Cycles of the magnetic activity of the Sun and solar-type stars and simulation of their fluxes

Abstract

The application of the Wavelet analysis and Fourier analysis to the dataset of variations of radiation fluxes of solar-like stars and the Sun is examined. In case of the Sun the wavelet-analysis helped us to see a set of values of periods of cycles besides "11-year" cycle: the long-duration cycles of 22-year, 40-50 year and 100-120 year and short-duration cycles of 2-3,5 years and 1,3-year. We present a method of the chromospheric flux simulation using the 13 late-type stars, which have well-determined cyclic flux variations similar to the 11-year solar activity cycle. Our flux prediction is based on the chromospheric calcium emission time series measurements from the Mount Wilson Observatory and comparable solar dataset. We show that solar three -component modeling well explains the stellar chromospheric observations.

On the global magnetic activity and dynamo of the Sun and solar-type stars

“…So the above regression equation ( 1) agrees well within the errors with the theoretical formula (10).…”

“…At present the observations of active atmospheres of solar-type stars are regularly held in the framework of the "HK-project" at Mount Wilson observatory (Baliunas et al 1995;Radick et al 1998;Lockwood et al 2007) In the work (Bruevich & Rozgacheva 2012) we published the results of processing of the observations of cyclic variations of chromospheric radiation of the 52 solar-type stars and the Sun in the form of a Table . In this Table an information about the periods of rotation and effective temperatures of stars, about the duration of their "11-year" and quasibiennial cycles is contained. The periods of cycles of activity are given according to the calculations of the authors of this work together with the definition of "11-year" periods with help the authors of "HK-project" (Baliunas et al 1995).…”

“…We used the data of observations of variations of chromospheric radiation of the Sun and of 52 solar-type "HK-project" stars from the Table, published in (Bruevich & Rozgacheva 2012) for statistical analysis and the search if there is a possible linear relationship between the periods of rotation Prot of the stars and their effective temperature T ef f . Diagram "the rotation period -the effective temperature" for 52 solar-type stars is shown in Fig.…”

“…The diagram of "the duration of the cycle -the effective temperature" (T 11 is the period of " 11-year" cycles) for 46 stars from Table, published in (Bruevich & Rozgacheva 2012) is shown in Fig. 2.…”

“…Consider, first, that the angular velocity of rotation of the star connected with star's effective temperature as ratio Ω ∼ T ef f 4 , which follows from the formula (10).…”