Isocyanic acid (HNCO) in the hot molecular core G331.512-0.103: observations and chemical modelling

The authors thank the anonymous referee for the useful comments that improved the article. CMC acknowledges the support of CNPq, Conselho Nacional de Desenvolvimento Cientifico e Tecnologico Brazil, process number 141714/2016-6. This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - Brasil (CAPES) - Finance Code 001. LB acknowledges support fromCONICYT (Comision Nacional de Investigacion Cientifica y Tecnologica) project Basal AFB-170002. EM acknowledges support from the Brazilian agencies FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, grant 2014/22095-6) and CNPq (grant 150465/2019-0). MC acknowledges the financial support from theEuropean Union'sHorizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no 872081; from the Spanish National Research, Development, and Innovation plan (RDI plan) under the project PID2019-104002GB-C21; the Consejeria de Conocimiento, Investigacion y Universidad, Junta de Andalucia and European Regional Development Fund (ERDF), ref. SOMM17/6105/UGR; the Ministerio de Ciencia, Innovacion y Universidades (ref. COOPB20364); and by the Centro de Estudios Avanzados en Fisica, Matematicas y Computacion (CEAFMC) of the University of Huelva.Isocyanic acid (HNCO) is a simple molecule with a potential to form prebiotic and complex organic species. Using a spectral survey collected with the Atacama Pathfinder EXperiment, in this work we report the detection of 42 transitions of HNCO in the hot molecular core/outflow G331.512-0.103 (hereafter G331). The spectral lines were observed in the frequency interval ∼160–355 GHz. By means of Local Thermodynamic Equilibrium analyses, applying the rotational diagram method, we studied the excitation conditions of HNCO. The excitation temperature and column density are estimated to be Tex= 58.8 ± 2.7 K and N = (3.7 ± 0.5) × 1015 cm−2, considering beam dilution effects. The derived relative abundance is between (3.8 ± 0.5) × 10−9 and (1.4 ± 0.2) × 10−8. In comparison with other hot molecular cores, our column densities and abundances are in agreement. An update of the internal partition functions of the four CHNO isomers: HNCO; cyanic acid, HOCN; fulminic acid, HCNO; and isofulminic acid, HONC is provided. We also used the astrochemical code NAUTILUS to model and discuss HNCO abundances. The simulations could reproduce the abundances with a simple zero-dimensional model at a temperature of 60 K and for a chemical age of ∼105 yr, which is larger than the estimated dynamical age for G331. This result could suggest the need for a more robust model and even the revision of chemical reactions associated with HNCO.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) 141714/2016-6Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) 001Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) Basal AFB-170002Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) 2014/22095-6Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) 150465/2019-0European Union'sHorizon 2020 research and innovation program under the Marie Sklodowska-Curie grant 872081Spanish National Research, Development, and Innovation plan (RDI plan) PID2019-104002GB-C21Consejeria de Conocimiento, Investigacion y UniversidadJunta de AndaluciaEuropean Commission SOMM17/6105/UGRMinisterio de Ciencia, Innovacion y Universidades COOPB20364Centro de Estudios Avanzados en Fisica, Matematicas y Computacion (CEAFMC) of the University of Huelv

Isocyanic acid (HNCO) in the Hot Molecular Core G331.512-0.103: Observations and Chemical Modelling

The authors thank the anonymous referee for the useful comments that improved the article. CMC acknowledges the support of CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico – Brazil, process number 41714/2016-6. This study was financed in part by the Coordenaçao de Aperfeiçoamento de Pessoal de Níıvel Su- perior – Brasil (CAPES) – Finance Code 001. LB acknowledges support from CONICYT (Comisión Nacional de Investigació Científica y Tecnolóogica) project Basal AFB-170002. EM acknowledges sup- port from the Brazilian agencies FAPESP (Fundaçao de Amparo à Pesquisa do Estado de São Paulo, grant 2014/22095-6) and CNPq (grant 150465/2019-0). MC acknowledges the financial support from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no 872081; from the Spanish National Research, Development, and Innovation plan (RDI plan) under the project PID2019-104002GB-C21; the Consejería de Conocimiento, Investigación y Universidad, Junta de Andalucía and European Regional Development Fund (ERDF), ref. SOMM17/6105/UGR; the Ministerio de Ciencia, Innovación y Universidades (ref. COOPB20364); and by the Centro de Estudios Avanzados en Física, Matemáticas y Computación (CEAFMC) of the University of Huelva