J/ApJ/818/106ivo://CDS.VizieR/J/ApJ/818/106doi:10.26093/cds/vizier.18180106CDSRodigas T.J.Arriagada P.Faherty J.Anglada-Escude G.Kaib N.,Butler R.P.Shectman S.Weinberger A.Males J.R.Morzinski K.M.,Close L.M.Hinz P.M.Crane J.D.Thompson I.Teske J.Diaz M.,Minniti D.Lopez-Morales M.Adams F.C.Boss A.P.2017-06-19T07:57:56Z2016-05-27T11:57:27ZCDS support team

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

cds-question@unistra.frradial-velocitymultiple-starsWe present high-contrast Magellan adaptive optics images of HD 7449, a Sun-like star with one planet and a long-term radial velocity (RV) trend. We unambiguously detect the source of the long-term trend from 0.6-2.15{mu}m at a separation of ~0.54". We use the object's colors and spectral energy distribution to show that it is most likely an M4-M5 dwarf (mass ~0.1-0.2M_{sun}_) at the same distance as the primary and is therefore likely bound. We also present new RVs measured with the Magellan/MIKE and Planet Finder Spectrograph (PFS) spectrometers and compile these with archival data from CORALIE and HARPS. We use a new Markov chain Monte Carlo procedure to constrain both the mass (>0.17M_{sun}_ at 99% confidence) and semimajor axis (~18 AU) of the M dwarf companion (HD 7449B). We also refine the parameters of the known massive planet (HD 7449Ab), finding that its minimum mass is 1.09_-0.19_^+0.52^M_J_, its semimajor axis is 2.33_-0.02_^+0.01^AU, and its eccentricity is 0.8_-0.06_^+0.08^. We use N-body simulations to constrain the eccentricity of HD 7449B to <~0.5. The M dwarf may be inducing Kozai oscillations on the planet, explaining its high eccentricity. If this is the case and its orbit was initially circular, the mass of the planet would need to be <~1.5M_J_. This demonstrates that strong constraints on known planets can be made using direct observations of otherwise undetectable long-period companions.2016ApJ...818..106Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/818/106CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/585/A5 : Exoplanet hosts/field stars age consistency (Bonfanti+, 2016)J/A+A/576/A69 : Li abundances in F stars (Delgado+, 2015)J/A+A/575/A18 : Revising the ages of planet-hosting stars (Bonfanti+, 2015)J/ApJ/799/163 : Chandra observations of solar analogs (Miller+, 2015)J/MNRAS/445/2223 : Mass estimation for FGK stars (Pinheiro+, 2014)J/MNRAS/443/L89 : Kapteyn's star spectrosc. measurements (Anglada-Escude+ 2014)J/AJ/147/86 : From binaries to multiples. I. FG-67 sample (Tokovinin, 2014)J/A+A/556/A150 : SWEETCat I. Stellar parameters for host stars (Santos+, 2013)J/A+A/555/A150 : Physical param. of cool solar-type stars (Tsantaki+, 2013)J/A+A/552/A119 : Planet-star and moon-planet interaction (Saur+, 2013)J/A+A/552/A64 : Gaia-RVS standards (Soubiran+, 2013)J/A+A/552/A6 : F-G MS stars abundances (Gonzalez Hernandez+, 2013)J/A+A/551/A112 : Metallicity-giant planet correlation (Mortier+, 2013)J/ApJ/766/9 : GALEX observations of exoplanet host stars (Shkolnik, 2013)J/ApJS/200/15 : HARPS-TERRA project. I. (Anglada-Escude+, 2012)J/ApJ/752/56 : BDKP III. Parallaxes for 70 ultracool dwarfs (Faherty+, 2012)J/A+A/545/A32 : Chemical abundances of 1111 FGK stars (Adibekyan+, 2012)J/AJ/142/176 : Exoplanet host stars. II. Interferometry (Mason+, 2011)J/A+A/535/A55 : 4 stars with long-period planets (Dumusque+, 2011)J/ApJ/709/168 : Eccentric orbits in exoplanets (Anglada-Escude+, 2010)J/ApJ/687/1264 : Age estimation for solar-type dwarfs (Mamajek+, 2008)J/A+A/487/373 : Spectroscopic param. of 451 HARPS-GTO stars (Sousa+, 2008)J/AJ/124/1144 : Orbits of single-lined spectroscopic binaries (Latham, 2002)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/818/106https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/818/106http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/818/106https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/818/106https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/818/106http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/818/106GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/ApJ/818/106/table1Radial velocities for HD 7449recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian Date of the observationdtime.epochdoubleRVel[-34/108] Radial velocitym/sphys.veloc;pos.heliocentricfloate_RVel[0.5/10] Uncertainty in RVelm/sstat.error;spect.dopplerVelocfloatInstInstrument code (1)meta.code;instrint