Absctract—The present study continues the investigation of the super-fast variability of line profiles in the spectra of stars of early spectral types. We studied the line-profile variability in the spectrum of the binary (O9.7Ib+B0III) star \(\zeta \) Ori A using the MSS spectrograph of the 6-m BTA telescope based on observations carried out on February 19, 2019. Short-period regular variations of the hydrogen Balmer lines and He I lines with periods from 89 to 295 minutes were found. The presence of short-period variations in the period interval of 10–20 minutes is also possible. An analysis of the stellar brightness variations from observations by the TESS satellite showed the presence of seven regular components, one of which is probably the second harmonic of the rotation period of the main component of the Aa star \(\zeta \) Ori A. The magnetic field of the star was determined for the whole series of observations. The longitudinal component of the root-mean-square magnetic field measured by the regression method over the whole observation period is \(49\) G.

摘要——本研究继续研究早期光谱类型恒星光谱中线轮廓的超快速变化。我们研究了双星 (O9.7Ib+B0III) 恒星\(\zeta \)Ori A 使用基于 2019 年 2 月 19 日进行的观测的 6 米 BTA 望远镜的 MSS 光谱仪。 发现了周期为 89 到 295 分钟的氢巴尔默线和 He I 线的短期规则变化。在 10-20 分钟的周期间隔中也可能存在短期变化。TESS卫星对恒星亮度变化的分析表明存在七个规则分量，其中一个可能是Aa星\(\zeta\) Ori A主分量自转周期的二次谐波。在整个系列观测中确定了恒星的磁场。回归法测得的整个观测周期均方根磁场的纵向分量为\(49\) G.