论文标题
白矮人二进制途径调查III：含有白矮人的分层三元组的污染
The White Dwarf Binary Pathways Survey III: contamination from hierarchical triples containing a white dwarf
论文作者
论文摘要
白矮二进制途径调查旨在增加与白色矮人同伴（WD+AFGK二进制文件）中已知的A，F，G和K主序列星的数量，以完善我们对紧凑型二元二元进化的理解和超新星的性质。这些近距离WD+AFGK二元星有望通过共同的包膜演化形成，其中潮汐力倾向于绕轨道循环。但是，一些已鉴定的WD+AFGK二进制候选物显示出偏心轨道，表明这些系统要么是通过不同的机制形成的，要么可能不是关闭WD+AFGK二进制文件。我们观察到这些古怪的WD+AFGK二进制组之一，发现系统TYC 7218-934-1实际上是一个三重系统，其中WD是遥远的伴侣。内部二进制可能由G型恒星以及在怪异轨道中看不见的低质量伴侣组成。基于这一发现，我们估计可能污染WD+AFGK样品的三重系统的比例。我们发现，轨道周期短的目标少于100天的目标不到15％，这可能是分层的三元组。
The White Dwarf Binary Pathways Survey aims at increasing the number of known detached A, F, G and K main sequence stars in close orbits with white dwarf companions (WD+AFGK binaries) to refine our understanding about compact binary evolution and the nature of Supernova Ia progenitors. These close WD+AFGK binary stars are expected to form through common envelope evolution, in which tidal forces tend to circularize the orbit. However, some of the identified WD+AFGK binary candidates show eccentric orbits, indicating that these systems are either formed through a different mechanism or perhaps they are not close WD+AFGK binaries. We observed one of these eccentric WD+AFGK binaries with SPHERE and find that the system TYC 7218-934-1 is in fact a triple system where the WD is a distant companion. The inner binary likely consists of the G-type star plus an unseen low mass companion in an eccentric orbit. Based on this finding, we estimate the fraction of triple systems that could contaminate the WD+AFGK sample. We find that less than 15 per cent of our targets with orbital periods shorter than 100 days might be hierarchical triples.
