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arXiv · 1204.4267

Magnetometry of a sample of massive stars in Carina

Y. Naze·S. Bagnulo·V. Petit·T. Rivinius·G. Wade·G. Rauw·M. Gagne
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Abstract

X-ray surveys of the Carina nebula have revealed a few hard and luminous sources associated with early-type stars. Such unusual characteristics for the high-energy emission may be related to magnetically-confined winds. To search for the presence of magnetic fields in these objects, we performed a limited spectropolarimetric survey using the FORS instrument. The multi-object mode was used, so that a total of 21 OB stars could be investigated during a one-night-long run. A magnetic field was detected in two objects of the sample, with a 6 sigma significance; Tr16-22 and 13. Such a detection was expected for Tr16-22, as its X-ray emission is too bright, variable and hard, compared to other late-type O or O+OB systems. It is more surprising for Tr16-13, a poorly known star which so far has never shown any peculiar characteristics. Subsequent monitoring is now needed to ascertain the physical properties of these objects and enable a full modelling of their magnetic atmospheres and winds.

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Y. Naze, S. Bagnulo, V. Petit, T. Rivinius, G. Wade, G. Rauw, M. Gagne. 2012-04-19. Magnetometry of a sample of massive stars in Carina. https://doi.org/10.1111/j.1365-2966.2012.21134.x

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