论文标题
让两个伽玛CAS星有更多可变性
Let there be more variability in two gamma Cas stars
论文作者
论文摘要
我们研究了两种伽玛Cas类似物PI AQR和BZ CRU的短期光学变异性，这要归功于密集的地面光谱和太空传播光度监测。对于这两颗恒星，都检测到低振幅（MMAG）相干光度变异性。相关信号显示出长期振幅变化，如其他BE恒星。但是，这些信号出现在高频上，尤其是在PI AQR中，表明具有高度L的P模型，这是恒星中非常不寻常的特征。尽管BZ CRU仅显示低级光谱变异性，但没有明确的周期性，但pi aqr并非如此。在这颗星中，在截然不同的磁盘活性水平上进行的单独监测中，在光谱中确认了主要的光度频率（接近12/d）。光谱分析表明该模式可能具有镶嵌性质。
We investigate the short-term optical variability of two gamma Cas analogs, pi Aqr and BZ Cru, thanks to intensive ground-based spectroscopic and space-borne photometric monitorings. For both stars, low-amplitude (mmag) coherent photometric variability is detected. The associated signals display long-term amplitude variations, as in other Be stars. However, these signals appear at high frequencies, especially in pi Aqr, indicating p-modes with a high degree l, a quite unusual feature amongst Be stars. While BZ Cru presents only low-level spectral variability, without clear periodicity, this is not the case of pi Aqr. In this star, the dominant photometric frequencies, near ~12/d, are confirmed spectroscopically in separate monitorings taken during very different disk activity levels ; the spectroscopic analysis suggests a probable tesseral nature for the mode.
