Periodicities in the green corona for the sun as a star

✍ Scribed by Vojtech Rušin; Juraj Zverko

• Publisher: Springer
• Year: 1990
• Tongue: English
• Weight: 336 KB
• Volume: 128
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00154162

✦ Synopsis

A coronal index (CI) derived from the limb observations of the 530.3 nm emission corona (green corona) over 1964-1987 was analyzed by the Fourier transform technique (FTT) to find periodicity in this layer of solar atmosphere. As expected, two pronounced periods were indicated: the rotational, about 27 d, and the activity cycle length, 11 years. Beside these there are seen other periodicities of less significancies, namely of about 5, 2.2, 1 and 0.5 year. The values of these periodicities in individual cycles 20 and 21 slightly differs that could be related to different activity zone depths beneath the photosphere.