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arXiv · 1712.02206

A spectral line survey of IRC +10216 between 13.3 and 18.5 GHz

Xiao-Yan Zhang·Qing-Feng Zhu·Juan Li·Xi Chen·Jun-Zhi Wang·Jiang-Shui Zhang
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Abstract

A spectral line survey of IRC +10216 between 13.3 and 18.5 GHz is carried out using the Shanghai Tian Ma 65 m Radio Telescope (TMRT-65m) with a sensitivity of < 7 mK. Thirty-five spectral lines of 12 different molecules and radicals are detected in total. Except for SiS, the detected molecules are all carbon-chain molecules, including HC3N, HC5N, HC7N, HC9N, C6H, C6H-, C8H, SiC2, SiC4, c-C3H2 and l-C5H. The presence of rich carbon-bearing molecules is consistent with the identity of IRC +10216 as a carbon-rich AGB star. The excitation temperatures and column densities of the observed species are derived by assuming a local thermodynamic equilibrium and homogeneous conditions.

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Xiao-Yan Zhang, Qing-Feng Zhu, Juan Li, Xi Chen, Jun-Zhi Wang, Jiang-Shui Zhang. 2017-12-06. A spectral line survey of IRC +10216 between 13.3 and 18.5 GHz. https://doi.org/10.1051/0004-6361/201730791

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