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Magnetic activity of cool stars in the Hertzsprung-Russell diagram

Published online by Cambridge University Press:  05 July 2012

J. H. M. M. Schmitt
J. H. M. M. Schmitt*
Affiliation:
Hamburger Sternwarte, 21029 Hamburg, Gojenbergsweg 112, Germany email: [email protected]
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Abstract

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I review the X-ray emission from cool stars with outer convection zones in comparison to the Sun with a focus on the properties of low-activity stars. I present the recent results of long-term X-ray monitoring which demonstrate the existence of X-ray cycles on stars with known calcium cycles. The evidence of a minimum stellar X-ray flux is presented and arguments are put forward for the view that the Sun in its extended minimum between 2008 - 2009 behaved very much like a Maunder-minimum Sun.

Keywords

Sun: activitystars: activitystars: coronaeX-rays: stars
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. 296 - 306
Copyright
Copyright © International Astronomical Union 2012

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