Ca II H+K fluxes from S-indices of large samples: a reliable and consistent conversion based on PHOENIX model atmospheres

M. Mittag, J. H. M. M. Schmitt, K.‐P. Schröder

Astronomy and Astrophysics · 2012 · 100 citations · 19 references

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Concepts

Abstract

Context. Historic stellar activity data based on chromospheric line emission using O.C. Wilson’s S-index reach back to the 1960ies and represent a very valuable data resource both in terms of quantity and time-coverage. However, these data are not flux-calibrated and are therefore difficult to compare with modern spectroscopy and to relate to quantitative physics.

References

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