论文标题
VLBA对猎户座星云群中无线电星团的调查：I。非热无线电人口
A VLBA Survey of radio stars in the Orion Nebula Cluster: I. The nonthermal radio population
论文作者
论文摘要
我们提出了针对猎户座星云群（ONC）深入的VLA调查中的所有556个紧凑型无线电源的非热发射的四次VLBA调查的第一个结果。我们将VLBA识别为前所未有的123个来源的同行。其中41个没有X射线对应物，其中34个也没有显示近红外的对应物。由于这些无法通过外层次背景来源来解释，因此这表明了年轻恒星物体的ONC种群的组成部分，这些物体太深了，甚至无法检测到X射线。我们发现普遍存在的可变性，甚至在四个时期中只有一个中的大多数最高s/n来源都检测到。 VLA数据中的负光谱指数和极端变异性都不是VLBA检测的良好预测指标。
We present first results of a four-epoch VLBA survey for nonthermal emission toward all 556 compact radio sources previously identified in a deep VLA survey of the Orion Nebula Cluster (ONC). We identify VLBA counterparts toward an unprecedented 123 sources. Of these, 41 do not have X-ray counterparts, of which 34 also do not display near-infrared counterparts. Since these cannot be explained by extragalactic background sources, this suggests a component of the ONC population of young stellar objects that are too deeply embedded for even X-rays to be detectable. We find pervasive variability and detect even most of the highest-S/N sources in only one out of four epochs. Neither a negative spectral index nor extreme variability in the VLA data is a good predictor of a VLBA detection.
