J/A+A/627/L6ivo://CDS.VizieR/J/A+A/627/L6doi:10.26093/cds/vizier.36279006CDSMaud L.T.Cesaroni R.Kumar M.S.N.Rivilla V.M.Ginsburg A.,Klaassen P.D.Harsono D.Sanchez-Monge A.Ahmadi A.Allen V.,Beltran M.T.Beuther H.Galvan-Madrid R.Goddi C.Hoare M.G.,Hogerheijde M.R.Johnston K.G.Kuiper R.Moscadelli L.Peters T.,Testi L.van det Tak F.F.S.de Wit W.J.2019-09-17T09:08:02Z2019-07-09T09:21:05ZCDS support team

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

cds-question@unistra.frinfrared-sourcesmillimeter-astronomysubmillimeter-astronomyinterferometryyoung-stellar-objectsWe present the highest angular resolution (20x15mas - 44x33au) Atacama Large Millimeter/sub-millimeter Array (ALMA) observations currently possible of the proto-O-star G17.64+0.16 in Band 6. The Cycle 5 observations with baselines out to 16 km probes scales <50au and reveal the rotating disc around G17.64+0.16, a massive forming O-type star. The disc has a ring-like enhancement in the dust emission, especially visible as arc structures to the north and south. The Keplerian kinematics are most prominently seen in the vibrationally excited water line, H_2_O (Eu=3461.9K). The mass of the central source found by modelling the Keplerian rotation is consistent with 45+/-10M_{sun}_. The H30alpha (231.9GHz) radio-recombination line and the SiO (5-4) molecular line were detected at up to the 10-sigma level. The estimated disc mass is 0.6-2.6M_{sun}_ under the optically thin assumption. Analysis of the Toomre Q parameter, in the optically thin regime, indicates that the disc stability is highly dependent on temperature. The disc currently appears stable for temperatures >150K, this does not preclude that the substructures formed earlier through disc fragmentation.2019A&A...627L...6Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/627/L6CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/627/L6https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/627/L6http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/627/L6https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/627/L6https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/627/L6http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/627/L6GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/627/L6/list (List of fits files)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/627/L6/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/627/L6/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/627/L6/list?GETtext/xml+votable180.050000true275.60994167-13.5033250.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/627/L66/29504https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/627/L6?format=asciiInfraredMillimeterdefaultJ/A+A/627/L6/listList of fits filesNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintNz? Number of slicesmeta.numberintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainObs.dateObservation date (YYYY-MM-DDThh:mm:ss.sss)stime.epoch;obsnullableRestFreqReference frequency of the cube at Nz=0GHzem.freqfloatdFreq? Frequency resolution for datacubeskHzem.freqfloatnullablesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleDescription of FITS imagemeta.note