Solar Physics

, 294:165 | Cite as

Non-Equilibrium Spectrum Formation Affecting Solar Irradiance

  • Robert J. RuttenEmail author
Editor’s Choice
Part of the following topical collections:
  1. Irradiance Variations of the Sun and Sun-like Stars


This is an overview of non-equilibrium aspects of the formation of solar continua and lines affecting the contributions by magnetic network and plage to spectrally resolved solar irradiance. After a brief summary of these contributions and a compact refresher of solar spectrum formation, the emphasis is on graphical exposition. Major obstacles for simulation-based irradiance studies are how to cope with NLTE scattering in the violet and ultraviolet line haze and how to cope with retarded hydrogen opacities in infrared and mm radiation.


Spectrum Solar irradiance 



I thank the organizers of Focus Meeting FM9 at the 30th General Assembly of the IAU for inviting me to review this topic and so triggering this publication. I thank the reviewer for suggesting many improvements and ADS for assistance with its page serving.

Disclosure of Potential Conflicts of Interest

The author declares to have no conflicts of interest.


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© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Lingezicht AstrophysicsDeilThe Netherlands
  2. 2.Institute of Theoretical AstrophysicsUniversity of OsloOsloNorway
  3. 3.Rosseland Centre for Solar PhysicsUniversity of OsloOsloNorway

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