论文标题
苔丝没有氢缺乏二进制
TESS uncloaks the secondaries in hydrogen-deficient binaries
论文作者
论文摘要
$ \ UPSILON $ SGR是四个已知氢（HDB）系统的原型。这些特征在于缺乏氢的A型原发性，可变的氢发射线，而通常看不见的次级被认为是上主序列的恒星。轨道周期范围从数十天到360 d。所有四个HDB的苔丝观察结果均显示出通量的变化，定义明确的周期在0.5-0.9 d的范围内，太短了，无法与超级初级相关，更有可能是次要的旋转周期，并且与化学表面不对称或低阶非降低非速率振荡有关。观察到的旋转期支持对$ \ upsilon $ sgr中学的最新分析。这些观察结果可以直接瞥见所有四个系统中的次级，并应有助于解释如何剥离主要的低质量氢残留物。
$\upsilon$ Sgr is the prototype of four known hydrogen-deficient binary (HdB) systems. These are characterised by a hydrogen-deficient A-type primary, variable hydrogen emission lines, and a normally unseen secondary presumed to be an upper main-sequence star. Orbital periods range from tens of days to 360 d. TESS observations of all four HdBs show a flux variation with well-defined period in the range 0.5 -- 0.9 d, too short to be associated with the supergiant primary, and more likely to be the rotation period of the secondary and associated with a chemical surface asymmetry or a low-order non-radial oscillation. The observed rotation period supports a recent analysis of the $\upsilon$ Sgr secondary. The observations give a direct glimpse of the secondary in all four systems, and should help to explain how the primary has been stripped to become a low-mass hydrogen remnant.
