B fields in OB stars (BOB): on the detection of weak magnetic fields in the two early B-type stars beta CMa and epsilon CMa Possible lack of a "magnetic desert" in massive stars

  title={B fields in OB stars (BOB): on the detection of weak magnetic fields in the two early B-type stars beta CMa and epsilon CMa Possible lack of a "magnetic desert" in massive stars},
  author={Luca Fossati and Norberto Castro and Thierry Morel and Norbert Langer and Maryline Briquet and Thorsten A. Carroll and Swetlana Hubrig and M. Fernanda Nieva and Lidia M Oskinova and Norbert Przybilla and Fabian R N Schneider and Markus Scholler and Sergio Sim{\'o}n-D{\'i}az and Ilya Ilyin and Alex de Koter and Andreas Reisenegger and Hugues Sana and the Bob collaboration},
  journal={Astronomy and Astrophysics},
Only a small fraction of massive stars seem to host a measurable structured magnetic field, whose origin is still unknown and whose implications for stellar evolution still need to be assessed. Within the context of the "B fields in OB stars (BOB)" collaboration, we used the HARPSpol spectropolarimeter to observe the early B-type stars β CMa (HD 44743; B1 II/III) andCMa (HD 52089; B1.5II) in December 2013 and April 2014. For both stars, we consistently detected the signature of a weak (<30 G in… Expand
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