of the lower part of the chromosphere with the aid of the Vernazza et al. (1981) emission coefficients. The equality of the radiative emission coefficient and the absorption coefficient of weak MHD shock waves is assumed.
R. Erdélyi, M. Marik
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Theories of Heating of Solar and Stellar Chromospheres
1981In 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.
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High-frequency acoustic waves are not sufficient to heat the solar chromosphere
Nature, 2005One of the main unanswered questions in solar physics is why the Sun's outer atmosphere is hotter than its surface. Theory predicts abundant production of high-frequency (10-50 mHz) acoustic waves in subsurface layers of the Sun, and such waves are believed by many to constitute the dominant heating mechanism of the chromosphere (the lower part of the ...
Astrid, Fossum, Mats, Carlsson
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Radiation loss and mechanical heating in the low solar chromosphere
Solar Physics, 1976We discuss Ulmschneider's claim to have established that the short-period acoustic wave energy input is the only one able to balance the chromospheric radiation loss. We first review the range of uncertainty in empirical and radiative equilibrium models, on which estimates of the excess radiation coming from mechanical heating rest.
F. Praderie, R. N. Thomas
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Radiation loss and mechanical heating in the solar chromosphere
Solar Physics, 1974The raditation loss of the solar chromosphere is evaluated on the basis of the Harvard Smithsonian Reference Atmosphere. The total radiative flux is found to be between 2.5 and 3.3 E6 erg cm−2 s−1. A discussion of possible heating mechanisms shows that the short period acoustic wave theory is the only one able to balance the chromospheric radiation ...
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