Magnetic cycles of the planet-hosting star τ Bootis – II. A second magnetic polarity reversal

  title={Magnetic cycles of the planet-hosting star $\tau$ Bootis – II. A second magnetic polarity reversal},
  author={R Fares and Jean-François Donati and Claire Moutou and David Bohlender and Claude Catal{\`a} and Magali Deleuil and Evgenya L. Shkolnik and Andrew Collier Cameron and M. M. Jardine and Gordon Arthur Hunter Walker},
  journal={Monthly Notices of the Royal Astronomical Society},
In this paper, we present new spectropolarimetric observations of the planet- hosting starBootis, using ESPaDOnS and Narval spectropolarimeters at Canada- France-Hawaii Telescope (CFHT) and Telescope Bernard Lyot (TBL), respectively. We detected the magnetic field of the star at three epochs in 2008. It is a weak magnetic field of only a few Gauss, oscillating between a predominant toroidal com- ponent in January and a dominant poloidal component in June and July. A magnetic polarity reversal… Expand

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