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Results of Coordinated Multiwavelength Observations of Solar-Type Stars

Published online by Cambridge University Press:  08 February 2017

J. Huovelin  and
S.H. Saar
J. Huovelin
Affiliation:
Observatory and Astrophysics Laboratory, University of Helsinki, Tähtitorninmäki, SF-00130 Helsinki, Finland
S.H. Saar
Affiliation:
Harvard-Smithsonian Center for Astrophysics, Mail Stop 58, 60 Garden Street, Cambridge, MA 02138, USA

Abstract

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We present results of nearly simultaneous polarimetric and Ca II(H+K) emission observations taken over a full rotation period for a sample of six solar-type stars. Significant variations are seen for two stars in polarization and four stars in Ca emission, which we interpret as due to rotational modulation of magnetic areas on the stellar surface. The irregularity of the variations suggest changes of the area size and/or distribution in time scales of the rotation period. Preliminary models (including rough surface maps of two stars) and future prospects are discussed.

Type
VII. Convection and Magnetic Fields in Solar-type Stars
Information
Symposium - International Astronomical Union , Volume 138: Solar Photosphere: Structure, Convection and Magnetic Fields , 1990 , pp. 443 - 446
Copyright
Copyright © Kluwer 1990 

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