J/A+A/704/A170ivo://CDS.VizieR/J/A+A/704/A170CDSRodrigues T.Bouy H.Raymond S.N.Martin E.L.Bertin E.M.,Olivares J.Barrado D.Huelamo N.Tamura M.Miret Roig N.,Galli P.A.B.Cuillandre J.-C.2026-03-02T06:25:50Z2025-12-11T09:13:36ZCDS support team

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

cds-question@unistra.frlate-type-starsyoung-stellar-objectsinfrared-photometryFree-floating planetary-mass objects (FFPs) have been detected through direct imaging within several young, nearby star-forming regions. The properties of circumstellar disks around these objects may provide a valuable probe into their origin, but is currently limited by the small sizes of the sample explored. We aim to perform a statistical study of the occurrence of circumstellar disks down to the planetary-mass regime. We performed a systematic survey of disks among the population identified in the 5-10Myr-old Upper Scorpius association (USC), restricted to members outside the younger, embedded Ophiuchus region and with estimated masses below 10^5^M_Jup_. We took advantage of unWISE photometry to search for mid-infrared excesses in the WISE (W1-W2) color. We implemented a Bayesian outlier detection method that models the photospheric sequence and computes excess probabilities for each object, enabling statistically sound estimation of disk fractions. We explore disk fractions across an unprecedentedly fine mass grid, reaching down to objects as low as ~6M_Jup_ assuming 5Myr or ~8M_Jup_ assuming 10Myr, thus extending the previous lower boundary of disk fraction studies. Depending on the age, our sample includes between 17 and 40 FFPs. We confirm that the disk fraction steadily rises with decreasing mass and exceeds 30% near the substellar-to-planetary mass boundary at ~13M_Jup_. We find hints of a possible flattening in this trend around 25-45M_Jup_, potentially signaling a transition in the dominant formation processes. This change of trend should be considered with caution and needs to be confirmed with more sensitive observations. Our results are consistent with the gradual dispersal of disks over time, as disk fractions in Upper Scorpius appear systematically lower than those in younger regions.2025A&A...704A.170Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/704/A170CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/667/A163 : Upper Scorpius and Ophiuchus members (Miret-Roig+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/704/A170https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/704/A170http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/704/A170https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/704/A170https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/704/A170http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/704/A170GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/704/A170/tablea2 (Excess probabilities and unWISE W1/W2 photometry of USC members)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/704/A170/tablea2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/704/A170/tablea2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/704/A170/tablea2?GETtext/xml+votable180.050000true242.564225-29.398991940.0055555555555555564/2769 2772 5/10734-10735 11075 11084-11085 11092 11094 11096-11097 6/29347 29353-29356 30721-30722 30724 30728 42906 42924 42927-42929 42931-42932 42934-42935 42984 42986-42987 42990-42991 42998 43000 43002-43003 43005-43007 44288-44289 44291-44294 44297 44325 44349-44350 44373-44374 44380-44382 44392 44394 44397 44399-44402 44404 44408-44410 44481https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/704/A170?format=asciiInfrareddefaultJ/A+A/704/A170/tablea2Excess probabilities and unWISE W1/W2 photometry of USC membersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/3455] Member identification number from Miret Roig et al. (2022A&A...667A.163M, Cat. J/A+A/667/A163)meta.id;meta.mainintRA_ICRSRight ascension (ICRS) at Ep=2016.0degpos.eq.ra;meta.mainDE_ICRSDeclination (ICRS) at Ep=2016.0degpos.eq.dec;meta.maindDistance from Gaia DR3pcpos.distancefloate_dUncertainty on distancepcstat.errorfloatMass5MyrMass estimate assuming 5Myr from Miret Roig et al. (2022, Cat. J/A+A/667/A163)(1.898187x10+27kg)phys.massdoubleMass10MyrMass estimate assuming 10Myr from Miret Roig et al. (2022, Cat. J/A+A/667/A163)(1.898187x10+27kg)phys.massdoubleW1magunWISE/W1 magnitudemagphot.mag;em.IR.3-4umdoublee_W1magUncertainty on unWISE/W1 magnitudemagstat.error;phot.magdoubleW2magunWISE/W2 magnitudemagphot.mag;em.IR.4-8umdoublee_W2magUncertainty on unWISE/W2 magnitudemagstat.error;phot.magdoublefWISE[0/1] Flag: possible contamination in unWISE images (1 = flagged, 0 = clean)meta.codeintpexc5Myr? Excess probability (5Myr, keeping flagged sources)stat.fit.goodnessfloatnullablepexc10Myr? Excess probability (10Myr, keeping flagged sources)stat.fit.goodnessfloatnullablepexc5Myrw? Excess probability (5Myr, excluding flagged sources)stat.fit.goodnessfloatnullablepexc10Myrw? Excess probability (10Myr, excluding flagged sources)stat.fit.goodnessfloatnullable