Magnetic activity in late-type giant stars: Numerical MHD simulations of non-linear dynamo action in Betelgeuse

  title={Magnetic activity in late-type giant stars: Numerical MHD simulations of non-linear dynamo action in Betelgeuse},
  author={S{\o}ren Bertil F. Dorch},
  journal={Astronomy and Astrophysics},
  • S. Dorch
  • Published 13 March 2004
  • Physics
  • Astronomy and Astrophysics
Evidence is presented from numerical magneto-hydrodynamical simulations for the existence of magnetic activity in late-type giant stars. A red supergiant with stellar parameters similar to that of Betelgeuse (α Orionis) is modeled as a "star- in-a-box" with the high-order "Pencil Code". Both linear kinematic and non-linear saturated dynamo action are possible: the non-linear magnetic field saturates at a super-equipartition value corresponding to surface magnetic field of field strengths up to… 

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