J/A+A/635/A73ivo://CDS.VizieR/J/A+A/635/A73doi:10.26093/cds/vizier.36350073CDSBohn A.J.SouthworthJ.GinskiC.Kenworthy M.A.Maxted P.F.L.,Evans D.F.2020-05-07T14:16:48Z2020-03-10T10:20:27ZCDS support team

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

cds-question@unistra.frmultiple-starsexoplanetsMany main-sequence stars are part of multiple systems. The effect of stellar multiplicity on planet formation and migration, however, is poorly understood. We study the multiplicity of stars hosting known transiting extra-solar planets to test competing theories on the formation mechanisms of hot Jupiters. We observed 45 exoplanet host stars using the infrared dual imaging spectrograph (IRDIS) of the Spectro-Polarimetric High-Contrast Exoplanet Research (SPHERE) instrument at the Very Large Telescope (VLT) to search for potential companions. For each identified candidate companion we determined the probability that it is gravitationally bound to its host by performing common proper motion checks and modelling of synthetic stellar populations around the host. In addition, we derived contrast limits as a function of angular separation to set upper limits on further companions in these systems. We converted the derived contrast into mass thresholds using AMES-Cond, AMES-Dusty, and BT-Settl models. We detected new candidate companions around K2-38, WASP-72, WASP-80, WASP-87, WASP-88, WASP-108, WASP-118, WASP-120, WASP-122, WASP123, WASP-130, WASP-131, and WASP-137. The closest candidates were detected at separations of 0.124"+/-0.007" and 0.189"+/-0.003" around WASP-108 and WASP-131; the measured K-band contrasts indicate that these are stellar companions of 0.35+/-0.02M_{sun}_ and 0.62^+0.05^_-0.04_M_{sun}_, respectively. Including the re-detection and confirmation of previously known companions in 13 other systems, we derived a multiplicity fraction of 55.4^+5.9^_-9.4_%. For the representative sub-sample of 40 hot Jupiter host stars among our targets, the derived multiplicity rate is 54.8^+6.3^_-9.9_%. Our data do not confirm any trend that systems with eccentric planetary companions are preferably part of multiple systems. On average, we reached a magnitude contrast of 8.5+/-0.9,mag at an angular separation of 0.5". This allows us to exclude additional stellar companions with masses higher than 0.08M_{sun}_ for almost all observed systems; around the closest and youngest systems, this sensitivity is achieved at physical separations as small as 10au. Our study shows that SPHERE is an ideal instrument for detecting and characterising close companions to exoplanetary host stars.Although the second data release of the Gaia mission also provides useful constraints for some of the systems, the achieved sensitivity provided by the current data release of this mission is not good enough to measure parallaxes and proper motions for all detected candidates. For 14 identified companion candidates further astrometric epochs are required to confirm their common proper motion at 5{sigma} significance.2020A&A...635A..73Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/635/A73CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/492/431 : A planetary-mass companion to a solar-type star (Bohn+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/635/A73https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/635/A73http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/635/A73https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/635/A73https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/635/A73http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/635/A73GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/635/A73/stars (List of studied stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/635/A73/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/635/A73/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/635/A73/stars?GETtext/xml+votable180.050000true240.0335833-23.189250.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/635/A736/12424 16432 16768 17430 17851 18208 26019 30009 30485 31858 34370 35993 39512 43180 43233 43432 43865 44317 46058 47476 48005 48415 48945https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/635/A73?format=asciidefaultJ/A+A/635/A73/det-limContrast limits of our data reduction for all targetsStarStar namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSepProjected separationarcsecpos.angDistancefloatDeltaKsMagnitude contrast Ks bandmagphot.mag;arith.difffloate_DeltaKsUncertainty of magnitude contrast Ks bandmagstat.errorfloatMasslimitAverage mass limit(1.898187x10+27kg)phys.massfloatE_MasslimitUpper mass limit(1.898187x10+27kg)stat.error;stat.maxfloate_MasslimitLower mass limit(1.898187x10+27kg)stat.errorfloatJ/A+A/635/A73/starsList of studied starsSimbadNameSimbad column added by the CDSmeta.idcharRAJ2000Right Ascension (J2000)pos.eq.ra;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar namemeta.id;meta.maincharDEJ2000Declination (J2000)pos.eq.dec;meta.maindet-limDisplay the contrast limits for this starmeta.ref.urlcharNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintsizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitscharJ/A+A/635/A73/table2Astrometry, photometry, background probability and derived masses and effective temperatures of identified candidate companionsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarHost star name around which the companion was detectedmeta.id;meta.maincharCCIDID of the companion candidatemeta.idintDateDate of the observationtime.epochnullableSepSeparation of the CCarcsecpos.angDistancefloate_SepUncertainty of CC separationarcsecstat.errorfloatPAPosition angle of the CCdegpos.posAngfloate_PAUncertainty of the CC PAdegstat.errorfloatKmagK band magnitude of the host star, corrected for contribution of the CCsmagphot.mag;em.IR.KfloatDeltaKMagnitude difference between primary and CCmagphot.mag;arith.difffloate_DeltaKUncertainty in magnitude difference between primary and CCmagstat.errorfloatStatus[ABC] Status of the CC (1)meta.codecharpbgProbability that CC is background objectstat.fit.goodnessdoubleMass? Mass of the CC (2)solMassphys.massfloatnullableB_Mass? Upper threshold for CC masssolMassinstr.sensitivity;stat.maxfloatnullableb_Mass? Lower threshold for CC masssolMassinstr.sensitivity;stat.minfloatnullableTeff? Effective temperature of the CC (2)Kphys.temperature.effectiveintnullableB_Teff? Upper threshold for CC temperatureKinstr.sensitivity;stat.maxintnullableb_Teff? Lower threshold for CC temperatureKinstr.sensitivity;stat.minintnullable