J/AJ/157/97ivo://CDS.VizieR/J/AJ/157/97doi:10.26093/cds/vizier.51570097CDSKosiarek M.R.Crossfield I.J.M.Hardegree-Ullman K.K.Livingston J.H.,Benneke B.Henry G.W.Howard W.S.Berardo D.Blunt S.Fulton B.J.,Hirsch L.A.Howard A.W.Isaacson H.Petigura E.A.Sinukoff E.Weiss L.,Bonfils X.Dressing C.D.Knutson H.A.Schlieder J.E.Werner M.,Gorjian V.Krick J.Morales F.Y.Astudillo-Defru N.Almenara J.-M.,Delfosse X.Forveille T.Lovis C.Mayor M.Murgas F.Pepe F.,Santos N.C.Udry S.Corbett H.T.Fors O.Law N.M.Ratzloff J.K.,del Ser D.2019-07-24T13:41:27Z2019-06-07T07:00:43ZCDS support team

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

cds-question@unistra.frm-starsdwarf-starsradial-velocityexoplanetsWe report improved masses, radii, and densities for four planets in two bright M-dwarf systems, K2-3 and GJ3470, derived from a combination of new radial velocity and transit observations. Supplementing K2 photometry with follow-up Spitzer transit observations refined the transit ephemerides of K2-3 b, c, and d by over a factor of 10. We analyze ground-based photometry from the Evryscope and Fairborn Observatory to determine the characteristic stellar activity timescales for our Gaussian Process fit, including the stellar rotation period and activity region decay timescale. The stellar rotation signals for both stars are evident in the radial velocity data and is included in our fit using a Gaussian process trained on the photometry. We find the masses of K2-3 b, K2-3 c, and GJ3470 b to be 6.48_-0.93_^+0.99^, 2.14_-1.04_^+1.08^, and 12.58_-1.28_^+1.31^ M_{Earth}_, respectively. K2-3 d was not significantly detected and has a 3{sigma} upper limit of 2.80 M_{Earth}_. These two systems are training cases for future TESS systems; due to the low planet densities ({rho}<3.7 g/cm^-3^) and bright host stars (K<9 mag), they are among the best candidates for transmission spectroscopy in order to characterize the atmospheric compositions of small planets.2019AJ....157...97Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/157/97CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/546/A27 : Radial velocity and photometry for GJ3470 (Bonfils+, 2012)J/A+A/559/A32 : Light curves of GJ3470b (Nascimbeni+, 2013)J/A+A/559/A33 : Near-IR Spectrophotometry of GJ 3470b (Crossfield+, 2013)J/ApJ/770/95 : g'RcIcJ photometry of the hot Uranus GJ3470b (Fukui+, 2013)J/ApJ/809/77 : Transiting Exoplanet Survey Satellite (TESS) (Sullivan+, 2015)J/A+A/615/A69 : K2-3 system characterized with HARPS-N & HARPS (Damasso+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/157/97https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/157/97http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/157/97https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/157/97https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/157/97http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/157/97GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/AJ/157/97/table4K2-3 HIRES relative RV measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBarycentric Julian Date; TDBdtime.epochdoubleRV[-15.693013/26520.36] Radial velocitym/sphys.veloc;pos.heliocentricdoublee_RV[1.315844/7.07] Uncertainty in RVm/sstat.errordoubleSHK[0.2492/2.341]? S_HK_ indexspect.indexfloatnullableJ/AJ/157/97/table5GJ3470 relative RV measurementsBJDBarycentric Julian Date; TDBdtime.epochdoubleRV[-15.693013/26520.36] Radial velocitym/sphys.veloc;pos.heliocentricdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinte_RV[1.315844/7.07] Uncertainty in RVm/sstat.errordoubleSHK[0.2492/2.341]? S_HK_ indexspect.indexfloatnullableInstInstrument used (HIRES or HARPS) (only in Table 5)instr.setupchar