论文标题
恒星形成的全球视图：Glostar银河平面调查。 vi。无线电源目录II：$ 28^\ circ <\ ell <36^\ circ $和$ | b | <1^\ circ $，vla b-configuration
A global view on star formation: The GLOSTAR Galactic plane survey. VI. Radio Source Catalog II: $28^\circ < \ell < 36^\circ$ and $|b| < 1^\circ$, VLA B-configuration
论文作者
论文摘要
作为GLOSTAR调查的一部分，我们在其B构型中使用VLA观察了28d和36d的纵向之间的银河平面部分，以及在C频段（4--8 GHz）的-1d到 +1d的纬度。为了减少我们对（u，v）平面的覆盖范围无法很好地恢复的扩展来源的污染，我们丢弃了对在角度尺度上发射敏感的短基线$ <4“ $。产生的无线电连续图像具有1.0”的无线电连续性图像为1.0英寸，且灵敏度为$ \sim60μ$ Jy $ jy $ jy〜eb $ jy〜beb $ $ jy〜 $^$^ - 1}它是最敏感的无线电调查，涵盖了带有该角度分辨率的银河平面的大面积。使用自动源提取算法与视觉检查结合使用，以确定总共3325个无线电源。总共1457个无线电来源为$ \geq7σ$，包括我们高度可靠的目录；其中72个分组为22个碎片源，例如扩展和解决源的多个组件。为了探索我们在毫米和红外波长中搜索的分类无线电来源的性质。我们的分类尝试导致93个HII区域候选者，104个无线电星，64个行星星云，而大多数剩余的无线电来源被认为是外层状的来源。我们研究了被归类为HII区域候选者的无线电源的光谱指数（$α$，$s_ν\proptoν^α$），发现许多无线电源具有负值。这可能意味着这些无线电来源代表了年轻的恒星物体，这些物体是刺激HII地区的高质量恒星周围的明星簇的成员，但这些HII地区本身并不是。通过比较Glostar和Cornish调查的峰值通量密度，我们已经确定了49个可变的无线电源，其中大多数具有未知性质。此外，我们还提供了在5至7 $σ$水平内检测到的1866个无线电源的列表。
As part of the GLOSTAR survey we have used the VLA in its B-configuration to observe the part of the Galactic plane between longitudes of 28d and 36d and latitudes from -1d to +1d at the C-band (4--8 GHz). To reduce the contamination of extended sources that are not well recovered by our coverage of the (u, v)-plane we discarded short baselines that are sensitive to emission on angular scales $<4"$. The resulting radio continuum images have an angular resolution of 1.0", and sensitivity of $\sim60 μ$Jy~beam$^{-1}$; making it the most sensitive radio survey covering a large area of the Galactic plane with this angular resolution. An automatic source extraction algorithm was used in combination with visual inspection to identify a total of 3325 radio sources. A total of 1457 radio sources are $\geq7σ$ and comprise our highly reliable catalog; 72 of these are grouped as 22 fragmented sources, e.g., multiple components of an extended and resolved source. To explore the nature of the catalogued radio sources we searched for counterparts at millimeter and infrared wavelengths. Our classification attempts resulted in 93 HII region candidates, 104 radio stars, 64 planetary nebulae, while most of the remaining radio sources are suggested to be extragalactic sources. We investigated the spectral indices ($α$, $S_ν\proptoν^α$) of radio sources classified as HII region candidates and found that many have negative values. This may imply that these radio sources represent young stellar objects that are members of the star clusters around the high mass stars that excite the HII regions, but not these HII regions themselves. By comparing the peak flux densities from the GLOSTAR and CORNISH surveys we have identified 49 variable radio sources, most of them with an unknown nature. Additionally, we provide the list of 1866 radio sources detected within 5 to 7$σ$ levels.
