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arXiv · 1905.10322

Carbon-Chain Molecules in Molecular Outflows and Lupus I Region--New Producing Region and New Forming Mechanism

Yuefang Wu·Xunchuan Liu·Xi Chen·Lianghao Lin·Jinghua Yuan·Chao Zhang·Tie Liu·Zhiqiang Shen·Juan Li·Junzhi Wang·Sheng-Li Qin·Kee-Tae Kim·Hongli Liu·Lei Zhu·Diego Madones·Natalia Inostroza·C. Henkel·Tianwei Zhang·Di Li·Jarken Esimbek·Qinghui Liu
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Abstract

Using the new equipment of the Shanghai Tian Ma Radio Telescope, we have searched for carbon-chain molecules (CCMs) towards five outflow sources and six Lupus I starless dust cores, including one region known to be characterized by warm carbon-chain chemistry (WCCC), Lupus I-1 (IRAS 15398-3359), and one TMC-1 like cloud, Lupus I-6 (Lupus-1A). Lines of HC3N J=2-1, HC5N J=6-5, HC7N J=14-13, 15-14, 16-15 and C3S J=3-2 were detected in all the targets except in the outflow source L1660 and the starless dust core Lupus I-3/4. The column densities of nitrogen-bearing species range from 10$^{12}$ to 10$^{14}$ cm$^{-2}$ and those of C$_3$S are about 10$^{12}$ cm$^{-2}$. Two outflow sources, I20582+7724 and L1221, could be identified as new carbon-chain--producing regions. Four of the Lupus I dust cores are newly identified as early quiescent and dark carbon-chain--producing regions similar to Lup I-6, which together with the WCCC source, Lup I-1, indicate that carbon-chain-producing regions are popular in Lupus I which can be regard as a Taurus like molecular cloud complex in our Galaxy. The column densities of C3S are larger than those of HC7N in the three outflow sources I20582, L1221 and L1251A. Shocked carbon-chain chemistry (SCCC) is proposed to explain the abnormal high abundances of C3S compared with those of nitrogen-bearing CCMs. Gas-grain chemical models support the idea that shocks can fuel the environment of those sources with enough $S^+$ thus driving the generation of S-bearing CCMs.

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Yuefang Wu, Xunchuan Liu, Xi Chen, Lianghao Lin, Jinghua Yuan, Chao Zhang, Tie Liu, Zhiqiang Shen, Juan Li, Junzhi Wang, Sheng-Li Qin, Kee-Tae Kim, Hongli Liu, Lei Zhu, Diego Madones, Natalia Inostroza, C. Henkel, Tianwei Zhang, Di Li, Jarken Esimbek, Qinghui Liu. 2019-05-24. Carbon-Chain Molecules in Molecular Outflows and Lupus I Region--New Producing Region and New Forming Mechanism. https://doi.org/10.1093/mnras/stz1498

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