J/A+A/681/A55ivo://CDS.VizieR/J/A+A/681/A55doi:10.26093/cds/vizier/bc-n9/lffCDSHeidari N.Boisse I.Hara N.C.Wilson T.G.Kiefer F.Hebrard G.,Philipot F.Hoyer S.Stassun K.G.Henry G.W.Santos N.C.Acuna L.,Almasian D.Arnold L.Astudillo-Defru N.Attia O.Bonfils X.Bouchy F.,Bourrier V.Collet B.Cortes-Zuleta P.Carmona A.Delfosse X.Dalal S.,Deleuil M.Demangeon O.D.S.Diaz R.F.Dumusque X.Ehrenreich D.,Forveille T.Hobson M.J.Jenkins J.S.Jenkins J.M.Lagrange A.M.,Latham D.W.Larue P.Liu J.Moutou C.Mignon L.Osborn H.P.Pepe F.,Rapetti D.Rodrigues J.Santerne A.Segransan D.Shporer A.Sulis S.,Torres G.Udry S.Vakili F.Vanderburg A.Venot O.Vivien H.G.,Vines J.I.2026-07-03T06:35:51Z2024-01-11T12:26:43ZCDS support team

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

cds-question@unistra.frmultiple-starsexoplanetsradial-velocityTransiting planets with orbital periods longer than 40 d are extremely rare among the 5000+ planets discovered so far. The lack of discoveries of this population poses a challenge to research into planetary demographics, formation, and evolution. Here, we present the detection and characterization of HD 88986 b, a potentially transiting sub-Neptune, possessing the longest orbital period among known transiting small planets (<4R_{Earth}_) with a precise mass measurement ({sigma}M/M>25%). Additionally, we identified the presence of a massive companion in a wider orbit around HD 88986. To validate this discovery, we used a combination of more than 25 yr of extensive radial velocity (RV) measurements (441 SOPHIE data points, 31 ELODIE data points, and 34 HIRES data points), Gaia DR3 data, 21 yr of photometric observations with the automatic photoelectric telescope (APT), two sectors of TESS data, and a 7-day observation of CHEOPS. Our analysis reveals that HD 88986 b, based on two potential single transits on sector 21 and sector 48 which are both consistent with the predicted transit time from the RV model, is potentially transiting. The joint analysis of RV and photometric data show that HD 88986 b has a radius of 2.49+/-0.18R_{Earth}_, a mass of 17.2^-3.8^_+4.0^M_{Earth}_, and it orbits every 146.05^-0.40^_+0.43_d around a subgiant HD 88986 which is one of the closest and brightest exoplanet host stars (G2Vtype, R=1.543+/-0.065R_{sun}_, V=6.47+/-0.01mag, distance=33.37+/-0.04pc). The nature of the outer, massive companion is still to be confirmed; a joint analysis of RVs, HIPPARCOS, and Gaia astrometric data shows that with a 3{sigma} confidence interval, its semi-major axis is between 16.7 and 38.8au and its mass is between 68 and 284M_Jup_. HD 88986 b's wide orbit suggests the planet did not undergo significant mass loss due to extreme-ultraviolet radiation from its host star. Therefore, it probably maintained its primordial composition, allowing us to probe its formation scenario. Furthermore, the cold nature of HD 88986 b (460+/-8K), thanks to its long orbital period, will open up exciting opportunities for future studies of cold atmosphere composition characterization. Moreover, the existence of a massive companion alongside HD 88986 b makes this system an interesting case study for understanding planetary formation and evolution.2024A&A...681A..55Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/681/A55CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/505/853 : HD16760 radial velocity curve (Bouchy+, 2009)J/A+A/513/A69 : HD9446 radial velocity curve (Hebrard+, 2010)J/A+A/523/A88 : A Jupiter-mass companion around HD 109246 (Boisse+, 2010)J/A+A/538/A113 : RV of eight stars (Diaz+ 2012)J/A+A/545/A55 : RV of 5 stars (Boisse+, 2012)J/A+A/563/A22 : RV of 3 new hot Jupiters (Moutou+, 2014)J/A+A/585/A46 : RV of 5 stars (Bouchy+, 2016)J/A+A/588/A144 : RV of 15 targets (Wilson+, 2016)J/A+A/588/A145 : RV of 8 stars with giant planets (Hebrard+, 2016)J/A+A/601/A9 : HD17674, HD29021, and HD42012 radial velocities (Rey+, 2017)J/A+A/618/A103 : Gl617A and Gl96 radial velocity curves (Hobson+, 2018)J/A+A/625/A17 : SOPHIE data of Gliese 411 (Diaz+, 2019)J/A+A/636/L6 : HD 158259 SOPHIE radial velocities (Hara+, 2020)J/A+A/651/A11 : SOPHIE radial velocities of 27 F/G stars (Dalal+, 2021)J/A+A/653/A78 : Radial velocity and activity indicators (Demangeon+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/681/A55https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/681/A55http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/681/A55https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/681/A55https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/681/A55http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/681/A55GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/681/A55/elodieHD88986 ELODIE observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDReduced Julian date (JD-2400000)dtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricdoublee_RVRadial velocity errorm/sstat.errordoubleFWHMFull width at half maximumm/sspect.line.widthdoublee_FWHMFull width at half maximum errorm/sstat.error;phys.angSizedoubleContContrastphot.flux;arith.ratiodoublee_ContContrast errorstat.errordoubleJ/A+A/681/A55/sophiedHD88986 SOPHIE DRS 3-1 observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDReduced Julian date (JD-2400000)dtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricdoublee_RVRadial velocity errorm/sstat.errordoubleFWHMFull width at half maximumm/sspect.line.widthdoublee_FWHMFull width at half maximum errorm/sstat.error;phys.angSizedoubleBISBisector spanm/sphys.velocdoublee_BISBisector span errorm/sstat.errordoubleRHKR_HK_ activity indexphot.flux;arith.ratiodoublee_RHKR_HK_ activity index errorstat.errordoubleJ/A+A/681/A55/sophiepHD88986 SOPHIE+ observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDReduced Julian date (JD-2400000)dtime.epochdoubleRVRadial velocitykm/sphys.veloc;pos.heliocentricfloate_RVRadial velocity errorkm/sstat.errorfloatBISBisector spankm/sphys.velocfloatSMW? Mont-Wilson S indexphot.flux;arith.ratiodoublenullablee_SMW? Mont-Wilson S index errorstat.errordoublenullableNa? Na indexspect.indexdoublenullablee_Na? Na index errorstat.errorfloatnullableJ/A+A/681/A55/hires1HD88986 HIRES before CCD change observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDReduced Julian date (JD-2400000)dtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricfloate_RVRadial velocity errorm/sstat.errorfloatSMWMont-Wilson S indexphot.flux;arith.ratiofloatHa? H{alpha} indexspect.indexfloatnullableCorVRadial velocity correction valuem/sphys.veloc;arith.difffloate_CorV1{sigma} uncertainty in CorVm/sstat.errorfloatJ/A+A/681/A55/hires2HD88986 HIRES after CCD change observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDReduced Julian date (JD-2400000)dtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricfloate_RVRadial velocity errorm/sstat.errorfloatSMWMont-Wilson S indexphot.flux;arith.ratiofloatHa? H{alpha} indexspect.indexfloatnullableCorVRadial velocity correction valuem/sphys.veloc;arith.difffloate_CorV1{sigma} uncertainty in CorVm/sstat.errorfloat