The influence of binarity on stellar activity

Research output: Contribution to journalArticle


Activity of late type stars is enhanced by fast rotation, which is maintained in nearly synchronized close binary systems. Magnetic activity originates in the deep convection zones of stars from where magnetic flux tubes emerge to their surfaces. The gravitational forces in binaries help the clustering of activity features giving rise to active longitudes. These preferred longitudes are observed in binaries from dwarfs to giants. Differential rotation is found in many active stars that are components of binary systems. If these binaries are circularized and nearly synchronized, then there will be a corotation latitude in their surfaces, and its position can be determined by observations and by theoretical calculations. Enhanced activity in binaries could have a reverse effect as well: strong magnetism in a binary component can modify the orbital period by the cyclic exchange of kinetic and magnetic energy in its convective envelope.

Original languageEnglish
Pages (from-to)442-452
Number of pages11
JournalProceedings of the International Astronomical Union
Issue numberS240
Publication statusPublished - Aug 2006



  • Stars: activity
  • Stars: atmospheres
  • Stars: binaries: close
  • Stars: late-type
  • Stars: magnetic fields
  • Stars: spots

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Astronomy and Astrophysics
  • Nutrition and Dietetics
  • Public Health, Environmental and Occupational Health
  • Space and Planetary Science

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