J/AJ/163/41ivo://CDS.VizieR/J/AJ/163/41doi:10.26093/cds/vizier.51630041CDSNava C.Lopez-Morales M.Mortier A.Zeng LiGiles H.A.C.Bieryla A.,Vanderburg A.Buchhave L.A.Poretti E.Saar S.H.Dumusque X.,Latham D.W.Charbonneau D.Damasso M.Bonomo A.S.Lovis C.,Collier Cameron A.Eastman J.D.Sozzetti A.Cosentino R.Pedani M.,Pepe F.Molinari E.Sasselov D.Mayor M.Stalport M.Malavolta L.,Rice K.Watson C.A.Martinez Fiorenzano A.F.Di Fabrizio L.2022-09-30T22:09:00Z2022-04-22T07:41:23ZCDS support team

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

cds-question@unistra.frexoplanetsg-starsvisible-astronomyspectroscopyphotometryradial-velocityWe present mass and radius measurements of K2-79b and K2-222b, two transiting exoplanets orbiting active G-type stars observed with HARPS-N and K2. Their respective 10.99day and 15.39day orbital periods fall near periods of signals induced by stellar magnetic activity. The two signals might therefore interfere and lead to an inaccurate estimate of exoplanet mass. We present a method to mitigate these effects when radial velocity (RV) and activity-indicator observations are available over multiple observing seasons and the orbital period of the exoplanet is known. We perform correlation and periodogram analyses on subsets composed of each target's two observing seasons, in addition to the full data sets. For both targets, these analyses reveal an optimal season with little to no interference at the orbital period of the known exoplanet. We make a confident mass detection of each exoplanet by confirming agreement between fits to the full RV set and the optimal season. For K2-79b, we measure a mass of 11.8{+/-}3.6M{Earth} and a radius of 4.09{+/-}0.17R{Earth}. For K2-222b, we measure a mass of 8.0{+/-}1.8M{Earth} and a radius of 2.35{+/-}0.08R{Earth}. According to model predictions, K2-79b is a highly irradiated Uranus analog and K2-222b hosts significant amounts of water ice. We also present a RV solution for a candidate second companion orbiting K2-222 at 147.5days.2022AJ....163...41Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/163/41CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)I/322 : UCAC4 Catalogue (Zacharias+, 2012)J/A+A/526/A99 : Metal-poor solartype stars spectroscopy & masses (Sousa+, 2011)J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)J/other/Nat/486.375 : Stellar parameters of KOI stars (Buchhave+, 2012)J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)J/A+A/585/A135 : HD175607 RV, logRHK and Halpha index (Mortier+, 2016)J/AJ/152/204 : HARPS-N radial velocities of HD 179070 (Lopez-Morales+, 2016)J/ApJS/222/14 : Planetary candidates from 1st yr K2 mission (Vanderburg+, 2016)J/ApJS/224/2 : K2 EPIC stellar properties for 138600 targets (Huber+, 2016)J/ApJS/226/7 : Planet candidates discovered using K2's 1yr (Crossfield+, 2016)J/AJ/154/109 : California-Kepler Survey. III. Planet radii (Fulton+, 2017)J/MNRAS/472/1618 : Kepler study of starspot lifetimes (Giles+, 2017)J/AJ/155/21 : Planet candidates from K2 campaigns 5-8 (Petigura+, 2018)J/AJ/155/107 : HARPS-N obs. of K2-141 planetary system (Malavolta+, 2018)J/AJ/155/136 : Planets orbiting bright stars K2 campaigns 0-10 (Mayo+, 2018)J/AJ/156/277 : Sixty validated planets K2 campaigns 5-8 (Livingston+, 2018)J/ApJS/244/11 : Planet candidates and EBs in K2 campaigns 0-8 (Kruse+, 2019)J/AJ/159/211 : Exoplanet parameters from Kepler and K2 (Cloutier+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/163/41https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/163/41http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/163/41https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/163/41https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/163/41http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/163/41GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/163/41/table1K2-79 LC observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDObservation time, BJD-2400000dtime.epochdoublefluxRelative flux after removal of high-frequency systematic signalsphot.flux.densitydoubleffluxRelative flux of flattened light curve after removal of low-frequency signals (1)phot.flux.densitydoublee_ffluxUncertainties associated with fflux (1)stat.errordoubleJ/AJ/163/41/table2K2-222 LC observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDObservation time, BJD-2400000dtime.epochdoublefluxRelative flux after removal of high-frequency systematic signalsphot.flux.densitydoubleffluxRelative flux of flattened light curve after removal of low-frequency signals (1)phot.flux.densitydoublee_ffluxUncertainties associated with fflux (1)stat.errordoubleJ/AJ/163/41/table3K2-79 HARPS-N RV and stellar activity indicatorrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDObservation time, BJD-2400000dtime.epochdoubleRVelRadial velocitym/sphys.veloc;pos.heliocentricfloate_RVelRadial velocity errorm/sstat.error;spect.dopplerVelocfloatFWHMFull-width half-maximumkm/sspect.line.widthfloatconContrast%stat.fit.paramfloatBSBisector inverse spankm/sphys.velocdoublee_BSBisector inverse span errorkm/sstat.errordoubleSHKS-indexspect.indexdoublee_SHKUncertainty in SHKstat.errordoubleJ/AJ/163/41/table4K2-222 HARPS-N RV and stellar activity indicatorrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDObservation time, BJD-2400000dtime.epochdoubleRVelRadial velocitym/sphys.veloc;pos.heliocentricfloate_RVelRadial velocity errorm/sstat.error;spect.dopplerVelocfloatFWHMFull-width half-maximumkm/sspect.line.widthfloatconContrast%stat.fit.paramfloatBSBisector inverse spankm/sphys.velocdoublee_BSBisector inverse span errorkm/sstat.errordoubleSHKS-indexspect.indexdoublee_SHKUncertainty in SHKstat.errordouble