J/AJ/160/207ivo://CDS.VizieR/J/AJ/160/207doi:10.26093/cds/vizier.51600207CDSWilcomb+Wilcomb K.K.Konopacky Q.M.Barman T.S.Theissen C.A.,Ruffio J.-B.Brock L.Macintosh B.Marois C.2021-07-05T08:28:57Z2021-01-28T12:03:45ZCDS support team

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

cds-question@unistra.frbrown-dwarfsexoplanetsinfrared-astronomyspectroscopyWe present moderate-resolution (R~4000) K-band spectra of the "super- Jupiter," {kappa}-Andromedae-b. The data were taken with the OSIRIS integral field spectrograph at Keck Observatory. The spectra reveal resolved molecular lines from H2O and CO, and are compared to a custom PHOENIX atmosphere model grid appropriate for young planetary-mass objects. We fit the data using a Markov chain Monte Carlo forward-modeling method. Using a combination of our moderate-resolution spectrum and low-resolution, broadband data from the literature, we derive an effective temperature of Teff=1950-2150K, a surface gravity of logg=3.5--4.5, and a metallicity of [M/H]=-0.2--0.0. These values are consistent with previous estimates from atmospheric modeling and the currently favored young age of the system (<50Myr). We derive a C/O ratio of 0.70_-0.24_^+0.09^ for the source, broadly consistent with the solar C/O ratio. This, coupled with the slightly subsolar metallicity, implies a composition consistent with that of the host star, and is suggestive of formation by a rapid process. The subsolar metallicity of {kappa}-Andromedae-b is also consistent with predictions of formation via gravitational instability. Further constraints on formation of the companion will require measurement of the C/O ratio of {kappa}-Andromedae-A. We also measure the radial velocity of {kappa}-Andromedae-b for the first time, with a value of -1.4{+/-}0.9km/s relative to the host star. We find that the derived radial velocity is consistent with the estimated high eccentricity of {kappa}-Andromedae-b.2020AJ....160..207Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/207CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)J/A+A/463/671 : Rotational velocities of A-type stars. III. (Royer+, 2007)J/ApJ/723/684 : NIRSPEC ultracool dwarf radial velocity survey (Blake+,2010)J/A+A/525/A71 : Atmospheric parameters for 1273 stars (Wu+, 2011)J/ApJ/794/146 : M dwarfs with IR excess (Theissen+, 2014)J/MNRAS/440/1649 : ExoMol line lists for CH4 (Yurchenko+, 2014)J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)J/ApJ/804/146 : Atmospheric parameters for nearby B-F stars (David+, 2015)J/A+A/603/A30 : Evidence for 2 distinct giant planet pop. (Santos+, 2017)J/AJ/157/63 : Rad. relations for low-metallicity M-dwarf (Kesseli+, 2019)J/AJ/158/13 : The first 300 stars observed by the GPIES (Nielsen+, 2019)J/AJ/159/63 : New AO obs. of exoplanets & brown dwarf comp. (Bowler+,2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/160/207https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/160/207http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/160/207https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/160/207https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/160/207http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/160/207GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/AJ/160/207/fig2Fully reduced, combined, and flux calibrated moderate-resolution OSIRIS K-band spectra of {kappa} And brecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWave[1.9/2.4] Wavelengthumem.wldoubleFlux[1e-14/2.5e-14] Flux densityW.m**-2.um**-1phot.flux.density;em.IRdoublee_Flux[6.6e-16/6e-15] Uncertainty in FluxW.m**-2.um**-1stat.error;phot.fluxdouble