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Discovery of HC3O+ in space: The chemistry of O-bearing species in TMC-1.

ABSTRACT: Using the Yebes 40m and IRAM 30m radio telescopes, we detected a series of harmonically related lines with a rotational constant B 0=4460.590±0.001 MHz and a distortion constant D 0=0.511 ±0.005 kHz towards the cold dense core TMC-1. High-level-of-theory ab initio calculations indicate that the best possible candidate is protonated tricarbon monoxide, HC3O+. We have succeeded in producing this species in the laboratory and observed its J u -J l = 2-1 and 3-2 rotational transitions. Hence, we report the discovery of HC3O+ in space based on our observations, theoretical calculations, and laboratory experiments. We derive an abundance ratio N(C3O)/N(HC3O+)~7. The high abundance of the protonated form of C3O is due to the high proton affinity of the neutral species. The chemistry of O-bearing species is modelled, and predictions are compared to the derived abundances from our data for the most prominent O-bearing species in TMC-1.

SUBMITTER: Cernicharo J

PROVIDER: S-EPMC7116414 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Discovery of HC3O+ in space: The chemistry of O-bearing species in TMC-1.

Cernicharo J J Marcelino N N Agúndez M M Endo Y Y Cabezas C C Bermúdez C C Tercero B B de Vicente P P

Astronomy and astrophysics 20201023

Using the Yebes 40m and IRAM 30m radio telescopes, we detected a series of harmonically related lines with a rotational constant B 0=4460.590±0.001 MHz and a distortion constant D 0=0.511 ±0.005 kHz towards the cold dense core TMC-1. High-level-of-theory ab initio calculations indicate that the best possible candidate is protonated tricarbon monoxide, HC3O+. We have succeeded in producing this species in the laboratory and observed ...[more]

PMID: 33239825

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