论文标题
庞大的金属恒星形成区域NGC 346中嵌入式质体的近红外光谱
Near-infrared spectroscopy of embedded protostars in the massive metal-poor star-forming region NGC 346
论文作者
论文摘要
我们提出了中分辨率（r $ \ sim $ 4000）yj，nGC〜346中的候选年轻恒星对象（YSO）的H \＆k带光谱，这是金属贫困中最活跃的星形形成区域（z = 1/5 z $ _ $ _ {\ sun} $）小麦芽岩云。使用非常大的望远镜上的KMO（k波段多对象光谱仪）积分仪器获得光谱。从我们先前从MID-IR光度法和辐射转移模型鉴定出的18个候选高质量YSO的初始样本中，将大约一半通过我们的整体场数据分解为多个组件。我们总共检测到30个连续源，并为其中12个对象提取可靠的光谱。这些光谱显示了各种特征，包括氢重组线以及H $ _2 $，He〜 {\ sc I}和[Fe〜 {\ sc II}]的线，它们表示积聚，圆盘和大量YSO中流出的材料。我们从光谱上证实了九名YSO候选人的年轻性质，并将另外两个候选人视为OB明星。所有确认的YSO都具有BR $γ$的排放，但是尽管光谱中存在其他圆盘示踪剂，但从CO带头也没有看到发射。他\，{\ sc i} 〜1.083 $ $ m $ m的排放率也比银河系高得多。
We present medium-resolution (R $\sim$ 4000) YJ, H \& K band spectroscopy of candidate young stellar objects (YSOs) in NGC~346, the most active star-formation region in the metal-poor (Z = 1/5 Z$_{\sun}$) Small Magellanic Cloud. The spectra were obtained with the KMOS (K-Band Multi Object Spectrograph) integral field instrument on the Very Large Telescope. From our initial sample of 18 candidate high-mass YSOs previously identified from mid-IR photometry and radiative transfer model fits to their spectral energy distributions, approximately half were resolved into multiple components by our integral-field data. In total, we detect 30 continuum sources and extract reliable spectra for 12 of these objects. The spectra show various features including hydrogen recombination lines, and lines from H$_2$, He~{\sc i} and [Fe~{\sc ii}], which are indicative of accretion, discs and outflowing material in massive YSOs. We spectroscopically confirm the youthful nature of nine YSO candidates and identify two others as OB stars. All of the confirmed YSOs have Br$γ$ in emission, but no emission is seen from the CO bandhead, despite other disc tracers present in the spectra. He\,{\sc i}~1.083 $μ$m emission is also detected at appreciably higher rates than for the Galaxy.
