J/ApJ/696/471ivo://CDS.VizieR/J/ApJ/696/471doi:10.26093/cds/vizier.16960471CDSKnez C.Lacy J.H.Evans N.J.van Dishoeck E.F.Richter M.J.2011-05-30T07:51:03Z2011-05-17T12:45:21ZCDS support team

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

cds-question@unistra.fryoung-stellar-objectsspectroscopyinfrared-sourcesh-ii-regionsWe present high-resolution (R=75000-100000) mid-infrared spectra of the high-mass embedded young star IRS 1 in the NGC 7538 star-forming region. Absorption lines from many rotational states of C_2_H_2_, ^13^C^12^CH_2_, CH_3_, CH_4_, NH_3_, HCN, HNCO, and CS are seen. The gas temperature, column density, covering factor, line width, and Doppler shift for each molecule are derived. All molecules were fit with two velocity components between -54 and -63km/s. We find high column densities (~10^16^cm^-2^) for all the observed molecules compared to values previously reported and present new results for CH_3_ and HNCO. Several physical and chemical models are considered. The favored model involves a nearly edge-on disk around a massive star. Radiation from dust in the inner disk passes through the disk atmosphere, where large molecular column densities can produce the observed absorption line spectrum.2009ApJ...696..471Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/696/471CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/696/471https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/696/471http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/696/471https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/696/471https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/696/471http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/696/471GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/ApJ/696/471/table2Observed linessigmaWavenumber (1/{lambda})cm**-1em.freqdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMoleculeMolecule (1)meta.notecharLineLine identificationmeta.id;spect.linecharEJEnergyKphys.energyfloatBandEnergy bandmeta.code;instr.bandpasschar