Pollux: a stable weak dipolar magnetic field but no planet?

  title={Pollux: a stable weak dipolar magnetic field but no planet?},
  author={Michel Auri{\`e}re and Renada Konstantinova-Antova and O. Espagnet and Pascal Petit and T. Roudier and Corinne Charbonnel and Jean-François Donati and Gregg A. Wade},
  journal={Proceedings of the International Astronomical Union},
  pages={359 - 362}
Abstract Pollux is considered as an archetype of a giant star hosting a planet: its radial velocity (RV) presents sinusoidal variations with a period of about 590 d, which have been stable for more than 25 years. Using ESPaDOnS and Narval we have detected a weak (sub-gauss) magnetic field at the surface of Pollux and followed up its variations with Narval during 4.25 years, i.e. more than for two periods of the RV variations. The longitudinal magnetic field is found to vary with a sinusoidal… 

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