The Magnetic Fields at the Surface of Active Single G-K Giants

  title={The Magnetic Fields at the Surface of Active Single G-K Giants},
  author={Michel Auri{\`e}re and Renada Konstantinova-Antova and Corinne Charbonnel and Gregg A. Wade and Svetla Tsvetkova and Pascal Petit and Boris Dintrans and Natalia A. Drake and Thibaut Decressin and Nad{\`e}ge Lagarde and Jean-François Donati and T. Roudier and François Lignières and Klaus-Peter Schroder and John D. Landstreet and A. L{\`e}bre and Werner W. Weiss and J-P. Zahn},
  journal={arXiv: Solar and Stellar Astrophysics},
We investigate the magnetic field at the surface of 48 red giants selected as promising for detection of Stokes V Zeeman signatures in their spectral lines. We use the spectropolarimeters Narval and ESPaDOnS to detect circular polarization within the photospheric absorption lines of our targets and use the least-squares deconvolution (LSD) method. We also measure the classical S-index activity indicator, and the stellar radial velocity. To infer the evolutionary status of our giants and to… 
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