J/A+A/629/A72ivo://CDS.VizieR/J/A+A/629/A72doi:10.26093/cds/vizier.36290072CDSOrdu M.H.Zingsheim O.Belloche A.Lewen F.Garrod R.T.Menten K.M.,Schlemmer S.Mueller H.S.P.2019-09-16T08:20:26Z2019-09-11T12:54:20ZCDS support team

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

cds-question@unistra.fratomic-physicsSpectra of minor isotopic species of molecules that are abundant in space may also be detectable. Their respective isotopic ratios may provide clues about the formation of these molecules. Emission lines of acetone in the hot molecular core Sagittarius B2(N2) are strong enough to warrant a search for its singly substituted 13C isotopologs. We want to study the rotational spectra of CH_3_^13^C(O)CH_3_ and ^13^CH_3_C(O)CH_3_ and search for them in Sagittarius B2(N2). We investigated the laboratory rotational spectrum of isotopically enriched CH_3_^13^C(O)CH_3_ between 40GHz and 910GHz and of acetone between 36GHz and 910GHz in order to study ^13^CH_3_C(O)CH_3_ in natural isotopic composition. In addition, we searched for emission lines produced by these species in a molecular line survey of Sagittarius B2(N) carried out with the Atacama Large Millimeter/submillimeter Array (ALMA). Discrepancies between predictions of the main isotopic species and the ALMA spectrum prompted us to revisit the rotational spectrum of this isotopolog. We assigned 9711 new transitions of CH_3_^13^C(O)CH_3_ and 63 new transitions of ^13^CH_3_C(O)CH_3_ in the laboratory spectra. More than 1000 additional lines were assigned for the main isotopic species.We modeled the ground state data of all three isotopologs satisfactorily with the ERHAM program. We find that models of the torsionally excited states {nu}_12_=1 and {nu}_17_=1 of CH_3_C(O)CH_3_ improve only marginally. No transition of CH_3_^13^C(O)CH_3_ is clearly detected toward the hot molecular core Sgr B2(N2). However, we report a tentative detection of ^13^CH_3_C(O)CH_3_ with a ^12^C/^13^C isotopic ratio of 27 that is consistent with the ratio previously measured for alcohols in this source. Several dozens of transitions of both torsional states of the main isotopolog are detected as well. Our predictions of CH_3_^13^C(O)CH_3_ and CH_3_C(O)CH_3_ are reliable into the terahertz region. The spectrum of ^13^CH_3_C(O)CH_3_ should be revisited in the laboratory with an enriched sample. The torsionally excited states v_12_=1 and v_17_=1 of CH_3_C(O)CH_3_ were not reproduced satisfactorily in our models. Nevertheless, transitions pertaining to both states could be identified unambiguously in Sagittarius B2(N2).2019A&A...629A..72Ohttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/629/A72CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/629/A72https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/629/A72http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/629/A72https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/629/A72https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/629/A72http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/629/A72GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/629/A72/a12cTransitions included in the fit of the GS of acetone12C (CH_3_C(O)CH_3_)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSigma1First symmetry label of upper and lower statemeta.id;phys.atmol.configurationintSigma2Second symmetry label of upper and lower statemeta.id;phys.atmol.configurationintJ'Upper state J quantum numberphys.atmol.configurationintKa'Upper state Ka quantum numberphys.atmol.qnintKc'Upper state Kc quantum numberphys.atmol.qnintJ"Lower state J quantum numberphys.atmol.configurationintKa"Lower state Ka quantum numberphys.atmol.qnintKc"Lower state Kc quantum numberphys.atmol.qnintFreqObserved transition frequency in MHzMHzem.freqdoubleUncExperimental uncertainty in MHzMHzstat.errorfloat(O-C)Observed minus calculated frequency in MHzMHzstat.fit.residualfloatw? Weight of the component in group of linesstat.weight;phys.atmol.weight;pos.lgfloatnullableDev? Deviation ratio in (O-C)/Uncstat.stdevdoublenullablewDev? Averaged weighted deviation ratio in group of linesstat.stdevfloatnullableNotesSource of data (reference) (1)meta.notecharJ/A+A/629/A72/a1-13cTransitions included in the fit of the GS of acetone-1-13C (^13^CH_3_C(O)CH_3_)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSigma1First symmetry label of upper and lower statemeta.id;phys.atmol.configurationintSigma2Second symmetry label of upper and lower statemeta.id;phys.atmol.configurationintJ'Upper state J quantum numberphys.atmol.configurationintKa'Upper state Ka quantum numberphys.atmol.qnintKc'Upper state Kc quantum numberphys.atmol.qnintJ"Lower state J quantum numberphys.atmol.configurationintKa"Lower state Ka quantum numberphys.atmol.qnintKc"Lower state Kc quantum numberphys.atmol.qnintFreqObserved transition frequency in MHzMHzem.freqdoubleUncExperimental uncertainty in MHzMHzstat.errorfloat(O-C)Observed minus calculated frequency in MHzMHzstat.fit.residualfloatw? Weight of the component in group of linesstat.weight;phys.atmol.weight;pos.lgfloatnullableDev? Deviation ratio in (O-C)/Uncstat.stdevdoublenullablewDev? Averaged weighted deviation ratio in group of linesstat.stdevfloatnullableNotesSource of data (reference) (1)meta.notecharJ/A+A/629/A72/a12cv121Transitions included in the fit of v12=1 of acetone-12C (CH_3_C(O)CH_3_-v12=1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSigma1First symmetry label of upper and lower statemeta.id;phys.atmol.configurationintSigma2Second symmetry label of upper and lower statemeta.id;phys.atmol.configurationintJ'Upper state J quantum numberphys.atmol.configurationintKa'Upper state Ka quantum numberphys.atmol.qnintKc'Upper state Kc quantum numberphys.atmol.qnintJ"Lower state J quantum numberphys.atmol.configurationintKa"Lower state Ka quantum numberphys.atmol.qnintKc"Lower state Kc quantum numberphys.atmol.qnintFreqObserved transition frequency in MHzMHzem.freqdoubleUncExperimental uncertainty in MHzMHzstat.errorfloat(O-C)Observed minus calculated frequency in MHzMHzstat.fit.residualfloatw? Weight of the component in group of linesstat.weight;phys.atmol.weight;pos.lgfloatnullableDev? Deviation ratio in (O-C)/Uncstat.stdevdoublenullablewDev? Averaged weighted deviation ratio in group of linesstat.stdevfloatnullableNotesSource of data (reference) (1)meta.notecharJ/A+A/629/A72/a12cv171Transitions included in the fit of v17=1 of acetone-12C (CH_3_C(O)CH_3_-v17=1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSigma1First symmetry label of upper and lower statemeta.id;phys.atmol.configurationintSigma2Second symmetry label of upper and lower statemeta.id;phys.atmol.configurationintJ'Upper state J quantum numberphys.atmol.configurationintKa'Upper state Ka quantum numberphys.atmol.qnintKc'Upper state Kc quantum numberphys.atmol.qnintJ"Lower state J quantum numberphys.atmol.configurationintKa"Lower state Ka quantum numberphys.atmol.qnintKc"Lower state Kc quantum numberphys.atmol.qnintFreqObserved transition frequency in MHzMHzem.freqdoubleUncExperimental uncertainty in MHzMHzstat.errorfloat(O-C)Observed minus calculated frequency in MHzMHzstat.fit.residualfloatw? Weight of the component in group of linesstat.weight;phys.atmol.weight;pos.lgfloatnullableDev? Deviation ratio in (O-C)/Uncstat.stdevdoublenullablewDev? Averaged weighted deviation ratio in group of linesstat.stdevfloatnullableNotesSource of data (reference) (1)meta.notecharJ/A+A/629/A72/a2-13cTransitions included in the fit of the GS of acetone-2-13C (CH_3_13C(O)CH_3_)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSigma1First symmetry label of upper and lower statemeta.id;phys.atmol.configurationintSigma2Second symmetry label of upper and lower statemeta.id;phys.atmol.configurationintJ'Upper state J quantum numberphys.atmol.configurationintKa'Upper state Ka quantum numberphys.atmol.qnintKc'Upper state Kc quantum numberphys.atmol.qnintJ"Lower state J quantum numberphys.atmol.configurationintKa"Lower state Ka quantum numberphys.atmol.qnintKc"Lower state Kc quantum numberphys.atmol.qnintFreqObserved transition frequency in MHzMHzem.freqdoubleUncExperimental uncertainty in MHzMHzstat.errorfloat(O-C)Observed minus calculated frequency in MHzMHzstat.fit.residualfloatw? Weight of the component in group of linesstat.weight;phys.atmol.weight;pos.lgfloatnullableDev? Deviation ratio in (O-C)/Uncstat.stdevdoublenullablewDev? Averaged weighted deviation ratio in group of linesstat.stdevfloatnullableNotesSource of data (reference) (1)meta.notechar