J/AJ/162/294ivo://CDS.VizieR/J/AJ/162/294doi:10.26093/cds/vizier.51620294CDSMurphy J.M.A.Kosiarek M.R.Batalha N.M.Gonzales E.J.Isaacson H.,Petigura E.A.Weiss L.M.Grunblatt S.K.Ciardi D.R.Fulton B.,Hirsch L.A.Behmard A.Rosenthal L.J.2024-11-06T20:17:12Z2022-03-25T07:14:57ZCDS support team

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

cds-question@unistra.frexoplanetsvisible-astronomyspectroscopyradial-velocityWe combine multiple campaigns of K2 photometry with precision radial velocity measurements from Keck-HIRES to measure the masses of three sub-Neptune-sized planets. We confirm the planetary nature of the massive sub-Neptune K2-182b (P_b_=4.7days, R_b_=2.69R{Earth}) and derive refined parameters for K2-199b and c (P_b_=3.2days, R_b_=1.73R{Earth} and P_c_= 7.4days, R_c_=2.85R{Earth}). These planets provide valuable data points in the mass-radius plane, especially as TESS continues to reveal an increasingly diverse sample of sub-Neptunes. The moderately bright (V=12.0mag) early K dwarf K2-182 (EPIC 211359660) was observed during K2 campaigns 5 and 18. We find that K2-182b is potentially one of the densest sub-Neptunes known to date (20{+/-}5M{Earth} and 5.6{+/-}1.4g/cm^3^). The K5V dwarf K2-199 (EPIC212779596; V=12.3mag), observed in K2 campaigns 6 and 17, hosts two recently confirmed planets. We refine the orbital and planetary parameters for K2-199b and c by modeling both campaigns of K2 photometry and adding 12 Keck-HIRES measurements to the existing radial velocity data set (N=33). We find that K2-199b is likely rocky, at 6.9{+/-}1.8M{Earth} and 7.2_-2.0_^+2.1^g/cm^3^, and that K2-199c has an intermediate density at 12.4{+/-}2.3M{Earth} and 2.9_-0.6_^+0.7^g/cm^3^. We contextualize these planets on the mass-radius plane, discuss a small but intriguing population of "superdense" sub-Neptunes (R_p_<3R{Earth}, M_p_>20M{Earth}), and consider our prospects for the planets' atmospheric characterization.2021AJ....162..294Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/162/294CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)VI/120 : High-resolution synthetic stellar library (Coelho+, 2005)J/A+A/541/A9 : M dwarfs activity and radial velocity (Gomes da Silva+, 2012)J/PASP/124/1279 : Q3 Kepler's combined photometry (Christiansen+, 2012)J/ApJS/224/2 : K2 EPIC stellar properties for 138600 targets (Huber+, 2016)J/AJ/153/71 : Kepler follow-up observation program I. Imaging (Furlan+, 2017)J/AJ/154/109 : California-Kepler Survey. III. Planet radii (Fulton+, 2017)J/AJ/154/5 : Transit timing variations of 145 Kepler planets (Hadden+, 2017)J/ApJ/836/167 : K2 planetary syst. around low-mass stars. I. (Dressing+, 2017)J/ApJ/866/99 : Revised radii KIC stars & planets using GaiaDR2 (Berger+, 2018)J/ApJS/239/5 : Variable stars and cand. planets from K2 (Crossfield+, 2018)J/MNRAS/474/2094 : Inferring proba. stellar rotation periods (Angus+, 2018)J/AJ/161/36 : 117 exoplanets habitable zone with Kepler DR25 (Bryson+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/162/294https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/162/294http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/162/294https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/162/294https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/162/294http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/162/294GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/162/294/table6K2-182 radial velocitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2458568/2458633] Barycentric Julian Datedtime.epochdoubleRVel[-14.9/8.79] Radial velocitym/sphys.veloc;pos.heliocentricfloate_RVel[1.4/1.7] Uncertainty in RVel (1)m/sstat.error;spect.dopplerVelocfloatInstInstrumentmeta.id;instrcharJ/AJ/162/294/table7K2-199 radial velocitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2457562/2458634] Barycentric Julian Datedtime.epochdoubleRVel[-19.2/13.7] Radial velocitym/sphys.veloc;pos.heliocentricfloate_RVel[1.3/2.3] Uncertainty in RVel (1)m/sstat.error;spect.dopplerVelocfloatInstInstrumentmeta.id;instrchar