标题： V994 Herculis五重系统的更新研究 显示英文标题

标题： Updated study of the quintuple system V994 Herculis

摘要： 目标：我们提出了一项关于双食双星系统V994 Her的独特五重系统的最新研究。 方法：基于新获得的光度观测数据，我们分析了V994 Her两个食双星周期的变化。 结果：我们发现这两个食双星围绕共同质心的轨道周期约为2.9年，而不是先前报道的6.3年。 此外，该系统现在似乎接近共面（i ~ 84°），我们还修正了所有四个食星个体的质量。两个食双星分别显示出约116年和111年的缓慢近日点进动。 A对B在天空中的距离约为17毫角秒，这对观测者来说是个好消息，因为未来几年内可能可以通过干涉测量法检测到。 结论：所有这些结果均基于V994 Her的光度观测及其两个食双星周期变化的详细分析。 显示英文摘要

摘要： Aims: We present a new updated study of the unique quintuple system of two eclipsing binaries, V994 Her. Methods: Based on new obtained photometric observations, we analysed the period variations of the two eclipsing pairs of V994 Her. Results: We found that the orbital period of the two eclipsing binaries around a common barycenter is about 2.9 yrs instead of the original period, which was reported as 6.3 yrs. Moreover, the system now seems to be close to coplanar (i ~ 84deg), and we also revised the individual masses of all four eclipsing components. The two eclipsing pairs show slow apsidal motion with periods of about 116 and 111 yrs, respectively. Pairs A and B are distant by about 17 mas on the sky, which is encouraging for observers because an interferometric detection may be possible in the next years. Conclusions: All of these results are based on the photometric observations of V994 Her and its detailed analysis of the period changes of the two eclipsing binaries.