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arXiv · 1905.08395

A SiO J = 5 - 4 Survey Toward Massive Star Formation Regions

Shanghuo Li·Junzhi Wang·Min Fang·Qizhou Zhang·Fei Li·Zhi-Yu Zhang·Juan Li·Qingfeng Zhu·Shaoshan Zeng
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Abstract

We performed a survey in the SiO $J=5\rightarrow4$ line toward a sample of 199 Galactic massive star-forming regions at different evolutionary stages with the SMT 10 m and CSO 10.4 m telescopes. The sample consists of 44 infrared dark clouds (IRDCs), 86 protostellar candidates, and 69 young \HII\ regions. We detected SiO $J=5\rightarrow4$ line emission in 102 sources, with a detection rate of 57\%, 37\%, and 65\% for IRDCs, protostellar candidates, and young \HII\ regions, respectively. We find both broad line with Full Widths at Zero Power (FWZP) $>$ 20 \kms and narrow line emissons of SiO in objects at various evolutionary stages, likely associated with high-velocity shocks and low-velocity shocks, respectively. The SiO luminosities do not show apparent differences among various evolutionary stages in our sample. We find no correlation between the SiO abundance and the luminosity-to-mass ratio, indicating that the SiO abundance does not vary significantly in regions at different evolutionary stages of star formation.

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Shanghuo Li, Junzhi Wang, Min Fang, Qizhou Zhang, Fei Li, Zhi-Yu Zhang, Juan Li, Qingfeng Zhu, Shaoshan Zeng. 2019-05-21. A SiO J = 5 - 4 Survey Toward Massive Star Formation Regions. https://doi.org/10.3847/1538-4357%2Fab1e4c

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