J/ApJ/785/47ivo://CDS.VizieR/J/ApJ/785/47doi:10.26093/cds/vizier.17850047CDSLafreniere D.Jayawardhana R.van Kerkwijk M.H.Brandeker A.Janson M.2017-07-19T07:21:11Z2017-06-19T15:17:05ZCDS support team

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

cds-question@unistra.frstellar-associationsmultiple-starsinfrared-photometryWe present the results of a multiplicity survey of 91 stars spanning masses of ~0.2-10 M_{sun}_ in the Upper Scorpius star-forming region, based on adaptive optics imaging with the Gemini North telescope. Our observations identified 29 binaries, 5 triples, and no higher order multiples. The corresponding raw multiplicity frequency is 0.37+/-0.05. In the regime where our observations are complete - companion separations of 0.1''-5'' (~15-800 AU) with magnitude limits ranging from K <9.3 at 0.1'' to K<15.8 at 5'' - the multiplicity frequency is 0.27_0.04_^+0.05^. For similar separations, the multiplicity frequency in Upper Scorpius is comparable to that in other dispersed star-forming regions, but is a factor of two to three higher than in denser star-forming regions or in the field. Our sample displays a constant multiplicity frequency as a function of stellar mass. Among our sample of binaries, we find that both wider (>100 AU) and higher-mass systems tend to have companions with lower companion-to-primary mass ratios. Three of the companions identified in our survey are unambiguously substellar and have estimated masses below 0.04 M_{sun}_ (two of them are new discoveries from this survey - 1RXS J160929.1-210524b and HIP 78530B - although we have reported them separately in earlier papers). These three companions have projected orbital separations of 300-900 AU. Based on a statistical analysis factoring in sensitivity limits, we calculate an occurrence rate of 5-40 M_Jup_ companions of ~4.0% for orbital separations of 250-1000 AU, compared to <1.8% at smaller separations, suggesting that such companions are more frequent on wider orbits.2014ApJ...785...47Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/785/47CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/373/95 : ZYJHK survey of Upper Sco association (Lodieu+, 2006)J/ApJ/705/1646 : Debris disks in Upper Sco (Carpenter+, 2009)J/MNRAS/418/1231 : New brown dwarfs in upper Sco (Dawson+, 2011)J/ApJ/758/31 : IR photometry for members of Upper Sco (Luhman+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/785/47https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/785/47http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/785/47https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/785/47https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/785/47http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/785/47GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/785/47/table3 (Sources detected around target stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/785/47/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/785/47/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/785/47/table3?GETtext/xml+votable180.050000true239.2211511-29.21407250.0055555555555555566/29320 42799 42924 42939 42955 42987 42990 44293 44297 44303 44306 44307 44308 44311 44316 44317 44321 44324 44333 44352 44353 44356 44360 44361 44363 44365 44366 44367 44368 44378 44388 44389 44397 44400 44401 44409https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/785/47?format=asciiInfrareddefaultJ/ApJ/785/47/table3Sources detected around target starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintn_Name[F] Note on Name (1)meta.notecharNameSource identifier (2)meta.id;meta.maincharf_Name[eg] Flag on Name (3)meta.codecharSepSeparationarcsecpos.angDistancefloate_SepUncertainty in Sep (4)arcsecstat.errorfloatPAPosition angledegpos.posAngfloate_PAUncertainty in PA (4)degstat.errorfloatDelKmag? K band magnitude differencemagphot.mag;arith.difffloatnullablee_DelKmag? Uncertainty in DelKmagmagstat.error;phot.magfloatnullableEdet? Expected total number (5)meta.numberdoublenullableNdet? Actual number (6)meta.numberintnullableStatusStatus of candidate companion (7)meta.codecharSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main