Solar Activity Indices in the Cycles 21–23
A stable cyclicity of correlation coefficients K corr for some solar activity indices versus F 10.7 was found after monthly averages values analysis. These indices are: Wolf numbers, 10.7 cm radio flux F 10.7, 0.1–0.8 nm background, the total solar irradiance (TSI), Mg II UV-index (280 nm core to wing ratio) and monthly flare count/10. The correlation coefficients of the linear regression of these solar indices versus F 10.7 were analyzed for every year in solar cycles 21, 22 and unusual cycle 23. We found out that the values of yearly determined correlation coefficients K corr for solar activity indices versus F 10.7 show the cyclic variations with stable period closed to half length of 11-year cycle.
KeywordsSolar Activity Solar Cycle Total Solar Irradiance Solar Activity Cycle Wolf Number
The authors thank the RFBR Grant 09-02-01010 and FCPK Grant N 16. 740. 11. 0465 for support of the work.
- 1.Alecseev, I.Yu., Gershberg, R.E. The solar and solar-type stars activity. Astron. Report. 73, 589–597 (1996)Google Scholar
- 2.Baliunas, S.L., Donahue, R.A., Soon, W.H. The topological properties of magnetic helicity. Astrophys. J. 438, 269–280 (1995)Google Scholar
- 3.Bruevich, E.A., Alecseev, I.Yu. Activity of the Sun and solar-type stars. Astrophysics. 50, 187–195 (2007)Google Scholar
- 4.Bruevich, E.A., Nusinov, A.A. Spectrum of short-wave emission for aeronomical calculations for different levels of solar activity. Geomagnetizm i Aeronomiia. 24, 581–585 (1984)Google Scholar
- 5.Lukyanova, R., Mursula, K. Changed relation between sunspot numbers, solar UV/EUV radiation and TSI during the declining phase of solar cycle 23. Journal of Atmospheric and Solar-Terrestrial Physics 73, 235–240 (2011)Google Scholar
- 6.Skupin, J., Weber, M., Bovensmann, H., BurrowsJ.P. The MgII Solar Activity Proxy Indicator Derived From GOME And SCIAMACHY. The 2004 Envisat and ERS Symposium (ESA SP-572), Salzburg, Austria, (2005)Google Scholar
- 7.Vitinsky, Yu.I., Kopecky, M., Kuklin, G.B. The statistics of the spot generating activity of the Sun., Moscow, Nauka (1986)Google Scholar