C. Cabezas, M. Agúndez, C. Pérez, D. Villar-Castro, G. Molpeceres, D. Pérez, A. L. Steber, R. Fuentetaja, B. Tercero, N. Marcelino, A. Lesarri, P. de Vicente, and J. Cernicharo
reported on the
Discovery of Interstellar Phenalene (//c//-C<sub>13</sub>H<sub>10</sub>): A new Piece in the Chemical Puzzle of PAHs in Space
Astron. Astrophys. 701, Art. No. L8 (2025).
Phenalene was identified through several a-type rotational transitions, often series easier to detect because of oblate pairing of the transitions having the same Kc close to J and then blended with weaker b-type transitions having equivalent quantum numbres. Some isolated b-type transitions were also assigned in the astronomical spectrum. The identifications were based on the QUIJOTE molecular line survey carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz, but phenalene assignments were made only up to 39.8 GHz. A rotational temperature of 8 K was derived. The column density of phenalene appears to be slightly larger than that of the lighter indene, albeit with considerable uncertainty.
Contributor(s): H. S. P. Müller; 09, 2025