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Discovery of magnetic fields in hot subdwarfs

S. J. O'Toole·S. Jordan·S. Friedrich·U. Heber
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Abstract

We present initial results of a project to measure mean longitudinal magnetic fields in a group of sdB/OB/O stars. The project was inspired by the discovery of three super-metal-rich sdOB stars, each having metals (e.g. Ti, V) enhanced by factors of 10^3 to 10^5. Similar behaviour is observed in chemically peculiar A stars, where strong magnetic fields are responsible for the enrichment. With this in mind, we obtained circularly polarised spectra of two of the super-metal-rich sdOBs, two "normal" sdBs and two sdOs using FORS1 on the ESO/VLT. By examining circular polarisation in the hydrogen Balmer lines and in helium lines, we have detected magnetic fields with strengths of 1-2 kG in most of our targets. This suggests that such fields are relatively common in hot subdwarfs.

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S. J. O'Toole, S. Jordan, S. Friedrich, U. Heber. 2004-10-02. Discovery of magnetic fields in hot subdwarfs. https://arxiv.org/abs/astro-ph/0410042

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