J/A+A/703/A201ivo://CDS.VizieR/J/A+A/703/A201CDSMurgas F.Palle E.Suarez Mascareno A.Korth J.Pozuelos F.J.,Hobson M.J.Lavie B.Lovis C.Sousa S.G.Bossini D.Parviainen H.,Castro-Gonzalez A.Adibekyan V.Allende Prieto C.Alibert Y.Bouchy F.,Briceno C.Caldwell D.A.Ciardi D.Clark C.Collins K.A.Collins K.I.,Cristiani S.Dumusque X.Ehrenreich D.Figueira P.Furlan E.,Genova Santos R.Gnilka C.Gonzalez Hernandez J.I.Hartman Z.,Howell S.B.Jenkins J.M.Law N.Littlefield C.Lo Curto G.Mann A.W.,Martins C.J.A.P.Mehner A.Micela G.Molaro P.Nunes N.J.Pepe F.,Rebolo R.Relles H.M.Santos N.C.Scott N.J.Seager S.Sozzetti A.,Udry S.Watkins C.N.Winn J.N.Zapatero Osorio M.R.Ziegler C.2026-03-02T06:25:50Z2025-11-20T08:42:45ZCDS support team

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

cds-question@unistra.frmultiple-starsexoplanetsspectroscopyradial-velocityvisible-astronomySuper-Earths and mini-Neptunes are missing from our Solar System, yet they appear to be the most abundant planetary types in our Galaxy. A detailed characterization of key planets within this population is important for understanding the formation mechanisms of rocky and gas giant planets and the diversity of planetary interior structures. In 2019, NASA's TESS satellite found a transiting planet candidate in a 17.6-day orbit around the star TOI-283. We started radial velocity (RV) follow-up observations with ESPRESSO to obtain a mass measurement. Mass and radius are measurements critical for planetary classification and internal composition modeling. We used ESPRESSO spectra to derive the stellar parameters of the planet candidate host star TOI-283. We then performed a joint analysis of the photometric and RV data of this star, using Gaussian processes to model the systematic noise present in both datasets. We find that the host is a bright K-type star (d=82.4pc, Teff=5213+/-70K, V=10.4mag) with a mass and radius of M*=0.80+/-0.01M_{sun}_ and R*=0.85+/-0.03R_{sun}_. The planet has an orbital period of P=17.617-days, a size of Rp=2.34+/-0.09R_{Earth}_, and a mass of Mp=6.54+/-2.04M_{Earth}_. With an equilibrium temperature of ~600 K and a bulk density of {rho}_p_=2.81+/-0.93g/cm^3^, this planet is positioned in the mass-radius diagram where planetary models predict H_2_O- and H/He-rich envelopes. The ESPRESSO RV data also reveal a long-term trend that is probably related to the star's activity cycle. Further RV observations are required to confirm whether this signal originates from stellar activity or another planetary body in the system.2025A&A...703A.201Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/703/A201CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/703/A201https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/703/A201http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/703/A201https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/703/A201https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/703/A201http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/703/A201GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/A+A/703/A201/tablec1ESPRESSO radial velocity measurements and stellar activity indicatorsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBarycentric julian date (TDB)dtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricdoublee_RVRadial velocity errorm/sstat.errorfloatFWHMFull-width at half maximum of the CCFm/sspect.line.widthfloate_FWHMFull-width at half maximum errorm/sstat.error;phys.angSizefloatBISBisector inverse slope of the CCFm/sphys.velocfloate_BISBisector inverse slope of the CCF errorm/sstat.errorfloatContContrast of the CCFphot.flux;arith.ratiofloate_ContContrast of the CCF errorstat.errorfloatSindexS-indexspect.indexfloate_SindexS-index errorstat.errorfloatNaSodium activity indexspect.indexfloate_NaSodium activity index errorstat.errorfloatHalphaHalpha activity indexspect.indexfloate_HalphaHalpha activity index errorstat.error;spect.linefloatCaCalcium activity indexspect.indexfloate_CaCalcium activity index errorstat.errorfloat