论文标题
来自盖亚DR2的白矮人同伴的精确年龄
Precise Ages of Field Stars From White Dwarf Companions in Gaia DR2
论文作者
论文摘要
我们分析了4 \，050宽的二进制星系，涉及白矮人（WD），通常是主序列（MS）星，该系统从\ citet [] [] [] [以下简称，T20] {Tian_2020}组装的大样品中绘制。使用建模代码base-9，我们确定系统的年龄，WD祖细胞的ZAMS质量，消光值（$ a_v $）和距离模量。丢弃年龄融合较差的案例，我们获得了3 \，551 WDS的年龄，中位年龄精度为$σ_τ/τ= 20 $ \％，并且系统年龄通常在1-6 Gyr的范围内。我们通过少数已知的簇以及通过236个WD-WD二进制文件进行了验证这些年龄。在假设组件是二进制系统中的共同评估的假设下，这对通常的低质量MS伴侣提供了精确的年龄约束，大多数其他任何其他方式都无法访问。
We analyze 4\,050 wide binary star systems involving a white dwarf (WD) and usually a main sequence (MS) star, drawn from the large sample assembled by \citet[][hereafter, T20]{Tian_2020}. Using the modeling code BASE-9, we determine the system's ages, the WD progenitors' ZAMS masses, the extinction values ($A_V$), and the distance moduli. Discarding the cases with poor age convergences, we obtain ages for 3\,551 WDs, with a median age precision of $σ_τ/τ= 20$\%, and system ages typically in the range of 1-6 Gyr. We validated these ages against the very few known clusters and through cross-validation of 236 WD-WD binaries. Under the assumption that the components are co-eval in a binary system, this provides precise age constraints on the usually low-mass MS companions, mostly inaccessible by any other means.
