J/A+A/622/A153ivo://CDS.VizieR/J/A+A/622/A153doi:10.26093/cds/vizier.36220153CDSNagel E.Czesla S.Schmitt J.H.M.M.Dreizler S.Anglada-Escude G.,Rodriguez E.Ribas I.Reiners A.Quirrenbach A.Amado P.J.,Caballero J.A.Aceituno J.Bejar V.J.S.Cortes-Contreras M.,Gonzalez-Cuesta L.Guenther E.W.Henning T.Jeffers S.V.,Kaminski A.Kuerster M.Lafarga M.Lopez-Gonzalez M.J.Montes D.,Morales J.C. Passegger V.M.Rodriguez-Lopez C.Schweitzer A.,Zechmeister M.2019-02-25T14:17:56Z2019-02-13T06:16:16ZCDS support team

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

cds-question@unistra.frmultiple-starsexoplanetsradial-velocityWe report the detection of a Neptune-mass exoplanet around the M4.0 dwarf GJ 4276 (G 232-070) based on radial velocity (RV) observations obtained with the CARMENES spectrograph. The RV variations of GJ 4276 are best explained by the presence of a planetary companion with a minimum mass of m_b_sini~16M_{sun}_ on a P_b_=13.35-day orbit. The analysis of the activity indicators and spectral diagnostics exclude stellar induced RV perturbations and prove the planetary interpretation of the RV signal. We show that a circular single-planet solution can be excluded by means of a likelihood ratio test. Instead, we find that the RV variations can either be explained by an eccentric orbit or interpreted as a pair of planets on circular orbits near a period ratio of 2:1. Although the eccentric single-planet solution is slightly preferred, our statistical analysis indicates that none of these two scenarios can be rejected with high confidence using the RV time series obtained so far. Based on the eccentric interpretation, we find that GJ 4276 b is the most eccentric (e_b_=0.37) exoplanet around an M dwarf with such a short orbital period known today.2019A&A...622A.153Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/622/A153CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/622/A153https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/622/A153http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/622/A153https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/622/A153https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/622/A153http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/622/A153GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/622/A153/rvCARMENES radial-velocity time series for GJ 4276 (table C1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBarycentric Julian Datedtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricfloate_RVRadial velocity uncertaintym/sstat.errorfloatJ/A+A/622/A153/snoSierra Nevada Observatory V-band photometric time series of GJ 4276recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Date (HJD-2450000)dtime.epochdoubledVmagV-band magnitude normalized to zeromagphot.mag;em.opt.V;arith.ratiofloate_dVmagUncertainty in V-band magnitudemagstat.error;phot.magfloat