===== Detection of Circumstellar Cyanomethylidyne, C2N =====

J. K. Anderson and L. M. Ziurys,\\
reported on the\\
**[[https://doi.org/10.1088/2041-8205/795/1/L1|Detection of CCN (//X// <sup>2</sup>Π<sub>r</sub>) in IRC+10216: Constraining Carbon-chain Chemistry]]**,\\
//Astrophys. J.// **795** Art. No. L1 (2014).\\
The ARO 12 m and the ARO SMT were used to detect the two Λ-doubling components each of three rotational transitions in the <sup>2</sup>Π<sub>1/2</sub> lower energy spin ladder: the //J// = 9.5 – 8.5, 6.5 – 5.5, and the 4.5 – 3.5 transitions near 224.45, 153.63, and 106.36 GHz in the circumstellar envelope of CW Leonis. According to the authors, the higher frequency //f//-components are always unblended, whereas the //e//-components are always partially blended. Because of its rather low abundance, ratios of about 500 : 1 : 50 were derived for CN, C<sub>2</sub>N, and C<sub>3</sub>N, and its small dipole moment, the molecule was very hard to detect.


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Contributor(s): H. S. P. Müller; 10, 2014

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