===== On the Discovery of Ethenylidenecyclopentadiene in the ISM =====

J. Cernicharo, R. Fuentetaja, M. Agúndez, R. I. Kaiser, C. Cabezas, N. Marcelino, B. Tercero, J. R. Pardo, and P. de Vicente\\
reported on the\\
**[[https://doi.org/10.1051/0004-6361/202244399|Discovery of fulvenallene in TMC-1 with the QUIJOTE line survey]]**\\
//Astron. Astrophys.// **663**, Art. No. L9 (2022).\\
The molecular line survey was carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. Ethenylidenecyclopentadiene, aka fulvenallene, was detected in several //a//-type transitions having 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 3. A considerable fraction of the lines is not or only slightly blended. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived through a rotation diagram. Its column density is only about a factor of 4.5 lower than that of cyclopentadiene and about a factor of 11 to 26 of what has been estimated for ethene.\\
\\

----

Contributor(s): H. S. P. Müller; 08, 2022

----