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Magnetic fields of B and Herbig Ae stars measured with FORS1 at the VLT

S. Hubrig·T. Szeifert·P. North·M. Schoeller·R. V. Yudin
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Abstract

We present the results of a magnetic survey with FORS1 in polarimetric mode of a sample of B and Herbig Ae stars with previously undetected magnetic fields. For the first time a mean longitudinal magnetic field at a level higher than 3 sigma has been detected in one normal B star, two HgMn stars, one PGa star and four SPB stars. The observations of the three Herbig Ae stars (also known as Vega-like stars) reveal a definite longitudinal magnetic field in the star HD139614 at 4.8 sigma level: =-450+-93 G. This is the largest magnetic field ever diagnosed for a Herbig Ae star. A hint of a magnetic field is found in the other two stars, HD144432 and HD144668, for which magnetic fields are measured at the ~1.6 sigma and ~2.5 sigma level respectively.

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S. Hubrig, T. Szeifert, P. North, M. Schoeller, R. V. Yudin. 2005-01-23. Magnetic fields of B and Herbig Ae stars measured with FORS1 at the VLT. https://arxiv.org/abs/astro-ph/0501495

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