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Irradiance Models Based on Solar Magnetic Fields

Published online by Cambridge University Press:  12 April 2016

Karen L. Harvey
Karen L. Harvey*
Affiliation:
Solar Physics Research Corporation, Tucson, AZ 85718, USA

Abstract

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A method to separate the active region and quiet network components of the magnetic fields in the photosphere is described and compared with the corresponding measurements of the He I λ 10830 absorption. The relation between the total He I absorption and total magnetic flux in active regions is roughly linear and differs between cycles 21 and 22. There appears to no relation between these two quantities in areas outside of active regions. The total He I absorption in the quiet Sun (comprised of network, filaments, and coronal holes) exceeds that in active regions at all times during the cycle. As a whole, active regions of cycle 22 appear to be less complex than the active regions of cycle 21, hinting at one possible cause for a differing relation between spectral-irradiance variations and the underlying magnetic flux for these two cycles.

Type
Empirical Models of Solar Total and Spectral Irradiance Variability
Information
International Astronomical Union Colloquium , Volume 143: The Sun as a Variable Star: Solar and Stellar Irradiance Variations , 1994 , pp. 217 - 225
Copyright
Copyright © Kluwer 1994

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