The magnetic field of Betelgeuse: a local dynamo from giant convection cells?

  title={The magnetic field of Betelgeuse: a local dynamo from giant convection cells?},
  author={Michel Auri{\`e}re and Jean-François Donati and Renada K. Konstantinova-Antova and Guy Perrin and Pascal Petit and T. Roudier},
  journal={Astronomy and Astrophysics},
Context. Betelgeuse is an M supergiant with a complex and extended atmosphere, which also harbors spots and giant granules at its surface. A possible magnetic field could contribute to the mass loss and to the heating of the outer atmosphere. Aims. We observed Betelgeuse, to directly study and infer the nature of its magnetic field. Methods. We used the new-generation spectropolarimeter NARVAL and the least square deconvolution (LSD) method to detect circular polarization within the… 

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