论文标题
明亮的RRC星的光谱和光度法时间序列
Spectroscopic and photometric time series of the bright RRc star T Sex
论文作者
论文摘要
我们介绍了最亮的北RRC恒星之一T SEX的光谱时间序列观测。此外，我们还分析了扩展的光度数据集，尤其是最近对苔丝空间望远镜的观察结果。我们研究的主要发现如下：t性，与所有分析空间光度法的RRC恒星不同，仅显示$ 0.5F_X $频率作为额外的脉动频率。这样，T性可能是从空间光度法中发现的如此稀有的RRC恒星的第一个代表。光谱数据表明，与脉动阶段有关H $α$线的周期性变形。尚未报道任何RR Lyre恒星的现象。特征线失真可能是由湍流对流引起的，这使得与典型的RRRAB恒星相比，t性的大型速度更高。在0.37和0.80脉动阶段观察到了Na D线的线倍加倍。这种现象的解释是，两个吸收成分来自不同的来源。红色组件来自恒星的脉动气氛，而蓝色的恒星来自星际空间。在0.438阶段，我们在Na D线上检测到发射，这可能表明弱冲击波。
We present spectroscopic time series observations on one of the brightest northern RRc star, T Sex. Additionally, we also analysed extended photometric data sets, particularly the recent observations of the TESS space telescope. The main findings of our studies are as follows: T Sex, unlike all RRc stars whose space photometry has been analysed, shows only the $0.5f_x$ frequency as an additional pulsation frequency. With this, T Sex may be the first represent of such rare RRc stars found from space photometry. The spectroscopic data show a periodic distortion of the H$α$ line with the pulsation phase. This phenomenon has not been reported for any RR Lyrae stars. The characteristic line distortion is probably caused by the turbulent convection, which resulted in higher macroturbulent velocity for T Sex than for typical RRab stars. Line doubling of the Na D line was observed between the 0.37 and 0.80 pulsation phases. The explanation of this phenomenon is that the two absorption components originate from different sources. The redder component comes from the pulsating atmosphere of the star, while the bluer one from the interstellar space. At phase 0.438, we detected emission on the Na D line, which may indicate a weak shock wave.
