The Star Formation History in the Solar Neighborhood as Told by Massive White Dwarfs
The Star Formation History in the Solar Neighborhood as Told by Massive White Dwarfs
复制标题
大质量白矮星讲述的太阳系附近的恒星形成历史
作者：
J. Isern
白色矮星（WD）是低质量和中等质量恒星的残余。由于电子的简并性，它们的演化只是一个简单的重力热冷却过程。最近，得益于盖亚数据，我们可以构建太阳附近（pc）大质量（）WD的光度函数。因为它们的祖先的寿命很短，父母和女儿的出生时间非常接近，这有利于重建（有效）星星形成率。这个速率在银河系早期从零开始增长，在6-7 Gyr前达到最大值。它下降了，250亿年前开始再次攀升，在2-3亿年前达到最大值;此后它一直在下降。有一些最近星星形成爆发的痕迹，但这里使用的方法不适合最近出生的WD。
White dwarfs (WDs) are the remnants of low- and intermediate-mass stars. Because of electron degeneracy, their evolution is just a simple gravothermal process of cooling. Recently, thanks to Gaia data, it has been possible to construct the luminosity function of massive ( ) WDs in the solar neighborhood ( pc). Because the lifetime of their progenitors is very short, the birth times of both parents and daughters are very close and facilitate the reconstruction of an (effective) star formation rate. This rate started growing from zero during the early Galaxy and reached a maximum 6–7 Gyr ago. It declined and ∼5 Gyr ago started to climb once more, reaching a maximum 2–3 Gyr ago; it has decreased since then. There are some traces of a recent star formation burst, but the method used here is not appropriate for recently born WDs.