The vertical metallicity gradients of mono-age stellar populations in the Milky Way with the RAVE and Gaia data
The vertical metallicity gradients of mono-age stellar populations in the Milky Way with the RAVE and Gaia data
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DOI：
10.1093/mnras/stx3285
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发表时间：
2017-06
影响因子：
4.8
通讯作者：
I. Ciucua;D. Kawata;Jane Lin;L. Casagrande;G. Seabroke;M. Cropper
中科院分区：
文献类型：
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作者：
I. Ciucua;D. Kawata;Jane Lin;L. Casagrande;G. Seabroke;M. Cropper
我们从交叉匹配的Tycho-Gaia天体测量解和径向速度实验(RAVE)第5版数据中选取了18435颗矮星，研究了0到11Gyr之间五个单年龄恒星群的垂直金属丰度梯度。我们发现垂直金属丰度梯度与年龄之间存在相关性，最年轻的恒星群没有垂直金属丰度梯度，而年长的恒星群的垂直金属丰度梯度越来越陡峭。圆盘平面上的金属丰度在2到8Gyr之间几乎保持不变，而对于8<；t≤11Gyr群体来说，它变得明显较低。目前的分析还表明，金属丰度的本征色散随着年龄的增长而稳步增加。我们讨论了我们的结果与(薄)盘星是由耀斑(薄)星形成盘形成的情况一致的。
We investigate the vertical metallicity gradients of five mono-age stellar populations between 0 and 11 Gyr for a sample of 18 435 dwarf stars selected from the cross-matched Tycho-Gaia Astrometric Solution and Radial Velocity Experiment (RAVE) Data Release 5. We find a correlation between the vertical metallicity gradients and age, with no vertical metallicity gradient in the youngest population and an increasingly steeper negative vertical metallicity gradient for the older stellar populations. The metallicity at disc plane remains almost constant between 2 and 8 Gyr, and it becomes significantly lower for the 8 < t ≤ 11 Gyr population. The current analysis also reveals that the intrinsic dispersion in metallicity increases steadily with age.We discuss that our results are consistent with a scenario that (thin) disc stars formed from a flaring (thin) star-forming disc.