Detection of a weak surface magnetic field on Sirius A: are all tepid stars magnetic?

  title={Detection of a weak surface magnetic field on Sirius A: are all tepid stars magnetic?},
  author={Pascal Petit and François Lignières and Michel Auri{\`e}re and Gregg A. Wade and Dana Alina and J{\'e}r{\^o}me Ballot and Torsten Bohm and Laur{\`e}ne Jouve and Apurva V. Oza and F. Paletou and Sylvie Th'eado},
  journal={Astronomy and Astrophysics},
Aims. We aim at a highly sensitive search for weak magnetic fields in main sequence stars of intermediate mass, by scanning classes of stars with no previously reported magnetic members. After detecting a weak magnetic field on the normal, rapidly rotating A-type star Vega, we concentrate here on the bright star Sirius A, taken as a prototypical, chemically peculiar, moderately rotating Am star. Methods. We employed the NARVAL and ESPaDOnS high-resolution spectropolarimeters to collect 442… 

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