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arXiv · 1310.4801

Multi-wavelength study of triggered star formation around 25 H II regions

Jin-Long Xu·Jun-Jie Wang·Chang-Chun Ning·Chuan-peng Zhang
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Abstract

We have investigated 25 H II regions with bubble morphology in 13CO(1-0) and infrared data, to search the quantitative evidence for the triggering star formation by collect and collapse (CC) and radiatively driven implosion (RDI) models. These H II regions display the morphology of the complete or partial bubble at 8 um, which all are associated with the surrounding molecular clouds. We obtained that the electron temperature ranges from 5627 K to 6839 K in these H II regions, and the averaged electron temperature is 6083 K. The age of these H II regions is from 3.0\times10^{5} yr to 1.7\times10^{6} yr, and the mean age is 7.7\times10^{5} yr. Based on the morphology of the associated molecular clouds, we divided these H II regions into three groups, which may support CC and RDI models. We selected 23 young IRAS sources with the infrared luminosity of >10^{3}L_{\odot} in 19 H II regions. In addition, we identified some young stellar objects (including Class I sources), which are concentrated only in H II regions G29.007+0.076, G44.339-0.827, and G47.028+0.232. The polycyclic aromatic hydrocarbons (PAHs) emission of the three H II regions all show the cometary globule. Comparing the age of each H II region with the characteristic timescales for star formation, we suggest that the three H II regions can trigger the clustered star formation by RDI process. In addition, we for the first time detected seven molecular outflows in the five H II regions. These outflow sources may be triggered by the corresponding H II regions.

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Jin-Long Xu, Jun-Jie Wang, Chang-Chun Ning, Chuan-peng Zhang. 2013-10-16. Multi-wavelength study of triggered star formation around 25 H II regions. https://doi.org/10.1088/1674-4527/14/1/004

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