J/A+A/644/A84ivo://CDS.VizieR/J/A+A/644/A84doi:10.26093/cds/vizier.36440084CDSMininni C.Beltran M.T.Rivilla V.M.Sanchez-Monge A.Fontani F.,Moeller T.Cesaroni R.Schilke P.Viti S.Jimenez-Serra I.Colzi L.,Lorenzani A.Testi L.2021-02-16T12:08:39Z2020-12-02T08:09:46ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frstar-forming-regionsradio-astronomyWe present an unbiased spectral survey of one of the most chemically rich hot molecular cores located outside the Galactic Center, in the high-mass star-forming region G31.41+0.31. In this first paper, we discuss the detection and relative abundances of the three isomers of C_2_H_4_O_2_: methyl formate, glycolaldehyde, and acetic acid. Observations were carried out with the ALMA interferometer, covering all of band 3 (~32GHz bandwidth) with an angular resolution of 1.2"x1.2" (~4400aux4400au) and a spectral resolution of ~0.488MHz. The transitions of the three molecules have been analyzed with the software XCLASS to determine the physical parameters of the emitted gas. The comparison with chemical models in literature suggests the necessity of grain-surface routes for the formation of methyl formate in G31, while for glycolaldehyde both grain-surface reactions and gas-phase chemistry could be able to explain the observations.2020A&A...644A..84Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/644/A84CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/644/A84https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/644/A84http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/644/A84https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/644/A84https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/644/A84http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/644/A84GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapRadiodefaultJ/A+A/644/A84/aceticIdentified transitions of acetic acidrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFlagFlag (1)meta.code.errorcharStateMolecular vibrational statephys.atmol.configurationcharFreqRest frequencyMHzem.freqdoubleAEEinstein coefficients**-1phys.atmol.transProbdoubleEuUpper state energy E_u_Kphys.energyfloatguDegeneracy of the upper state g_u_phys.electron.degenintJuUpper state quantum number Jphys.atmol.configurationintKauUpper state quantum number K_a_phys.mol.qnintKcuUpper state quantum number K_c_phys.mol.qnintA1/A2/EuState A1/A2/Ephys.atmol.configurationcharJlLower state quantum number Jphys.atmol.configurationintKalLower state quantum number K_a_phys.mol.qnintKclLower state quantum number K_c_phys.mol.qnintA1/A2/ElState A1/A2/Ephys.atmol.configurationchartauOptical depth at the center of the linephys.absorption.opticalDepthdoubleJ/A+A/644/A84/glycolIdentified transitions of glycolaldehyderecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFlagFlag (1)meta.code.errorcharStateMolecular vibrational statephys.atmol.configurationcharFreqRest frequencyMHzem.freqdoubleAEEinstein coefficients**-1phys.atmol.transProbdoubleEuUpper state energy E_uKphys.energyfloatguDegeneracy of the upper state g_u_phys.electron.degenintJuUpper state quantum number Jphys.atmol.configurationintKauUpper state quantum number K_a_phys.mol.qnintKcuUpper state quantum number K_c_phys.mol.qnintJlLower state quantum number Jphys.atmol.configurationintKalLower state quantum number K_a_phys.mol.qnintKclLower state quantum number K_c_phys.mol.qnintTauOptical depth at the center of the linephys.absorption.opticalDepthdoubleJ/A+A/644/A84/methylIdentified transitions of methyl formaterecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFlagFlag (1)meta.code.errorcharStateMolecular vibrational statephys.atmol.configurationcharFreqRest frequencyMHzem.freqdoubleAEEinstein coefficients**-1phys.atmol.transProbdoubleEuUpper state energy E_uKphys.energyfloatguDegeneracy of the upper state g_uphys.electron.degenintJuUpper state quantum number Jphys.atmol.configurationintKauUpper state quantum number K_aphys.mol.qnintKcuUpper state quantum number K_cphys.mol.qnintA/EuState A/Ephys.atmol.configurationcharJlLower state quantum number Jphys.atmol.configurationintKalLower state quantum number K_aphys.mol.qnintKclLower state quantum number K_cphys.mol.qnintA/ElState A/Ephys.atmol.configurationchartauOptical depth at the center of the linephys.absorption.opticalDepthdouble