论文标题
GAIA0007-1605：一个旧的三重系统，内部棕色矮人矮人二进制和外部白矮人伴侣
Gaia0007-1605: an old triple system with an inner brown dwarf-white dwarf binary and an outer white dwarf companion
论文作者
论文摘要
我们将GAIA0007-1605AC识别为层次三重系统的第一个内部棕色矮人矮人二进制，其中外部分量是另一个白色矮人（GAIA0007-1605B）。 From optical/near-infrared spectroscopy obtained at the Very Large Telescope with the X-Shooter instrument and/or from Gaia photometry plus SED fitting, we determine the effective temperatures and masses of the two white dwarfs (12018+-68 K, 0.54+-0.01 Msun for Gaia0007-1605A and 4445+-116 K, 0.56+-0.05 Msun for GAIA0007-1605B）和棕色矮人的有效温度（1850+-50 K；对应于光谱型L3+-1）。通过分析GAIA0007-1605AC的可用苔丝光曲线，我们检测到一个1.0446+-0.0015天的信号，幅度为6.25 ppt，我们将其解释为棕色矮人表面上白矮胎的辐射效应的轨道周期。这促使我们推测过去的二进制在过去的一个共同的信封阶段演变。使用白色外部矮人作为cosmochronometer并分析系统的运动学特性，我们得出结论，三个系统大约是10 gyr。
We identify Gaia0007-1605AC as the first inner brown dwarf-white dwarf binary of a hierarchical triple system in which the outer component is another white dwarf (Gaia0007-1605B). From optical/near-infrared spectroscopy obtained at the Very Large Telescope with the X-Shooter instrument and/or from Gaia photometry plus SED fitting, we determine the effective temperatures and masses of the two white dwarfs (12018+-68 K, 0.54+-0.01 Msun for Gaia0007-1605A and 4445+-116 K, 0.56+-0.05 Msun for Gaia0007-1605B) and the effective temperature of the brown dwarf (1850+-50 K; corresponding to a spectral type L3+-1). By analysing the available TESS light curves of Gaia0007-1605AC we detect a signal at 1.0446+-0.0015 days with an amplitude of 6.25 ppt, which we interpret as the orbital period modulated from irradiation effects of the white dwarf on the brown dwarf's surface. This drives us to speculate that the inner binary evolved through a common envelope phase in the past. Using the outer white dwarf as a cosmochronometer and analysing the kinematic properties of the system, we conclude that the triple system is about 10 Gyr old.
