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arXiv · 1608.08741

Chandra View of Magnetically Confined Wind in HD191612: Theory versus Observations

Yael Naze·Asif ud-Doula·Svetozar A. Zhekov
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Abstract

High-resolution spectra of the magnetic star HD191612 were acquired using the Chandra X-ray observatory at both maximum and minimum emission phases. We confirm the flux and hardness variations previously reported with XMM-Newton, demonstrating the great repeatability of the behavior of HD191612 over a decade. The line profiles appear typical for magnetic massive stars: no significant line shift, relatively narrow lines for high-Z elements, and formation radius at about 2R*. Line ratios confirm the softening of the X-ray spectrum at the minimum emission phase. Shift or width variations appear of limited amplitude at most (slightly lower velocity and slightly increased broadening at minimum emission phase, but within 1--2 sigma of values at maximum). In addition, a fully self-consistent 3D magnetohydrodynamic (MHD) simulation of the confined wind in HD191612 was performed. The simulation results were directly fitted to the data leading to a remarkable agreement overall between them.

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Yael Naze, Asif ud-Doula, Svetozar A. Zhekov. 2016-08-31. Chandra View of Magnetically Confined Wind in HD191612: Theory versus Observations. https://doi.org/10.3847/0004-637x%2F831%2F2%2F138

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