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arXiv · 1805.03928

Ca II K spectroheliograms for studies of long-term changes in solar irradiance

Theodosios Chatzistergos·Ilaria Ermolli·Natalie A. Krivova·Sami K. Solanki
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Abstract

We address the importance of historical full disc Ca II K spectroheliograms for solar activity and irradiance reconstruction studies. We review our work on processing such data to enable them to be used in irradiance reconstructions. We also present our preliminary estimates of the plage areas from five of the longest available historical Ca II K archives.

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Theodosios Chatzistergos, Ilaria Ermolli, Natalie A. Krivova, Sami K. Solanki. 2018-05-10. Ca II K spectroheliograms for studies of long-term changes in solar irradiance. https://doi.org/10.1017/s1743921318001825

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