论文标题
$Δμ$ star gj 3346的新白矮人伴侣
A new white dwarf companion to the $Δμ$ star GJ 3346
论文作者
论文摘要
我们向GJ3346的3.6英寸（$π\ sim $ 42 mas）K发现了一个白色矮人的伴侣，与Sphere@vlt观察到了与Gaia Dr1和TyCho-2这样的Secure system system secure consement and Speciess and sper@vlt观察到的一部分。白矮人，由于后者的固有微弱性，很难检测到它们是直接成像搜索的常见污染物。 GJ3346B的物理特性，例如其有效温度（11 $ \ times $^3 \ pm $ 500 k）以及系统的冷却年龄（648 $ \ pm $ 58，这使我们能够更好地理解系统历史记录。归类为年轻，实际上最有可能年龄在4个回旋中，因为质量（0.58 $ \ pm $ 0.01 $ m _ {\ odot} $）和gj3346b的分离（85 au）与观察到的$Δ$相吻合，这是一种进一步的确认。微弱的子赛车同伴。
We present the discovery of a white dwarf companion at 3.6" from GJ3346, a nearby ($π\sim$42 mas) K star observed with SPHERE@VLT as part of an open time survey for faint companions to objects with significant proper motion discrepancies ($Δμ$) between Gaia DR1 and Tycho-2. Syrius-like systems like GJ3346AB, which include a main sequence star and a white dwarf, can be difficult to detect because of the intrinsic faintness of the latter. They have, however, been found to be common contaminants for direct imaging searches. White dwarfs have in fact similar brightness to sub-stellar companions in the infrared, while being much brighter in the visible bands like those used by Gaia. Combining our observations with Gaia DR2 and with several additional archival data sets, we were able to fully constrain the physical properties of GJ3346B, such as its effective temperature (11$\times$10$^3\pm$500 K) as well as the cooling age of the system (648$\pm$58 Myrs). This allowed us to better understand the system history and to partially explains the discrepancies previously noted in the age indicators for this objects. Although further investigation is still needed, it seems that GJ3346, which was previously classified as young, is in fact most likely to be older than 4 Gyrs. Finally, given that the mass (0.58$\pm$0.01$M_{\odot}$)} and separation (85 au) of GJ3346B are compatible with the observed $Δμ$, this discovery represents a further confirmation of the potential of this kind of dynamical signatures as selection methods for direct imaging surveys targeting faint, sub-stellar companions.
