论文标题
EPIC 216747137：一种新的HW Vir Eclips-lips lips lips-sdob初级和低质量M-warf伴侣
EPIC 216747137: a new HW Vir eclipsing binary with a massive sdOB primary and a low-mass M-dwarf companion
论文作者
论文摘要
Epic 216747137是开普勒飞船在其K2“第二人生”中发现的一种新的HW〜Virginis系统。与其他HW Vir Systems一样，Epic 216747137是一种固定后的Envelope二进制二进制，由热糖星和凉爽的低质量伴侣组成。 3.87小时的短轨道周期产生了次级的强反射效应（在R频段中约为9％）。 EPIC 216747137与AA DOR和V1828 AQL一起属于具有热进化的SDOB主要的HW VIR Systems的一个小亚组。我们找到了热点组件的以下大气参数：teff = 40400 $ \ pm $ 1000 k，logg = 5.56 $ \ pm $ 0.06，log（n（he）/n（h））= $ - $ - $ 2.59 $ \ pm $ 0.05。 SDOB旋转速度vsini = 51 $ \ pm $ 10 km/s表示恒星旋转比轨道革命慢，并且系统不同步。当我们将光度法和光谱结果与Gaia视差结合在一起时，该系统的最佳解决方案对应于质量约0.62 msun的主要解决方案，并且可能超过中央氦气耗尽，而凉爽的M-Warf Companion则质量约为0.11 msun。
EPIC 216747137 is a new HW~Virginis system discovered by the Kepler spacecraft during its K2 "second life". Like the other HW Vir systems, EPIC 216747137 is a post-common-envelope eclipsing binary consisting of a hot subluminous star and a cool low-mass companion. The short orbital period of 3.87 hours produces a strong reflection effect from the secondary (~9% in the R band). Together with AA Dor and V1828 Aql, EPIC 216747137 belongs to a small subgroup of HW Vir systems with a hot evolved sdOB primary. We find the following atmospheric parameters for the hot component: Teff=40400$\pm$1000 K, logg=5.56$\pm$0.06, log(N(He)/N(H))=$-$2.59$\pm$0.05. The sdOB rotational velocity vsini=51$\pm$10 km/s implies that the stellar rotation is slower than the orbital revolution and the system is not synchronized. When we combine photometric and spectroscopic results with the Gaia parallax, the best solution for the system corresponds to a primary with a mass of about 0.62 Msun close to, and likely beyond, the central helium exhaustion, while the cool M-dwarf companion has a mass of about 0.11 Msun.
