Results Of Coordinated Multiwavelength Observations Of Solar-Type Stars

  • J. Huovelin
  • S. H. Saar
Part of the International Astronomical Union book series (IAUS, volume 138)


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.


Crimean Astrophysical Observatory Stellar Surface Magnetic Area Research Fellowship Program Emission Observation 
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Copyright information

© International Astronomical Union 1990

Authors and Affiliations

  • J. Huovelin
    • 1
  • S. H. Saar
    • 2
  1. 1.Observatory and Astrophysics LaboratoryUniversity of HelsinkiHelsinkiFinland
  2. 2.Harvard-Smithsonian Center for AstrophysicsCambridgeUSA

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