论文标题
au麦克风中H $ _2 $的神秘事件
The Mysterious Affair of the H$_2$ in AU Mic
论文作者
论文摘要
分子氢是银河系中最丰富的分子，并且在行星，它们的室外环境及其许多宿主星星中起着重要作用。我们已经在静止和耀斑期间使用HST-Stis的高分辨率FUV光谱在AU MIC系统中证实了分子氢。 Au Mic是$ \ sim $ 23 Myr m矮人，它拥有碎屑盘和至少两个行星。我们估计气体在1000至2000 K时的温度，与先前的检测一致。基于H $ _2 $线配置文件的径向速度和宽度以及H $ _2 $线对恒星耀斑的响应，H $ _2 $线排放可能是在恒星中产生的，而不是在磁盘或行星中产生。但是，这种气体的温度大大低于光球温度（$ \ sim $ 3650 K）和其星斑的预测温度（$ \ gtrsim $ 2650 K）。我们讨论了较冷的恒星斑点或较低序列的光球中较冷的层的可能性。
Molecular hydrogen is the most abundant molecule in the Galaxy and plays important roles for planets, their circumstellar environments, and many of their host stars. We have confirmed the presence of molecular hydrogen in the AU Mic system using high-resolution FUV spectra from HST-STIS during both quiescence and a flare. AU Mic is a $\sim$23 Myr M dwarf which hosts a debris disk and at least two planets. We estimate the temperature of the gas at 1000 to 2000 K, consistent with previous detections. Based on the radial velocities and widths of the H$_2$ line profiles and the response of the H$_2$ lines to a stellar flare, the H$_2$ line emission is likely produced in the star, rather than in the disk or the planet. However, the temperature of this gas is significantly below the temperature of the photosphere ($\sim$3650 K) and the predicted temperature of its star spots ($\gtrsim$2650 K). We discuss the possibility of colder star spots or a cold layer in the photosphere of a pre-main sequence M dwarf.
