Sivaraman, K. R; Singh, J; Bagare, S. P; Gupta, S. S
(American Astronomical Society, 1987-02)
The disk-averaged Ca II K profiles obtained at the Kodaikanal solar tower telescope for the period 1969-1984 are used to study the chromospheric variations in the sun as a star. The 1A index shows increases of 18 and 28 ...