Astronomers using the 40-m radio telescope at Yebes Observatory have detected two new complex molecules, butadiynethionyl (HCCCCS) and ethynylbutatrienyliden (HCCCHCCC), towards the Taurus Molecular Cloud 1.
Structure of the two molecules detected in TMC-1. Image credit: ESA / Herschel / NASA / JPL-Caltech / R. Hurt, JPL-Caltech / Fuentetaja et al. / Sci.News.
The Taurus Molecular Cloud 1 (TMC-1) is a starless cloud core located about 440 light-years away from Earth in the constellation of Taurus.
It is part of the Taurus Molecular Cloud and presents an interesting carbon-rich chemistry.
“The number of molecules discovered in the cold dark cloud TMC-1 — both with the Yebes-40 m radio telescope through the QUIJOTE1 line survey and the Green Bank 100-m radio telescope with the GOTHAM survey — demonstrates the great importance of this source for a complete understanding of the chemistry of the interstellar medium,” said Instituto de Física Fundamental astronomer Raúl Fuentetaja and colleagues.
“Chemical models are not yet accurate enough to predict all the molecules that have been discovered, so we must continue to study the various chemical reactions in order to better constrain models of cold pre-stellar cores.”
“The TMC-1 cloud is remarkably rich in hydrocarbons, such as long carbon chains, propargyl, vinyl acetylene, and allenyl diacetylene,” they added.
“Furthermore, several cyclic molecules, such as indene, cyclopentadiene, ortho-benzyne, and fulvenallene, have been discovered there.”
In their new study, Dr. Fuentetaja and co-authors observed the TMC-1 core in the radio frequency range of 31.1-50.2 GHz.
The observations were made as part of the ongoing QUIJOTE line survey, carried out with the Yebes 40-m telescope.
“We used a new receiver built within the Nanocosmos project, which consists of two cold high electron mobility transistor amplifiers covering the 31.0-50.3 GHz band with horizontal and vertical polarizations,” the astronomers explained.
“The data come from several observing runs carried out between December 2019 and May 2022, and correspond to 546 hours of observing time on source.”
The researchers were able to detect two new molecules, butadiynethionyl and ethynylbutatrienyliden, towards TMC-1.
One of these molecules, butadiynethionyl, is a sulfur-bearing species.
“We investigated the formation of these two molecules using chemical modeling calculations,” the authors said.
“The observed abundances can be accounted for by assuming standard gas-phase formation routes involving neutral-neutral reactions and ion-neutral reactions.”
The team’s paper was published in the journal Astronomy & Astrophysics.
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R. Fuentetaja et al. 2022. Discovery of two new interstellar molecules with QUIJOTE: HCCCHCCC and HCCCCS. A&A 667, L4; doi: 10.1051/0004-6361/202245018
Source link: https://www.sci.news/astronomy/interstellar-medium-organic-molecules-11370.html
