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arXiv · 0812.2356

Magnetic fields, winds and X-rays of massive stars in the Orion Nebula Cluster

V. Petit·G. A. Wade·L. Drissen·T. Montmerle·E. Alecian
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Abstract

In massive stars, magnetic fields are thought to confine the outflowing radiatively-driven wind, resulting in X-ray emission that is harder, more variable and more efficient than that produced by instability-generated shocks in non-magnetic winds. Although magnetic confinement of stellar winds has been shown to strongly modify the mass-loss and X-ray characteristics of massive OB stars, we lack a detailed understanding of the complex processes responsible. The aim of this study is to examine the relationship between magnetism, stellar winds and X-ray emission of OB stars. In conjunction with a Chandra survey of the Orion Nebula Cluster, we carried out spectropolarimatric ESPaDOnS observations to determine the magnetic properties of massive OB stars of this cluster.

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V. Petit, G. A. Wade, L. Drissen, T. Montmerle, E. Alecian. 2008-12-12. Magnetic fields, winds and X-rays of massive stars in the Orion Nebula Cluster. https://doi.org/10.1017/s174392130903110x

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