论文标题
S169的物理表征：与巨大的恒星形成区域IRAS12326-6245相关的典型IR气泡
Physical characterization of S169: A prototypical IR bubble associated with the massive star-forming region IRAS12326-6245
论文作者
论文摘要
为了研究银河IR气泡的特性及其在大规模恒星形成中的影响，我们介绍了IR气泡S169的研究，该研究与大型恒星形成区域IRAS12326-6245有关。我们使用了CO（2-1），$^{13} $ CO（2-1），C $^{18} $ O（2-1），HCN（3-2）和HCO+（3-2）线数据，该数据用Apex望远镜获得了研究Nebula和IRAS源的分子气体的特性。为了分析灰尘的特性和分布，我们使用了IRAC-Glimpse，Herschel和Atlasgal数据。使用从SUMSS调查和SuperCOSMOS数据库中获得的图像研究了离子气体的性能。在搜索该地区的恒星和原始物体时，我们使用了IR和光点源calalogs。新的最高观测使我们能够识别与星云相关的三个分子组件，即：$ - $ -39 km/s（零件A），$ 25 km/s/s（组件B）和$ -17 km/s/s/s（组件C）。在组分A中鉴定了六个分子冷凝（MC1至MC6），MC3（最密集，更大）是IRAS12326-6245的分子对应物。对于此来源，我们估计H $ _2 $列密度最高8 $ \ times $ 10 $^{23} $ cm $^{ - 2} $。为了解释组件A，B和C的形态和速度，我们提出了一个简单的模型，该模型由一个部分完整的半球状结构组成，该结构在〜12 km/s处扩展。该模型的引入导致了有关S169和IRAS12326-6245的距离的讨论，估计为〜2 kpc。确定了几个候选YSO，主要投影到分子凝结MC3，MC4和MC5上，这表明在星云的边界，恒星形成过程非常活跃。可观察到的参数和建模参数之间的比较不足以辨别收集和折叠机制是否在S169的边缘作用。
With the aim of studying the properties of Galactic IR bubbles and their impact in massive star formation, we present a study of the IR bubble S169, associated with the massive star forming region IRAS12326-6245. We used CO(2-1),$^{13}$CO(2-1), C$^{18}$O(2-1), HCN(3-2), and HCO+(3-2) line data obtained with the APEX telescope to study the properties of the molecular gas in the nebula and the IRAS source . To analyze the properties and distribution of the dust, we used IRAC-GLIMPSE, Herschel, and ATLASGAL data. The properties of the ionized gas were studied using images obtained from the SUMSS survey and SuperCOSMOS database. In our search for stellar and protostellar objects in the region, we used IR and optical point source calalogs. The new APEX observations allowed us to identify three molecular components associated with the nebula, namely: at $-$39 km/s (component A), $-$25 km/s (component B), and $-$17 km/s (component C). Six molecular condensations (MC1 to MC6) were identified in component A, with MC3 (the densest and more massive one) being the molecular counterpart of IRAS12326-6245. For this source, we estimated an H$_2$ column density up to 8$\times$10$^{23}$ cm$^{-2}$. To explain the morphology and velocity of components A, B, and C, we propose a simple model consisting of a partially complete semisphere-like structure expanding at ~ 12 km/s. The introduction of this model has led to a discussion about the distance to both S169 and IRAS12326-6245, which was estimated to be ~ 2 kpc. Several candidate YSOs were identified, projected mostly onto the molecular condensations MC3, MC4, and MC5, which indicates that the star-formation process is very active at the borders of the nebula. A comparison between observable and modeled parameters was not enough to discern whether the collect-and-collapse mechanism is acting at the edge of S169.
