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Modulated stellar and solar cycles: parallels and differences

Published online by Cambridge University Press:  05 July 2012

K. Oláh ,
L. van Driel-Gesztelyi  and
K. G. Strassmeier
K. Oláh
Affiliation:
Konkoly Observatory, Budapest, Hungary email: olah@konkoly.hu
L. van Driel-Gesztelyi
Affiliation:
Konkoly Observatory, Budapest, Hungary email: olah@konkoly.hu Mullard Space Science Laboratory, University College London, UK Observatoire de Paris, LESIA, CNRS, UPMC Univ. Paris 06, Univ. Paris-Diderot, Meudon Cedex, France
K. G. Strassmeier
Affiliation:
Leibniz Institute for Astrophysics Potsdam (AIP), Germany
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Abstract

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We present examples of activity cycle timescales on different types of stars from lowmass dwarfs to more massive giants, with wide-ranging rotation rates, and compare the observed cyclicities to the irradiance based solar cycle and its modulations. Using annual spectral solar irradiance in wavelength bands typical for stellar observations reconstructed by Shapiro et al. (2011), a direct comparison can be made between cycle timescales and amplitudes derived for the Sun and the stars. We show that cycles on multiple timescales, known to be present in solar activity, also show up on stars when the dataset is long enough to allow recognition. The cycle lengths are not fixed, but evolve – gradually during some periods but there are also changes on short timescales. In case the activity is dominated by spots, i.e., by cooler surface features, the star is redder when fainter, whereas other type of activity make the stars bluer when the activity is higher. We found the Sun to be a member of the former group, based on reconstructed spectral irradiance data by Shapiro et al. (2011).

Keywords

stars: activitystars: spotsSun: activitysunspots
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 7 , Symposium S286: Comparative Magnetic Minima: Characterizing quiet times in the Sun and Stars , October 2011 , pp. 279 - 285
Copyright
Copyright © International Astronomical Union 2012

References

Baliunas, S., Nesme-Ribes, E., Sokoloff, D., & Soon, W. 1996 ApJ 460, 848CrossRefGoogle Scholar
Brown, B. P., Miesch, M. S., Browning, M. K. et al. , 2011 ApJ 731, 69BCrossRefGoogle Scholar
Frick, P., Soon, W., Popova, E., & Baliunas, S. 2004 New Astron. 9, 599CrossRefGoogle Scholar
Judge, P. G. & Thompson, M. J. 2012 this proceedingsGoogle Scholar
Kolláth, Z. & Oláh, K. 2009, A&A 501, 695Google Scholar
Kolláth, Z., Oláh, K., & van Driel-Gesztelyi, L. 2011, this proceedingsGoogle Scholar
Messina, S. & Guinan, E. F. 2008, A&A 393, 255Google Scholar
Messina, S. 2008, A&A 480, 495Google Scholar
Oláh, K., Kolláth, Z., Granzer, T. et al. , 2009, A&A 501, 703Google Scholar
Preminger, D., Chapman, G. A., & Cookson, A. M. 2011, ApJ 739, L45CrossRefGoogle Scholar
Shapiro, A. I., Schmutz, W., Rozanov, E. et al. , 2011, A&A 529A, 67SGoogle Scholar
Strassmeier, K. G., Boyd, L. J., Epand, D. H., & Granzer, Th. 1997, PASP 109, 697CrossRefGoogle Scholar
Wilson, O. C. 1968, ApJ 153, 221CrossRefGoogle Scholar