J/A+A/591/A75ivo://CDS.VizieR/J/A+A/591/A75doi:10.26093/cds/vizier.35910075CDSKolesnikova L.Alonso J.L.Bermudez C.Alonso E.R.Tercero B.,Cernicharo J.Guillemin J.-C.2018-06-11T09:01:31Z2016-06-17T08:05:40ZCDS support team

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

cds-question@unistra.frinterstellar-mediumspectroscopyatomic-physicsThe recent discovery of methyl isocyanate (CH_3_NCO) in Sgr B2(N) and Orion KL makes methyl cyanate (CH_3_OCN) a potential molecule in the interstellar medium. The aim of this work is to fulfill the first requirement for its unequivocal identification in space, i.e. the availability of transition frequencies with high accuracy. The room-temperature rotational spectrum of methyl cyanate was recorded in the millimeter wave domain from 130 to 350GHz. All rotational transitions revealed A-E splitting owing to methyl internal rotation and were globally analyzed using the ERHAM program. The data set for the ground torsional state of methyl cyanate exceeds 700 transitions within J"=10-35 and K"a=0-13 and newly derived spectroscopic constants reproduce the spectrum close to the experimental uncertainty. Spectral features of methyl cyanate were then searched for in Orion KL, Sgr B2(N), B1-b, and TMC-1 molecular clouds. Upper limits to the column density of methyl cyanate are provided.2016A&A...591A..75Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/591/A75CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/591/A75https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/591/A75http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/591/A75https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/591/A75https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/591/A75http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/591/A75GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/591/A75/tables1Observed rotational transition frequencies of methyl cyanate in the ground torsional staterecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs/PredDisplay observed and predicted frequencies for this transitionmeta.ref.urlcharSigma[0/1] Symmetry number (1)meta.id;meta.mainintJ1Upper state J quantum number (J')phys.atmol.configurationintKa1Upper state Ka quantum number (Ka')phys.atmol.qnintKc1Upper state Kc quantum number (Kc')phys.atmol.qnintJ0Lower state J quantum number (J")phys.atmol.configurationintKa0Lower state Ka quantum number (Ka")phys.atmol.qnintKc0Lower state Kc quantum number (Kc")phys.atmol.qnintFreqObsObserved transition frequencyMHzem.freqdoubleO-CObserved minus calculated frequencyMHzem.freq;stat.fit.omcfloatCommentComment (2)meta.notecharJ/A+A/591/A75/tables2Predicted rotational transition frequencies of methyl cyanate in the ground torsional staterecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs/PredDisplay observed and predicted frequencies for this transitionmeta.ref.urlcharSigma[0/1] Symmetry number (1)meta.id;meta.mainintJ1Upper state J quantum number (J')phys.atmol.configurationintKa1Upper state Ka quantum number (Ka')phys.atmol.qnintKc1Upper state Kc quantum number (Kc')phys.atmol.qnintJ0Lower state J quantum number (J")phys.atmol.configurationintKa0Lower state Ka quantum number (Ka")phys.atmol.qnintKc0Lower state Kc quantum number (Kc")phys.atmol.qnintFreqPredPredicted frequencyMHzem.freqdoublee_FreqPredUncertainty of the predicted frequency (2)MHzstat.errorfloatSmu2Intensity (3)D**2spect.line.intensitydoubleE1Upper level energy (E') (4)cm**-1phys.energy;phys.atmol.levelfloatE0Lower level energy (E")cm**-1phys.energy;phys.atmol.levelfloat