No detection of large-scale magnetic fields at the surfaces of Am and HgMn stars

  title={No detection of large-scale magnetic fields at the surfaces of Am and HgMn stars},
  author={Michel Auri{\`e}re and Gregg A. Wade and François Lignières and Alain Hui-Bon-Hoa and John D. Landstreet and Ilian T. Iliev and Jean-François Donati and Pascal Petit and T. Roudier and Sylvie Th{\'e}ado},
  journal={Astronomy and Astrophysics},
Aims. We investigate the magnetic dichotomy between Ap/Bp and other A-type stars by carrying out a deep spectropolarimetric study of Am and HgMn stars. Methods. Using the NARVAL spectropolarimeter at the Telescope Bernard Lyot (Observatoire du Pic du Midi, France), we obtained high-resolution circular polarisation spectroscopy of 12 Am stars and 3 HgMn stars. Results. Using least squares deconvolution (LSD), no magnetic field is detected in any of the 15 observed stars. Uncertaintiies as low as… 

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