论文标题
了解K2目标的旋转变异性。 HGMN Star KIC 250152017和蓝色水平分支星星KIC 249660366
Understanding the rotational variability of K2 targets. HgMn star KIC 250152017 and blue horizontal branch star KIC 249660366
论文作者
论文摘要
超脑空间光度法使我们能够揭示光变性，即使在先前被认为是常数的恒星中也可以揭示光变性。一大群此类恒星显示可能在旋转调制的变化。这种类型的光变异性具有特殊的兴趣，因为它提供了旋转速率的精确估计。我们旨在了解显示旋转调制标志的K2目标的光变异性的起源。我们使用相位分辨率的Xshooter光谱法来了解恒星KIC 〜250152017和KIC 〜249660366的光变异性，这些变化可能是旋转调制的。我们确定了单个相处的大气参数，并测试了光谱中旋转调制的存在。 KIC 250152017是HGMN恒星，其光变异性是由锰和铁的不均匀表面分布引起的。它只是第二个HGMN恒星，其光变异性得到充分理解。 KIC 249660366是一颗湿润的高速水平分支恒星，硅和氩气超过了。该恒星的光变化可能是由于此后封装二进制二进制中的反射效应引起的。
Ultraprecise space photometry enables us to reveal light variability even in stars that were previously deemed constant. A large group of such stars show variations that may be rotationally modulated. This type of light variability is of special interest because it provides precise estimates of rotational rates. We aim to understand the origin of the light variability of K2 targets that show signatures of rotational modulation. We used phase-resolved medium-resolution XSHOOTER spectroscopy to understand the light variability of the stars KIC~250152017 and KIC~249660366, which are possibly rotationally modulated. We determined the atmospheric parameters at individual phases and tested the presence of the rotational modulation in the spectra. KIC 250152017 is a HgMn star, whose light variability is caused by the inhomogeneous surface distribution of manganese and iron. It is only the second HgMn star whose light variability is well understood. KIC 249660366 is a He-weak, high-velocity horizontal branch star with overabundances of silicon and argon. The light variability of this star is likely caused by a reflection effect in this post-common envelope binary.
