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arXiv · 2304.01066

Discovery of two metallic cyanoacetylides in IRC+10216: HMgCCCN and NaCCCN

C. Cabezas·J. R. Pardo·M. Agundez·B. Tercero·N. Marcelino·Y. Endo·P. de Vicente·M. Guelin·J. Cernicharo
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Abstract

We report on the detection of a series of six lines in the ultra-deep Q-band integration toward IRC+10216 carried out with the Yebes 40m telescope, which are in harmonic relation with integer quantum numbers J from 12 to 18. After a detailed analysis of all possible carriers, guided by high-level quantum chemical calculations, we conclude that the lines belong to HMgCCCN, named hydromagnesium cyanoacetylide. The rotational temperature and column density derived for HMgCCCN are 17.1 +/- 2.8K and (3.0 +/- 0.6) e12 cm-2, respectively. The observed abundance ratio between MgCCCN and HMgCCCN is 3. In addition, we report the discovery in space, also toward IRC+10216, of sodium cyanoacetylide, NaCCCN, for which accurate laboratory data are available. For this species we derive a rotational temperature of 13.5 +/- 1.7K and a column density of (1.2 +/- 0.2) e11 cm-2.

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C. Cabezas, J. R. Pardo, M. Agundez, B. Tercero, N. Marcelino, Y. Endo, P. de Vicente, M. Guelin, J. Cernicharo. 2023-04-03. Discovery of two metallic cyanoacetylides in IRC+10216: HMgCCCN and NaCCCN. https://doi.org/10.1051/0004-6361/202346462

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