J/A+A/589/A80ivo://CDS.VizieR/J/A+A/589/A80doi:10.26093/cds/vizier.35890080CDSHacar A.Alves J.Forbrich J.Meingast S.Kubiak K.Grossschedl J.2017-01-11T12:14:14Z2016-09-15T14:42:10ZCDS support team

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

cds-question@unistra.fryoung-stellar-objectsradial-velocityWe compare APOGEE radial velocities (RVs) of young stars in the Orion A cloud with CO line gas emission and find a correlation between the two at large scales in agreement with previous studies. However, at smaller scales we find evidence for the presence of a substructure in the stellar velocity field. Using a friends-of-friends approach we identify 37 stellar groups with almost identical RVs. These groups are not randomly distributed, but form elongated chains or strings of stars with five or more members with low velocity dispersion across lengths of 1-1.5pc. The similarity between the kinematic properties of the APOGEE strings and the internal velocity field of the chains of dense cores and fibers recently identified in the dense interstellar medium is striking and suggests that for most of the Orion A cloud, young stars keep memory of the parental gas substructure where they originated.2016A&A...589A..80Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/589/A80CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/589/A80https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/589/A80http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/589/A80https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/589/A80https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/589/A80http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/589/A80GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/589/A80/tablea2 (*APOGEE strings: individual sources (first 10 lines))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/589/A80/tablea2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/589/A80/tablea2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/589/A80/tablea2?GETtext/xml+votable180.050000true83.39283-4.738160.005555555555555556Cone search capability for table J/A+A/589/A80/tablea1 (APOGEE strings: main properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/589/A80/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/589/A80/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/589/A80/tablea1?GETtext/xml+votable180.050000true83.55258-4.759420.0055555555555555566/21425 21428 21430 21436 21438-21439 22804-22805https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/589/A80?format=asciiOpticaldefaultJ/A+A/589/A80/tablea2*APOGEE strings: individual sources (first 10 lines)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAPOGEEAPOGEE designation (2MHHMMSSss+DDMMSSs)meta.id;meta.maincharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latVlsrLSR velocitykm/sphys.veloc;pos.lsrfloate_Vlsrrms uncertainty on Vlsrkm/sstat.error;phys.veloc;pos.lsrfloatStringIDString ID (as in tablea1.dat)meta.id.parentintYSO?[Y/N] Source with Spitzer and/or XMM counterpart?meta.codechar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)degpos.eq.decnullableindexedJ/A+A/589/A80/tablea1APOGEE strings: main propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStringIDAPOGEE string identification bumbermeta.id.parentintGLONString center Galactic longitudedegpos.galactic.lonGLATString center Galactic latitudedegpos.galactic.latNmembNumbe of membersmeta.noteintfYSOfraction of YSOs (i.e., APOGEE sources with Spitzer and/or XMM counterparts) per stringmeta.numberfloatLTotal lengthpcsrc.morph.scLengthfloatDeltaVmaxMaximum velocity difference within a stringkm/sphys.veloc;arith.diff;stat.maxfloatsigmaInternal velocity dispersion per stringkm/sphys.veloc.dispersionfloat<Dnear>Mean distance of the nearest member of the stringpcpos.distancefloatRegionRegion namemeta.id;obs.fieldchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)degpos.eq.decnullableindexed