Variations of solar activity over the last 100 years using observations in CaII-K spectral line.
Abstract
We present analysis of synoptic full disk daily spectroheliograms taken in CaII-K spectral line at Kodaikanal Observatory (1907-1999), Mount Wilson Observatory (1915-1985), and the National Solar Observatory at Sacramento Peak (1963-2002). All Photographic images were digitized and reduced in a systematic way. The data reduction included circularization of solar disk images and correction for scattered light and response function of photographic film. Using localized intensity threshold, we identified three types of chromospheric features: plage, network element, and ephemeral bright point; and we study coordinates, total area, and irradiance of these features. In this talk, we discuss relationship between sunspot activity, total area of chromospheric plages and their irradiance over a period of several solar cycles.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2008
- Bibcode:
- 2008AGUSMSP53B..02T
- Keywords:
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- 7599 General or miscellaneous