论文标题
盖亚（Gaia）所说
Star formation history of the solar neighbourhood as told by Gaia
论文作者
论文摘要
GAIA DR2目录是当今可用的恒星天文和光度数据的最佳来源。银河系的历史在此数据集中用石头写成。视差和光度法告诉我们今天的恒星在哪里，它们的形成何时以及化学含量，即它们的恒星形成历史（SFH）。我们开发了一个适合重建已解决恒星人群的SFH的贝叶斯分层模型。我们研究了恒星在盖亚DR2中100 pc内的恒星比$ g \，= \，15 $更明亮，并根据先前的确定而得出了太阳邻域的SFH，并且由于检测到化学富集而对它们进行了改进。我们的结果表明，大约10 Gyr的最大恒星形成活性，产生大量恒星，略低于太阳金属性（Z = 0.014），然后降低恒星形成的最低水平降至8 Gyr左右。安静的时期后，恒星形成在大约5 Gyr以前的最大值上升到最大值，形成了太阳金属性的星星（Z = 0.017）。最后，恒星的形成一直在减少，直到当前为止，在残留水平下形成Z = 0.03的恒星。我们通过忽略样品中未解决的二进制恒星的存在来测试推断的SFH中引入的效果，从而减少了明显的限制幅度，并修改了恒星的初始质量函数。
The Gaia DR2 catalog is the best source of stellar astrometric and photometric data available today. The history of the Milky Way galaxy is written in stone in this data set. Parallaxes and photometry tell us where the stars are today, when were they formed, and with what chemical content, i.e. their star formation history (SFH). We develop a Bayesian hierarchical model suited to reconstruct the SFH of a resolved stellar population. We study the stars brighter than $G\,=\,15$ within 100 pc of the Sun in Gaia DR2 and derive a SFH of the solar neighbourhood in agreement with previous determinations and improving upon them because we detect chemical enrichment. Our results show a maximum of star formation activity about 10 Gyr ago, producing large numbers of stars with slightly below solar metallicity (Z=0.014), followed by a decrease in star formation up to a minimum level occurring around 8 Gyr ago. After a quiet period, star formation rises to a maximum at about 5 Gyr ago, forming stars of solar metallicity (Z=0.017). Finally, star formation has been decreasing until the present, forming stars of Z=0.03 at a residual level. We test the effects introduced in the inferred SFH by ignoring the presence of unresolved binary stars in the sample, reducing the apparent limiting magnitude, and modifying the stellar initial mass function.
