The [ITAL]IUE[/ITAL] MEGA Campaign: The Rotationally Modulated Wind of ζ Puppis

Ian D. Howarth, Raman K. Prinja, Derck Massa
1995 Astrophysical Journal  
We discuss 16 days of intensive IUE observations of the Si IV doublet (1400) in the spectrum of the O4 I(n) f star Pup. The data show continuous variability throughout the greater part of the blueshifted absorption. Time series analysis of these data reveals significant power at periods of 19.2 hr and 5.2 days, which we identify with the mean recurrence time of "discrete absorption components" (DACs) and the photospheric rotation period, respectively. These results indicate that the wind has a
more » ... hat the wind has a global longitudinal asymmetry (approaching a factor 2 in optical depth), possibly associated with large-scale magnetic structures, but suggest that the DACs are not directly associated with specific stellar longitudes in this star. There is no significant power in the lines at the 8.5 hr period identified in photospheric absorption-line variability, nor at the 16.7 hr period reported in X-ray observations.
doi:10.1086/309710 fatcat:eunfbfuv6jgrfhy5shctnaxkhq