J/ApJ/806/228ivo://CDS.VizieR/J/ApJ/806/228doi:10.26093/cds/vizier.18060228CDSSoubiran F.Militzer B.2017-01-23T22:00:00Z2015-11-18T14:35:56ZCDS support team

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

cds-question@unistra.frastronomical-modelssolar-system-planetsWe present results from ab initio simulations of liquid water-hydrogen mixtures in the range from 2 to 70GPa and from 1000 to 6000K, covering conditions in the interiors of ice giant planets and parts of the outer envelope of gas giant planets. In addition to computing the pressure and the internal energy, we derive the Gibbs free energy by performing a thermodynamic integration. For all conditions under consideration, our simulations predict hydrogen and water to mix in all proportions. The thermodynamic behavior of the mixture can be well described with an ideal mixing approximation. We suggest that a substantial fraction of water and hydrogen in giant planets may occur in homogeneously mixed form rather than in separate layers. The extent of mixing depends on the planet's interior dynamics and its conditions of formation, in particular on how much hydrogen was present when icy planetesimals were delivered. Based on our results, we do not predict water-hydrogen mixtures to phase separate during any stage of the evolution of giant planets. We also show that the hydrogen content of an exoplanet is much higher if the mixed interior is assumed.2015ApJ...806..228Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/806/228CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJ/774/148 : Ab initio EOS for hydrogen-helium mixtures (Militzer+, 2013)J/ApJ/750/52 : Jupiter model with improved EOS (Nettelmann+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/806/228https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/806/228http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/806/228https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/806/228https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/806/228http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/806/228GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/ApJ/806/228/table1Equation of state of water-hydrogen mixturesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTemp[1000/6000] TemperatureKphys.temperatureintConc[0/1] Water concentrationphys.size;arith.ratiofloatDen[0.1/2.6] Mass densityg.cm**-3phys.densityfloatP[1.3/89.3] PressureGPaphys.pressurefloate_P[0.01/0.4] Uncertainty in PGPastat.errorfloatIntE[-13.92/-3.17] Internal energy (1)eVphys.energydoublee_IntE[0.0009/0.04] Uncertainty in IntE (1)eVstat.errorfloatGibbs[-22.44/-5.09] Gibbs free energy (1)eVphys.energydoublee_Gibbs[0.003/0.05] Uncertainty in Gibbs (1)eVstat.errorfloat