J/A+A/641/A170ivo://CDS.VizieR/J/A+A/641/A170doi:10.26093/cds/vizier.36410170CDSSestovic M.Demory B.-O.2022-03-28T14:47:21Z2020-09-28T07:41:54ZCDS support team

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

cds-question@unistra.frphotometrym-starslate-type-starsexoplanetsWith the discovery of a planetary system around the ultracool dwarf TRAPPIST-1, there has been a surge of interest in such stars as potential planet hosts. Planetary systems around ultracool dwarfs represent our best chance of characterising temperate rocky-planet atmospheres with the James Webb Space Telescope. However, TRAPPIST-1 remains the only known system of its kind and the occurrence rate of planets around ultracool dwarfs is still poorly constrained. We seek to perform a complete transit search on the ultracool dwarfs observed by NASA's K2 mission, and use the results to constrain the occurrence rate of planets around these stars. We filter and characterise the sample of ultracool dwarfs observed by K2 by fitting their spectral energy distributions and using parallaxes from Gaia. We build an automatic pipeline to perform photometry, detrend the light curves, and search for transit signals. Using extensive injection-recovery tests of our pipeline, we compute the detection sensitivity of our search, and thus the completeness of our sample. We infer the planetary occurrence rates within a hierarchical Bayesian model (HBM) to treat uncertain planetary parameters.With the occurrence rate parametrised by a step-wise function, we present a convenient way to directly marginalise over the second level of our HBM (the planetary parameters). Our method is applicable generally and can greatly speed up inference with larger catalogues of detected planets. We detect one planet in our sample of 702 ultracool dwarfs: a previously validated mini-Neptune. We thus infer a mini-Neptune (2-4R_{Earth}_) occurrence rate of {eta}=0.20^+0.16^_0.11_ within orbital periods of 1-20 days. For super-Earths (1-2R_{Earth}_) and ice or gas giants (4-6R_{Earth}_) within 1-20 days, we place 95% credible intervals of {eta}<1.14 and {eta}<0.29, respectively. If TRAPPIST-1-like systems were ubiquitous, we would have a 96% chance of finding at least one.2020A&A...641A.170Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/641/A170CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/641/A170https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/641/A170http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/641/A170https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/641/A170https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/641/A170http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/641/A170GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/641/A170/target (All K2 target stars used)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/641/A170/target?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/641/A170/target?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/641/A170/target?GETtext/xml+votable180.050000true183.9557811-0.61076310.0055555555555555565/112-113 115-116 118 1174-1175 1177 1179-1182 4326 4506 4709 6859 6866 6873 6/272 281 315 322 340 342 346 366-369 378 382 410 439 457-459 471 476 478 480-481 483-485 496 1031 1065 1073 1075 4246-4247 4251-4253 4263 4274 4299 4330 4335 4350-4351 4521 4523 4536 4630 4635 4637 4671-4673 4675-4676 4678-4680 4683-4685 4687 4689-4691 4693-4694 4704-4705 4707 4713-4714 4732-4734 4801-4802 4817 4820 4867 4872-4873 4875 4878 4886 4889 4891-4892 4896-4898 4900 4902-4903 4906 17149-17150 17294-17295 17303 17310 17313 17316-17317 17320-17321 17326 17332 17998-17999 18006 18008 18010 18013 18018-18020 18023 18112 18138 18225 18478 18482 18511 18513 18516-18517 18519-18520 18522 18525 18533 18538 18542 18544 18571 18625 18642 18665 18688-18689 18719 18726 18741-18742 18749-18751 18786 18788 18792-18793 18795 18798 18834-18835 18840 18842-18843 18846 18865-18866 18869 18881-18882 23471 23479 23523 23526 23531-23532 23547 23550 24105 24110 25433 25443 25456 25463 25549 25558-25559 25588-25590 25619 25674 25712 25807 25818 25823 25843-25844 25846-25847 25849 25852-25853 25992-25994 26016-26018 26158 26181 26192 26210 26248 26251-26252 26256 26263-26264 26267 26275-26276 26282 26293 26300 26307 27046 27057-27059 27066 27106 27113 27115 27229 27392-27393 27395 27398-27400 27405 27414 27418 27420-27422 27426-27427 27433 27443 27446-27448 27450 27456 27458 27462 27469 27488-27489 27497 27510 27514 27518 27525 27527 27536 27548 27588 27590-27591 28847 44362 44416 44421 44456 44486 44718 44778 448071.5062136169708525e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/641/A170?format=asciidefaultJ/A+A/641/A170/targetAll K2 target stars used2MASS2MASS identifiermeta.idcharSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintEpicK2's EPIC identifiermeta.id;meta.mainlongCampaignK2's observation campaignobs.param;obsintdtcdppDetrended CDPP of light curvephot.magdoubledtpv? Detrended PV of light curvephot.magdoublenullableMstarfitStellar mass from fitted spectral type (1)solMassphys.massfloatRstarfitStellar radius from fitted spectral type (1)solRadphys.size.radiusfloatTefffit? Effective temperature from fitted spectral type (1)Kphys.temperature.effectivefloatnullableMstarStellar masssolMassphys.massfloatRstarStellar radiussolRadphys.size.radiusfloatRAdeg? Gaia DR2 right ascension (ICRS) at Ep=2015.5degpos.eq.ranullableDEdeg? Gaia DR2 declination (ICRS) at Ep=2015.5degpos.eq.decnullableGmag? Gaia DR2 G magnitudemagphot.mag;em.optdoublenullablePlx? Gaia DR2 parallaxmaspos.parallaxdoublenullablepmRA*? Gaia DR2 proper motion along RA, pmRA*cosDEmas/yrpos.pm;pos.eq.radoublenullablepmDE? Gaia DR2 proper motion along DEmas/yrpos.pm;pos.eq.decdoublenullableGaiaDR2? Gaia DR2 source IDmeta.idnullableggStelIndex? gg stellar index (2)spect.indexfloatnullableggStelNum? gg stellar number (2)meta.idfloatnullableDEpred? Predicted declination during the K2 observation, calculated with Gaia proper motionsdegpos.eq.decnullableRApred? Predicted right ascension during the K2 observation, calculated with Gaia proper motionsdegpos.eq.ranullableJmag? 2MASS J magnitudemagphot.mag;em.IR.JdoublenullablevosaD? Distance obtained from the VOSA SED fitkpcpos.distancedoublenullablee_vosaD? Distance error obtained from the VOSA SED fitkpcstat.errordoublenullablee_vosaFtot? Total flux error obtained from the VOSA SED fitstat.errordoublenullablevosaFtot? Total flux obtained from the VOSA SED fitphot.flux.densitydoublenullablevosaLbol? Bolometric luminosity obtained from the VOSA SED fitphys.luminositydoublenullablee_vosaLbol? Bolometric luminosity error obtained from the VOSA SED fitstat.errordoublenullablevosaRstar? Stellar radius parameters obtained from the VOSA SED fitsolRadphys.size.radiusdoublenullablee_vosaRstar? Stellar radius error parameters obtained from the VOSA SED fitsolRadstat.errordoublenullablevosaTeff? Effective temperature obtained from the VOSA SED fitKphys.temperature.effectivefloatnullablee_vosaTeff? Effective temperature error obtained from the VOSA SED fitKstat.errorfloatnullable_RAPositions from EPIC (right ascension part)degpos.eq.ra;meta.main_DEPositions from EPIC (declination part)degpos.eq.dec;meta.mainLCShow the light curvesmeta.ref.urlcharFileNameName of the light curve file in subdirectory lcmeta.id;meta.filechardtkernel[c pq] Gaussian Process kernel used in detrending, qp is "quasiperiodic", c is "classic". See paper.meta.codecharSpTypefitSpectral type from fitted spectral type (1)src.spTypecharGaiaFound[False/True ] Found in Gaia DR2 ?meta.codecharggFound[False/True ] Found in gg (2)meta.codecharggNamegg name (JHHMM-DDMM) (2)meta.idcharggSpTypegg spectral type (2)src.spTypecharggClassgg luminosity class (2)src.class.luminositycharProgramIDProgram ID(s)meta.id;obscharirm[True] IRM validmeta.codecharultracool[True] Ultracool validmeta.codechardtFlag[False/True ] dt flagmeta.codecharirmFlag[False/True ] IRM flagmeta.codechar