Millimetre-wave laboratory study of glycinamide and a search for it with ALMA towards Sagittarius B2(N)

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F22%3A43923972" target="_blank" >RIV/60461373:22340/22:43923972 - isvavai.cz</a>

Result on the web

<a href="https://www.aanda.org/articles/aa/full_html/2022/01/aa42350-21/aa42350-21.html" target="_blank" >https://www.aanda.org/articles/aa/full_html/2022/01/aa42350-21/aa42350-21.html</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202142350" target="_blank" >10.1051/0004-6361/202142350</a>

Result language

angličtina

Original language name

Millimetre-wave laboratory study of glycinamide and a search for it with ALMA towards Sagittarius B2(N)

Original language description

Context. Glycinamide (NH2CH2C(O)NH2) is considered to be one of the possible precursors of the simplest amino acid, glycine. Its only rotational spectrum reported so far has been in the centimetre-wave region on a laser-ablation generated supersonic expansion sample.Aims. The aim of this work is to extend the laboratory spectrum of glycinamide to the millimetre (mm) wave region to support searches for this molecule in the interstellar medium and to perform the first check for its presence in the high-mass star forming region Sagittarius B2(N).Methods. Glycinamide was synthesised chemically and was studied with broadband rotational spectroscopy in the 90-329 GHz region with the sample in slow flow at 50 degrees C. Tunnelling across a low-energy barrier between two symmetry equivalent configurations of the molecule resulted in splitting of each vibrational state and many perturbations in associated rotational energy levels, requiring careful coupled state fits for each vibrational doublet. We searched for emission of glycinamide in the imaging spectral line survey ReMoCA performed with the Atacama Large Millimetre/submillimetre Array towards Sgr B2(N). The astronomical spectra were analysed under the assumption of local thermodynamic equilibrium.Results. We report the first analysis of the mm-wave rotational spectrum of glycinamide, resulting in fitting - to experimental measurement accuracy - of over 1200 assigned and measured transition frequencies for the ground-state tunnelling doublet and of many lines for tunnelling doublets for two singly excited vibrational states. We also determine the precise vibrational separation in each doublet. We did not detect emission from glycinamide in the hot molecular core Sgr B2(N1S). We derived a column density upper limit of 1.5 x 10(16) cm(-2), which implies that glycinamide is at least seven times less abundant than aminoacetonitrile and 1.8 times less abundant than urea in this source. A comparison with results of astrochemical kinetics models for species related to glycinamide suggests that its abundance may be at least one order of magnitude below the upper limit obtained towards Sgr B2(N1S). This means that glycinamide emission in this source likely lies well below the spectral confusion limit in the frequency range covered by the ReMoCA survey.Conclusions. Thanks to the spectroscopic data provided by this study, the search for glycinamide in the interstellar medium can continue on a firm basis. Targetting sources with a lower level of spectral confusion, such as the Galactic Center shocked region G+0.693-0.027, may be a promising avenue.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10403 - Physical chemistry

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

ASTRONOMY &amp; ASTROPHYSICS

ISSN

0004-6361

e-ISSN

1432-0746

Volume of the periodical

657

Issue of the periodical within the volume

JAN 19 2022

Country of publishing house

FR - FRANCE

Number of pages

22

Pages from-to

"A99"

UT code for WoS article

000744244200012

EID of the result in the Scopus database

2-s2.0-85123379238