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We present the results of a time-series analysis of 130 echelle spectra ofepsilon Ori (B0 Ia), acquired over seven observing seasons between 1998 and2006 at Ritter Observatory. The equivalent widths of Halpha (net) and He I 5876were measured and radial velocities were obtained from the central absorptionof He I 5876. Temporal variance spectra (TVS) revealed significant windvariability in both Halpha and He I 5876. The He I TVS have a double-peakedprofile consistent with radial velocity oscillations. A periodicity search wascarried out on the equivalent width and radial velocity data, as well as onwavelength-binned spectra. This analysis has revealed several periods in thevariability with time scales of 2-7 d. Many of these periods exhibit sinusoidalmodulation in the associated phase diagrams. Several of these periods werepresent in both Halpha and He I, indicating a possible connection between thewind and the photosphere. Due to the harmonic nature of these periods, stellarpulsations may be the origin of some of the observed variability. Periods onthe order of the rotational period were also detected in the He I line in the98-99 season and in both lines during the 04-05 season. These periods mayindicate rotational modulation due to structure in the wind.

Variability in Optical Spectra of epsilon Orionis