Solar-cycle dependence of galactic cosmic ray flux

✍ Scribed by G. D. Parker

• Publisher: Springer
• Year: 1973
• Tongue: English
• Weight: 979 KB
• Volume: 31
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00156088

✦ Synopsis

The coronal green line intensity is inappropriate for correlation studies of galactic cosmic ray variations. Being a non-monotonic function of coronal temperature, the green line intensity is a good index of neither coronal temperature nor solar wind speed. A more appropriate measure of coronal activity is the intensity of the electron corona. Two-dimensional observations of the K-corona trace changes in coronal morphology during the solar cycle. An index based on four years of K-coronal measurements made in Hawaii shows that activity in the lower corona is not better correlated than sunspot number with long-term modulation. Correlation analysis defines the time lag of modulation much too poorly to permit its use in estimating the size of the heliosphere.