J/A+A/633/A126ivo://CDS.VizieR/J/A+A/633/A126doi:10.26093/cds/vizier.36330126CDSBusch L.A.Belloche A.Cabrit S.Hennebelle P.Commercon B.2020-01-22T05:59:40Z2020-01-22T06:59:14ZCDS support team

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

cds-question@unistra.frprotostarsyoung-stellar-objectsco-line-emissionOn the basis of its low luminosity, its chemical composition, and the absence of a large-scale outflow, the dense core Cha-MMS1 located in the Chamaeleon I molecular cloud was proposed as a first hydrostatic core (FHSC) candidate a decade ago. Our goal is to test this hypothesis by searching for a slow, compact outflow driven by Cha-MMS1 that would match the predictions of MHD simulations for this short phase of star formation. We use the Atacama Large Millimeter/submillimeter Array (ALMA) to map Cha-MMS1 at high angular resolution in CO 3-2 and ^13^CO 3-2 as well as in continuum emission. We report the detection of a bipolar outflow emanating from the central core, along a (projected) direction roughly parallel to the filament in which Cha-MMS1 is embedded and perpendicular to the large-scale magnetic field. The morphology of the outflow indicates that its axis lies close to the plane of the sky. We measure velocities corrected for inclination of more than 90km/s which is clearly incompatible with the expected properties of a FHSC outflow. Several properties of the outflow are determined and compared to previous studies of Class 0 and Class I protostars. The outflow of Cha-MMS1 has a much smaller momentum force than the outflows of other Class0 protostars. In addition, we find a dynamical age of 200-3000yr indicating that Cha-MMS1 might be one of the youngest ever observed Class 0 protostars. While the existence of the outflow suggests the presence of a disk, no disk is detected in continuum emission and we derive an upper limit of 55au to its radius. We conclude that Cha-MMS1 has already gone through the FHSC phase and is a young Class 0 protostar, but it has not brought its outflow to full power yet.2020A&A...633A.126Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/633/A126CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/564/A99 : Chamaeleon-MMS1 NH_3_ (1,1) and (2,2) maps (Vaisala+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/633/A126https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/633/A126http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/633/A126https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/633/A126https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/633/A126http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/633/A126GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/633/A126/list (List of fits files)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/633/A126/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/633/A126/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/633/A126/list?GETtext/xml+votable180.050000true166.6380417-77.39308330.0055555555555555566/36956https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/633/A126?format=asciiRadiodefaultJ/A+A/633/A126/listList of fits filesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)pos.eq.ra;meta.mainDEJ2000Declination of center (J2000)pos.eq.dec;meta.mainNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintNzNumber of channels along the spectral axismeta.number;phys.atmol.numberintbFreqMinimum frequency of spectral axisGHzem.freq;stat.minfloatBFreqMaximum frequency of spectral axisGHzem.freq;stat.maxfloatdFreqFrequency resolutionkHzem.freqfloatsizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the filemeta.title;meta.file