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arXiv · 2103.06754

A search for cloud cores affected by shocked carbon chain chemistry in L1251

Xunchuan Liu·Y. Wu·C. Zhang·X. Chen·L. -H. Lin·S. -L. Qin·T. Liu·C. Henkel·J. Wang·H. -L. Liu·J. Yuan·L. -X. Yuan·J. Li·Z. -Q. Shen·D. Li·J. Esimbek·K. Wang·L. -X. Li·Kee-Tae Kim·L. Zhu·D. Madones·N. Inostroza·F. -Y. Meng·Tianwei Zhang·K. Tatematsu·Y. Xu·B. -G. Ju·A. Kraus·F. -W. Xu
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Abstract

We searched for shocked carbon chain chemistry (SCCC) sources with C$_3$S abundances surpassing those of HC$_5$N towards the dark cloud L1251, using the Effelsberg telescope at K-band (18 -- 26\,GHz). L1251-1 and L1251-3 are identified as the most promising SCCC sources. The two sources harbor young stellar objects. We conducted mapping observations towards L1251-A, the western tail of L1251, at $λ$ $\sim$3\,mm with the PMO 13.7 m and the NRO 45 m telescopes in lines of C$_2$H, N$_2$H$^+$, CS, HCO$^+$, SO, HC$_3$N and C$^{18}$O as well as in CO 3--2 using the JCMT. The spectral data were combined with archival data including Spitzer and Herschel continuum maps for further analysis. Filamentary sub-structures labeled as F1 to F6 were extracted in L1251, with F1 being associated with L1251-A hosting L1251-1. The peak positions of dense gas traced by HCO$^+$ are misaligned relative to those of the dust clumps. Episodic outflows are common in this region. The twisted morphology of F1 and velocity distribution along L1251-A may originate from stellar feedback. SCCC in L1251-1 may have been caused by outflow activities originated from the infrared source IRS1. The signposts of ongoing SCCC and the broadened line widths of C$_3$S and C$_4$H in L1251-1 as well as the distribution of HC$_3$N are also related to outflow activities in this region. L1251-1 (IRS1) together with the previously identified SCCC source IRS3 demonstrate that L1251-A is an excellent region to study shocked carbon chain chemistry.

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Xunchuan Liu, Y. Wu, C. Zhang, X. Chen, L. -H. Lin, S. -L. Qin, T. Liu, C. Henkel, J. Wang, H. -L. Liu, J. Yuan, L. -X. Yuan, J. Li, Z. -Q. Shen, D. Li, J. Esimbek, K. Wang, L. -X. Li, Kee-Tae Kim, L. Zhu, D. Madones, N. Inostroza, F. -Y. Meng, Tianwei Zhang, K. Tatematsu, Y. Xu, B. -G. Ju, A. Kraus, F. -W. Xu. 2021-03-11. A search for cloud cores affected by shocked carbon chain chemistry in L1251. https://doi.org/10.3847/1538-4357%2Fabee73

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