Direct Spectroscopic Observations of Clumping in O - Star Winds
نویسنده
چکیده
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 ζ 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 γ2Velorum. These observations strongly suggest that stochastic wind clumping is a universal phenomenon in the radiationdriven, hot winds from all massive stars, with similar clumping factors in all stages of mass depletion. Subject headings: line:profiles – stars: emission-line, Be – stars: mass-loss – stars: winds, outflows – stars: Wolf-Rayet
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