RT info:eu-repo/semantics/article
T1 Discovery of the Elusive Carbonic Acid (HOCOOH) in Space
A1 Sanz Novo, Miguel
A1 Rivilla, Víctor M.
A1 Jiménez Serra, Izaskun
A1 Martín Pintado, Jesús
A1 Colzi, Laura
A1 Zeng, Shaoshan
A1 Megías, Andrés
A1 López Gallifa, Álvaro
A1 Martínez Henares, Antonio
A1 Massalkhi, Sarah
A1 Tercero, Belén
A1 Vicente, Pablo de
A1 Martín, Sergio
A1 Andrés, David San
A1 Requena Torres, Miguel A.
K1 Ácido carbónico (HOCOOH)
K1 Carbonic acid (HOCOOH)
K1 Interstellar molecule
K1 Molécula interestelar
K1 21 Astronomía y Astrofísica
AB A quarter century after the detection of the last interstellar carboxylic acid, acetic acid (CH3COOH), we report the discovery of a new one, the cis-trans form of carbonic acid (HOCOOH), toward the Galactic center molecular cloud G+0.693–0.027. HOCOOH stands as the first interstellar molecule containing three oxygen atoms and the third carboxylic acid detected so far in the interstellar medium. Albeit the limited available laboratory measurements (up to 65 GHz), we have also directly identified several pairs of unblended lines in the astronomical data (between 75 and 120 GHz), which allowed us to slightly improve the set of spectroscopic constants. We derive a column density for cis-trans HOCOOH of N = (6.4 ± 0.4) × 1012 cm−2, which yields an abundance with respect to molecular H2 of 4.7 × 10−11. Meanwhile, the extremely low dipole moment (about 15 times lower) of the lower-energy conformer, cis-cis HOCOOH, precludes its detection. We obtain an upper limit to its abundance with respect to H2 of ≤1.2 × 10−9, which suggests that cis-cis HOCOOH might be fairly abundant in interstellar space, although it is nearly undetectable by radio astronomical observations. We derive a cis-cis/cis-trans ratio of ≤25, consistent with the smaller energy difference between both conformers compared with the relative stability of trans- and cis-formic acid. Finally, we compare the abundance of these acids in different astronomical environments, further suggesting a relationship between the chemical content found in the interstellar medium and the chemical composition of the minor bodies of the solar system, which could be inherited during the star formation process.
PB IOP Publishing
SN 0004-637X
YR 2023
FD 2023
LK https://uvadoc.uva.es/handle/10324/61053
UL https://uvadoc.uva.es/handle/10324/61053
LA eng
NO The Astrophysical Journal, 2023, Volume 954, Number 1
NO Producción Científica
DS UVaDOC
RD 27-dic-2024