论文标题
TICS 167692429和220397947:第一个紧凑型等级三星星用苔丝发现
TICs 167692429 and 220397947: The first compact hierarchical triple stars discovered with TESS
论文作者
论文摘要
我们报告了第一年在其南部或附近发现的前两个紧凑型分层三星级的发现和复杂分析。系统,也来自日食深度变化。我们进行了全面的分析,包括苔丝和档案地面WASP灯曲面的同时光动力模型,以及日食的时机变化曲线。同样,考虑到GAIA DR2可视性和分类金属性,我们首次将我们同时纳入了多个恒星光谱分布数据和理论parsec恒星等速线。我们发现这两个系统都有双F-Star二进制组和较低的大量三级恒星。在TIC 167692429系统中,相对于外部轨道,内部二进制是适度倾斜的($ i_ {mut} = 27^o $),而二进制(三重)轨道周期分别为10.3对331天。相互倾斜的轨道会导致二进制轨道平面的驱动进动,从而导致二进制蚀的长时间消失。在TIC 220397947中,两个轨道平面更接近对齐,并且内轨道和外轨道周期分别为3.5天和77天。在没有径向速度观察的情况下,我们无法计算两个系统的高度准确质量和年龄。根据Stellar Insochrones TIC 167692429的说法,可能是预先序列或较旧的后MS系统。在TIC 220397947中,我们的解决方案更喜欢年轻的预MS场景。
We report the discovery and complex analyses of the first two compact hierarchical triple star systems discovered with TESS in or near its southern continuous viewing zone during Year 1. Both TICs 167692429 and 220397947 were previously unknown eclipsing binaries, and the presence of a third companion star was inferred from eclipse timing variations exhibiting signatures of strong 3rd-body perturbations and, in the first system, also from eclipse depth variations. We carried out comprehensive analyses, including the simultaneous photodynamical modelling of TESS and archival ground-based WASP lightcurves, as well as eclipse timing variation curves. Also, for the first time, we included in the simultaneous fits multiple star spectral energy distribution data and theoretical PARSEC stellar isochrones, taking into account Gaia DR2 parallaxes and cataloged metallicities. We find that both systems have twin F-star binaries and a lower mass tertiary star. In the TIC 167692429 system the inner binary is moderately inclined ($i_{mut}=27^o$) with respect to the outer orbit, and the binary vs. outer (triple) orbital periods are 10.3 vs. 331 days, respectively. The mutually inclined orbits cause a driven precession of the binary orbital plane which leads to the disappearance of binary eclipses for long intervals. In the case of TIC 220397947 the two orbital planes are more nearly aligned and the inner vs. outer orbital periods are 3.5 and 77 days, respectively. In the absence of radial velocity observations, we were unable to calculate highly accurate masses and ages for the two systems. According to stellar isochrones TIC 167692429 might be either a pre-main sequence or an older post-MS system. In the case of TIC 220397947 our solution prefers a young, pre-MS scenario.