Discovery of a weak magnetic field in the photosphere of the single giant Pollux

  title={Discovery of a weak magnetic field in the photosphere of the single giant Pollux},
  author={Michel Auri{\`e}re and Gregg A. Wade and Renada K. Konstantinova-Antova and Corinne Charbonnel and Claude Catal{\`a} and Werner W. Weiss and T. Roudier and P. Petit and Jean-François Donati and Evelyne Alecian and R{\'e}mi Cabanac and Sophie Van Eck and C P Folsom and Jennifer Power},
  journal={Astronomy and Astrophysics},
Aims. We observe the nearby, weakly-active single giant, Pollux, in order to directly study and infer the nature of its magnetic field. Methods. We used the new generation spectropolarimeters ESPaDOnS and NARVAL to observe and detect circular polarization within the photospheric absorption lines of Pollux. Our observations span 18 months from 2007–2009. We treated the spectropolarimetric data using the Least-Squares Deconvolution method to create high signal-to-noise ratio mean Stokes V… Expand

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