K. L. K. Lee, R. A. Loomis, A. M. Burkhardt, I. R. Cooke, C. Xue, M. A. Siebert, C. N. Shingledecker, A. Remijan, S. B. Charnley, M. C. McCarthy, and B. A. McGuire
reported on the
Discovery of Interstellar //trans//-Cyanovinylacetylene (HC≡CCH=CHC≡N) and Vinylcyanoacetylene (H₂C=CHC₃N) in GOTHAM Observations of TMC-1
Astrophys. J. Lett. 908, Art. No. L11 (2021).
The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the ¹⁴N hyperfine structure splitting. 2E-Penten-4-ynenitrile (here called trans-E-cyanovinylacetylene) and cyanoethynylethene (aka 4-penten-2-ynenitrile, here called vinylcyanoacetylene) were indentified through line-stacking with decent signal-to-noise ratios and very similar abundances. The significance of the cyanoethynylethene detections is somewhat on the edge (5.5σ). Two other isomers, 2Z-Penten-4-ynenitrile (here called trans-Z-cyanovinylacetylene) and 2-methylene-3-butynenitrile (here called cis-cyanovinylacetylene), were not identified.

Contributor(s): H. S. P. Müller; 02, 2021