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arXiv · 0805.1864

Direct spectroscopic observations of clumping in O-star winds

Sebastien Lepine·Anthony F. J. Moffat
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Abstract

We report the detection and monitoring of transient substructures in the radiation-driven winds of five massive, hot stars in different evolutionary stages. Clumping in the winds of these stars shows up as variable, narrow subpeaks superposed on their wide, wind-broadened (optical) emission lines. Similar patterns of emission-line profile variations are detected in the Of stars zeta Puppis and HD93129A, in the more evolved hydrogen-rich, luminous, Of-like WN stars HD93131 and HD93162, and in the more mass-depleted WC star in gamma2 Velorum. These observations strongly suggest that stochastic wind clumping is a universal phenomenon in the radiation-driven, hot winds from all massive stars, with similar clumping factors in all stages of mass depletion.

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Sebastien Lepine, Anthony F. J. Moffat. 2008-05-13. Direct spectroscopic observations of clumping in O-star winds. https://doi.org/10.1088/0004-6256%2F136%2F2%2F548

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