Title :

Discovery of the acetyl cation, CH3CO+, in space and in the laboratory

Author(s) :

Cernicharo, J [Auteur]
Instituto de Física Fundamental [Madrid] [IFF]
Cabezas, C [Auteur]
Instituto de Física Fundamental [Madrid] [IFF]
National Chiao Tung University [NCTU]
Bailleux, S [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Margulès, L [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Physique Moléculaire aux Interfaces [PMI]
Motiyenko, R [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Zou, L [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Endo, Y [Auteur]
National Chiao Tung University [NCTU]
Bermúdez, C [Auteur]
Instituto de Física Fundamental [Madrid] [IFF]
National Chiao Tung University [NCTU]
Agúndez, M [Auteur]
Instituto de Física Fundamental [Madrid] [IFF]
National Chiao Tung University [NCTU]
Marcelino, N [Auteur]
Instituto de Física Fundamental [Madrid] [IFF]
National Chiao Tung University [NCTU]
Lefloch, B [Auteur]
Tercero, B [Auteur]
de Vicente, P [Auteur]

Journal title :

Astronomy and Astrophysics - A&A

Pages :

L7

Publisher :

EDP Sciences

Publication date :

2021-02

ISSN :

0004-6361

English keyword(s) :

astrochemistry -ISM
molecules -ISM
individual objects
TMC-1 -line
identification -molecular data

HAL domain(s) :

Planète et Univers [physics]/Astrophysique [astro-ph]/Astrophysique galactique [astro-ph.GA]

English abstract : [en]

Using the Yebes 40 m and IRAM 30 m radiotelescopes, we detected two series of harmonically related lines in space that can be fitted to a symmetric rotor. The lines have been seen towards the cold dense cores TMC-1, L483, ...
Show more >Using the Yebes 40 m and IRAM 30 m radiotelescopes, we detected two series of harmonically related lines in space that can be fitted to a symmetric rotor. The lines have been seen towards the cold dense cores TMC-1, L483, L1527, and L1544. High level of theory ab initio calculations indicate that the best possible candidate is the acetyl cation, CH 3 CO + , which is the most stable product resulting from the protonation of ketene. We have produced this species in the laboratory and observed its rotational transitions J u = 10 up to J u = 27. Hence, we report the discovery of CH 3 CO + in space based on our observations, theoretical calculations, and laboratory experiments. The derived rotational and distortion constants allow us to predict the spectrum of CH 3 CO + with high accuracy up to 500 GHz. We derive an abundance ratio N(H 2 CCO)/N(CH 3 CO +) ∼ 44. The high abundance of the protonated form of H 2 CCO is due to the high proton affinity of the neutral species. The other isomer, H 2 CCOH + , is found to be 178.9 kJ mol −1 above CH 3 CO +. The observed intensity ratio between the K = 0 and K = 1 lines, ∼2.2, strongly suggests that the A and E symmetry states have suffered interconversion processes due to collisions with H and/or H 2 , or during their formation through the reaction of H + 3 with H 2 CCO.Show less >

Language :

Anglais

Popular science :

Non

Collections :

• Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) - UMR 8523

Source :

Harvested from HAL