J/A+A/558/A24ivo://CDS.VizieR/J/A+A/558/A24doi:10.26093/cds/vizier.35580024CDSBoley P.A.Linz H.van Boekel R.Henning T.Feldt M.Kaper L.,Leinert C.Mueller A.Pascucci I.Roberto M.Stecklum B.,Waters L.B.F.M.Zinnecker H.2017-12-18T07:57:22Z2013-09-27T09:11:59ZCDS support team

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

cds-question@unistra.frsurveysyoung-stellar-objectsinterferometryDue to inherent difficulties involved in observations and theoretical/numerical simulations of the formation of massive stars, an understanding of the early evolutionary phases of these objects remains elusive. In particular, observationally probing circumstellar material at distances <~100AU from the central star is exceedingly difficult, as such objects are rare (and thus, on average, far away) and typically deeply embedded. Long-baseline mid-infrared interferometry provides one way of obtaining the necessary spatial resolution at appropriate wavelengths to study this class of objects, however, interpreting such observations is often difficult due to sparse spatial-frequency coverage. We aim to characterize the distribution and composition of circumstellar material around young massive stars, and to investigate exactly which physical structures in these objects are probed by long-baseline mid-infrared interferometric observations. We use the two-telescope interferometric instrument MIDI of the Very Large Telescope Interferometer of the European Southern Observatory to observe a sample of 24 intermediate- and high-mass young stellar objects in the N band (8-13 micron). We had successful fringe detections for 20 objects, and present spectrally-resolved correlated fluxes and visibility levels for projected baselines of up to 128m. We fit the visibilities with geometric models to derive the sizes of the emitting regions, as well as the orientation and elongation of the circumstellar material. A subset of 14 objects show the 10 micron silicate feature in absorption in the total and correlated flux spectra. For 13 of these objects, we were able to fit the correlated flux spectra with a simple absorption model, allowing us to constrain the composition and absorptive properties of the circumstellar material.2013A&A...558A..24Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/558/A24CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/115/285 : Catalogue of massive young stellar objects (Chan+, 1996)J/A+A/481/345 : SED evolution in massive YSOs (Molinari,+ 2008)J/ApJ/699/150 : Spectral classifications of massive YSOs in LMC (Seale+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/558/A24https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/558/A24http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/558/A24https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/558/A24https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/558/A24http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/558/A24GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/558/A24/list (List of FITS files)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/558/A24/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/558/A24/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/558/A24/list?GETtext/xml+votable180.050000true275.60992-13.503340.0055555555555555566/21439 21458 23636-23637 23646 23969 28891 29116 29504 30242 41655 41676-41677 42392 42448 43235 47828https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/558/A24?format=asciiOpticaldefaultJ/A+A/558/A24/listList of FITS filesSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainNuvNumber of uv pointsmeta.numberintFileNameName of OI-FITS file in subdirectory fitsmeta.id;meta.filecharTargetTarget namemeta.id;meta.maincharFITSDownload the OI-FITS file relative to this YSOmeta.ref.urlchar