Show pageOld revisionsBacklinksBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ===== On the Detection of the HC2nN Radicals in Space ===== The cyanomethylene radical HCCN was observed with the IRAM 30 m telescope in the outer part of the circumstellar shell of the carbon-rich late-type star CW Leo, also known as IRC +10216, by\\ M. Guélin and J. Cernicharo,\\ **[[https://ui.adsabs.harvard.edu/abs/1991A%26A...244L..21G|Astronomical Detection of the HCCN Radical – Toward a New Family of Carbon-Chain Molecules ?]]**\\ //Astron. Astrophys.// **244**, L21–L24 (1991).\\ 9 fine structure components of 4 rotational transitions (//N// = 4 – 3 to 7 – 6) between 87 and 154 GHz were not or not significantly blended. A rotational temperature of 12±4 K was derived which was modified slightly to 15±2 K in the letter describing the detection of HC<sub>4</sub>N, see below.\\ Two features near 110 GHz detected toward Sgr B2 and Orion A are due to a minor velocity component of C<sup>18</sup>O and vibrationally excited HC<sub>3</sub>N, respectively. More recently, the detection of the next member, cyanoethynylmethylene, was also detected with the same instrument in the outer part of the circumstellar shell of CW Leo:\\ J. Cernicharo, M. Guélin, and J. R. Pardo,\\ **[[https://doi.org/10.1086/426439|Detection of the Linear Radical HC<sub>4</sub>N in IRC +10216]]**\\ //Astrophys. J.// **615**, L145–L148 (2004).\\ 12 fine structure components of 4 rotational transitions (//N// = 18 – 17 to 21 – 20) between 82 and 97 GHz were detected; 4 lines were partially blended. A rotational temperature of 25±4 K was derived, similar to that of HC<sub>3</sub>N in this source. ---- Contributor(s): H. S. P. Müller; 11, 2004; 01, 2012 ---- molecules/ism/hccn_etc.txt Last modified: 2019/10/22 16:39by mueller