Anti-solar differential rotation on the active K-giant σ Geminorum (Research Note)

Zs Kovári, J. Bartus, K. G. Strassmeier, K. Vida, M. Švanda, K. Oláh

Research output: Contribution to journalArticle

23 Citations (Scopus)


The active K1 giant σ Gem and its differential surface rotation is revisited. We refine our previous inconclusive result by recovering the spot migration pattern of this long-period RS CVn-type binary through application of the technique of "average cross-correlation of contiguous Doppler images" to a set of six Doppler images from 3.6 consecutive rotation cycles. We find an anti-solar differential rotation law with a shear of α ≈ -0.022 ±0.006. We also find evidence of a poleward migration trend of spots with an average velocity of ≈ 300 ms-1.

Original languageEnglish
Pages (from-to)165-168
Number of pages4
JournalAstronomy and Astrophysics
Issue number1
Publication statusPublished - Oct 1 2007



  • Stars: activity
  • Stars: imaging
  • Stars: individual: σGeminorum
  • Stars: late-type
  • Stars: starspots

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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