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arXiv · 2211.09849

Discrete Absorption Components from 3-D spot models of hot star winds

F. A. Driessen·N. D. Kee
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Abstract

The winds of hot, massive stars are variable from processes happening on both large and small spatial scales. A particular case of such wind variability is 'discrete-absorption components' (DACs) that manifest themselves as outward moving density features in UV resonance line spectra. Such DACs are believed to be caused by large-scale spiral-shaped density structures in the stellar wind. We consider novel 3-D radiation-hydrodynamic models of rotating hot star winds and study the emergence of co-rotating spiral structures due to a local (pseudo-)magnetic spot on the stellar surface. Subsequently, the hydrodynamic models are used to retrieve DAC spectral signatures in synthetic UV spectra created from a 3-D short characteristics radiative transfer code.

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F. A. Driessen, N. D. Kee. 2022-11-17. Discrete Absorption Components from 3-D spot models of hot star winds. https://arxiv.org/abs/2211.09849

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