论文标题
年轻的120兆格附近的双鱼座 - 厄立达斯恒星流的化学性质，流过银河系
The Chemical Nature of the Young 120-Myr-old Nearby Pisces-Eridanus Stellar Stream Flowing through the Galactic Disk
论文作者
论文摘要
最近，使用Gaia Mission启用的运动学数据，发现了一个新的圆柱形恒星恒星恒星藏在银河系磁盘中。最初认为这片被称为Pisces-Eridanus（PSC-ERI）的恒星流被认为与1 Gyr一样古老，但其恒星共享了与120myrs的种群一致的旋转时期分布。在这里，我们探讨了该恒星流的详细化学性质。我们使用麦当劳天文台对42颗PSC-ERI恒星进行了高分辨率光谱随访，并将这些数据与与低分辨率Lamost光谱调查一起观察到的40个成员的信息结合在一起。这些数据共同使我们能够测量光/奇数（li，na，al，sc，v），$α$（mg，si，ca，ti），fe-peak（CR，MN，MN，FE，CO，NI，ZN）和Neutron Capture（SR，Y，Y，Y，Y，BA，BA，la，nd，nd，eu）Elements沿Pssc-pssc-serie elemenie。我们发现，[Fe/H] = -0.03〜DEX和（2）在太阳金属度附近的流为（1），金属度扩展为0.07〜DEX（或排除异常值时0.04 DEX）。我们还发现（3）Li的丰度表明PSC-ERI为$ \ sim $ 120 Myr Old，符合其陀螺仪年龄。此外，PSC-ERI具有（4）[x/fe]丰度扩展，大多数元素中的不确定性大于典型的不确定性，（5）它是一个类似圆柱形的系统，其外边缘在中心周围旋转，并且（6）沿其主要轴的显着丰度梯度无明显的丰度梯度，除了[si/fe]的潜在弱梯度。这些结果表明，PSC-ERI是一个独特，年轻，化学有趣的实验室，用于测试我们对恒星和行星形成的理解。
Recently, a new cylindrical-shaped stream of stars up to 700 pc long was discovered hiding in the Galactic disk using kinematic data enabled by the Gaia mission. This stream of stars, dubbed Pisces-Eridanus (Psc-Eri), was initially thought to be as old as 1 Gyr, yet its stars shared a rotation period distribution consistent with a population that was 120-Myr-old. Here, we explore the detailed chemical nature of this stellar stream. We carried out high-resolution spectroscopic follow-up of 42 Psc-Eri stars using McDonald Observatory, and combined these data with information for 40 members observed with the low-resolution LAMOST spectroscopic survey. Together, these data enabled us to measure the abundance distribution of light/odd-Z (Li, Na, Al, Sc, V), $α$ (Mg, Si, Ca, Ti), Fe-peak (Cr, Mn, Fe, Co, Ni, Zn), and neutron capture (Sr, Y, Zr, Ba, La, Nd, Eu) elements along the Psc-Eri stream. We find that the stream is (1) near solar metallicity with [Fe/H] = -0.03~dex and (2) has a metallicity spread of 0.07~dex (or 0.04 dex when outliers are excluded). We also find that (3) the abundance of Li indicates that Psc-Eri is $\sim$120 Myr old, consistent with its gyrochronology age. Additionally, Psc-Eri has (4) [X/Fe] abundance spreads which are just larger than the typical uncertainty in most elements, (5) it is a cylindrical-like system whose outer edges rotate about the center and, (6) no significant abundance gradients along its major axis except a potentially weak gradient in [Si/Fe]. These results show that Psc-Eri is a uniquely close, young, chemically interesting laboratory for testing our understanding of star and planet formation.
