Abstract

We present the first high accuracy UBVRI(RI)c CCD light curves of the poorly investigated eclipsing system V680 Mon = GSC 7428 218 (P = 8.54^d, V = 10.02^m). They were used to find the photometric solutions and to derive the physical characteristics of the components. The highest known eccentricity e = 0.613 was found in the class of systems with eccentric orbits. The orientation of the orbital ellipse ω = 357° is not convenient for apsidal motion investigation. High accuracy of our observations allows to find the reliable parameters of the system: M₁ = 3.3\({{M}_{ \odot }}\) (B7 V), M₂ = 1.8\({{M}_{ \odot }}\) (A2 V). We estimate the age of the components to be 70 mega-years. The photometric parallax π = 0.00109(1)″, derived from our observations, is two times smaller than the value π = 0.0025(9)″ from GAIA DR1, affected by the presence of the K3 V optical companion of the investigated star. The light curves solution demonstrates the presence of a third light, which can be assigned to a star of A4 V spectral class. The light time effect is found in the minima timings, so the source of the third light is physically connected to the eclipsing system. The parameters of the third body orbit are derived.

中文翻译：

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已知最高偏心率的V680单月环星的物理参数

摘要

我们提出了未经充分研究的日蚀系统V680 Mon = GSC 7428 218（P = 8.54 ^d，V = 10.02 ^m）的第一条高精度UBVRI（RI）c CCD光曲线。它们用于查找光度学解决方案并导出组件的物理特性。在具有偏心轨道的系统类别中发现了最高的已知偏心率e = 0.613。轨道椭圆ω= 357°的方向不便于进行原子运动研究。我们的观测值的高精度可以找到系统的可靠参数：M ₁ = 3.3 \（{{M} _ {\ odot}} \）（B7 V），M ₂ = 1.8 \（{{M} _ {\ odot}} \）（A2 V）。我们估计组件的寿命为70兆年。从我们的观测中得出的光度视差π= 0.00109（1）''比GAIA DR1的值π= 0.0025（9）''小两倍，这是受研究恒星的K3 V光学伴侣的影响所致。光曲线解决方案演示了第三束光的存在，可以将其分配给A4 V光谱类别的一颗恒星。在最短的时间中发现了光时间效应，因此第三光的光源物理连接到日食系统。推导出第三体轨道的参数。